United States 

Department of 

Agriculture 

Forest Service 

Pacific Southwest 

Research Station 

General Technical 

Report PSW-GTR-146 

Screening Douglas-fir for Rapid 

Early Growth in Common-Garden 

Tests in Spain 

Gabriel Toval Hernandez 

Guillermo Vega Alonso 

Gonzalo Puerto Arribas 

James L. Jenkinson 
Toval Hernandez, Gabriel; Vega Alonso, Guillermo; Puerto Arribas, Gonzalo; Jenkinson, James L. 

1993. Screening Douglas-fir for rapid early growth in common-garden tests in Spain. Gen. 

Tech. Rep. PSW-GTR-146. Albany, CA: Pacific Southwest Research Station, Forest Service, U.S. 

Department of Agriculture; 43 p. 

Abstract: Douglas-firs from 91 seed sources in North America were evaluated after 5 and 6 years in 

15 common-garden tests in the mountainous regions of northwest and north central Spain. Analyses 

of tallest trees showed that most of the sources of highest potential for reforestation in Spain are found 

in regions where the Pacific Ocean air mass dominates climate. Fast growers came from coastal 

slopes of the Coast Ranges from northwest California to the Georgia Strait of southwest British 

Columbia and inland slopes of the Olympic Mountains and Coast and Cascade Ranges facing the 

Puget Trough in western Washington and Willamette Valley in northwest Oregon. Slow growers 

came from latitudes south of 44° and north of 50° N, high altitudes west of the crest of the Cascade 

Ranges, and regions east of the crest where the continental air mass dominates climate. 

Retrieval terms: climatic adaptation, genetic variation, genotype-environment interaction, species 

introduction, tree growth, Pseudotsuga menziesii, P. flahaulti, P. macrolepis 

The Authors:

Gabriel Toval Hernandez is Director Investigacion Forestal, Empresa Nacional de Celulosas, 

Apartado de Correos n° 50, 36080 Pontevedra, España, and was formerly Director, Centro de 

Investigaciones Forestales de Lourizán, Consellería de Agricultura, Gandería e Montes, Xunta de 

Galicia, Pontevedra, España. Guillermo Vega Alonso and Gonzalo Puerto Arribas are Ingenieros de 

Montes, Centro de Investigaciones Forestales de Lourizán, Consellería de Agricultura, Gandería e 

Montes, Xunta de Galicia, Apartado de Correos n° 27, 36080 Pontevedra, España. James L. 

Jenkinson is Plant Physiologist, Pacific Southwest Research Station, USDA Forest Service, Albany, 

California. 

Acknowledgments:

Gerald D. Barnes, President, Tree Improvement Enterprises, Inc., Cottage Grove, Oregon; Jay 

Kitzmiller, Regional Geneticist, Pacific Southwest Region, Genetic Resources Center, Chico, California; 

and Nicholas T. Vagle, Tree Improvement−Reforestation Forester, Siskiyou National Forest, Grants 

Pass, Oregon, reviewed the manuscript. Sylvia R. Mori, Mathematical Statistician, Pacific Southwest 

Research Station, Albany, California, provided statistical reviews. May E. Huddleston, Publications 

Consultant, Petaluma, California, and Sandy Young, Technical Editor, Pacific Southwest Research 

Station, Albany, provided editorial reviews. Diana Doyal, Computer Programmer Analyst, Pacific 

Southwest Research Station, Albany, supplied the statistical analyses and computer graphics. 

Publisher:

Pacific Southwest Research Station 

(Mailing address: P.O. Box 245, Berkeley, CA 94701-0245

Telephone: 510-559-6300) 

August 1993 
Screening Douglas-fir for Rapid 

Early Growth in Common-Garden 

Tests in Spain 

Gabriel Toval Hernandez 

Guillermo Vega Alonso 

Gonzalo Puerto Arribas 

James L. Jenkinson 

Contents

In Brief ......................................................................................................................ii 

Introduction ............................................................................................................1 

Reforestation by Species Introduction ............................................................ 1

Performance of Pacific Coast Conifers ...............................................................2

Methods and Materials ............................................................................................2

Seed Sources ........................................................................................................2

Nursery Procedures .............................................................................................3

Planting Sites .......................................................................................................3

Plantation Procedures .........................................................................................3

Analyses of Tree Heights ...................................................................................11

Results ....................................................................................................................17

Seed Source Effects on Tree Height ..................................................................17

Planting Site Effects on Tree Height ..................................................................17

Seed Sources Ranked by Tall Trees ...................................................................17 

Seed Source-Planting Site Interaction ..............................................................17 

Seed Source Grades and Climate Zones ..........................................................24

Discussion ..............................................................................................................28 

Best Seed Sources Defined ................................................................................28 

Seed Source Climates Typed ............................................................................28 

European Findings Compared ..........................................................................29 

Implications for Reforestation in Spain ...............................................................32 

References .............................................................................................................33 

Appendix Tables ...................................................................................................34 

Cover: Douglas-fir in the eighth growing season in the Gamalleira common-garden test, 

in the Rio Eo watershed in Lugo Province, Galicia, northwest Spain (August 1987). 
In Brief... 

Toval Hernandez, Gabriel; Vega Alonso, Guillermo; 

Puerto Arribas, Gonzalo; Jenkinson, James L. 1993. 

Screening Douglas-fir for rapid early growth in 

common-garden tests in Spain. Gen. Tech. Rep. 

PSW-GTR-146. Albany, CA: Pacific Southwest 

Research Station, Forest Service, U.S. Department of 

Agriculture; 43 p. 

Retrieval terms: climatic adaptation, genetic variation, 

genotype−environment interaction, species introduction, 

tree growth, Pseudotsuga menziesii, P. flahaulti, P. 

macrolepis 

To locate superior Douglas-fir for reforestation in Spain, 

heights of Douglas-firs from 91 seed sources in North 

America were assessed 5 and 6 years after planting in 15 

common-garden tests in the mountainous regions of 

northwest and north central Spain. The sources embody 

Douglas-fir forests in coastal and inland regions of southern 

British Columbia, Washington, Oregon, and northern 

California and natural stands of two related species in 

eastern Mexico. Plantations were installed on cleared 

planting sites from near the border with northern Portugal 

to near the border with southern France. Ten plantations 

were situated in coastal and inland regions of the Macizo 

Galaico Duriense of Galicia, in the Provinces of 

Pontevedra, Orense, and Lugo, and six plantations, in 

coastal and inland regions of the Cordillera Cantabrica, 

Montes Vascos, and Pirineos (Pyrenees), in the Provinces 

of Asturias, León, Guipuzcoa, and Navarra. 

The test design consisted of three randomized complete 

blocks of seed source plots, except nine blocks in one 

Asturias plantation. The principal plantations received 

86 and 87 sources and were situated in western and 

eastern Orense Province, in regions of contrasting coastal 

and interior climates in northwest Spain. Each had 25 

seedlings per source plot and covered 6 hectares. The 

satellite plantations received from 4 to 31 sources and 

were arrayed from Portugal to France. Each had 81 

seedlings per source plot, except 64 or 49 per plot for a 

few sources in the León plantation, and 5 per plot in the 

Asturias plantation with nine blocks. The plantation 

nearest Portugal received 22 sources, was situated in the 

Rio Limia watershed of southern Orense Province, and 

covered 4.8 hectares. That nearest France received 31 

sources, was situated in the Pirineos of northern Navarra, 

and covered 6.8 hectares. Seedlings were spaced 3 m 

apart in every plantation. 

Tree height was measured 5 years after planting, 

except 6 years in the plantations in Asturias and León. 

Seed source and planting site effects were assessed by 

analysis of variance. Analyses were run using first the 

mean of al I trees in each source plot and then the means 

of those trees most likely to dominate developing stands−

the 15, 10, and 5 tallest in each plot, except 2 and 1 

tallest in the Asturias plantation with nine blocks. In the 

principal plantations, 5 trees per plot represented 20 

percent of those planted, and in the satellite plantations, 

15 per plot represented 18.5 percent, except the Asturias 

plantation where 1 per plot represented 20 percent. 

Source rankings in any particular plantation were 

practically the same for source means based on tallest 

trees as for those based on all trees. 

Plantation height ranged from 0.4 m on harsh sites up 

to 2.3 m on the better sites, based on the means of all 

trees in each plot. Based on means of the dominant 

trees, the 5 and 15 tallest in each plot in the principal 

and satellite plantations, respectively, height ranged from 

0.6 m on the interior site in eastern Orense Province to 

2.5 m on a coastal site in Asturias. The dominants 

averaged more than 1.4 m tall in eight plantations, 

including one in Lugo, the two in Asturias, the one in 

León, the two in Guipuzcoa, and the anchor plantations 

in southern Orense and northern Navarra. 

Seed source effects were pronounced and highly 

significant (p <0.01) in 12 plantations. Browsing livestock 

and wildfire masked the source effects in one plantation 

in Lugo, and soil drainage problems masked those in 

one in Guipuzcoa. In most plantations, trees of the best 

sources averaged up to three times taller than those of 

the poorest sources. To identify the best sources, every 

source was graded by the percentage of tests in which 

the mean of its tallest trees (18 to 20 percent of those 

planted) exceeded plantation height, using only those 

plantations where source effects were significant. Trees 

of 44 of the 91 sources that were graded showed good to 

superior growth potentials, exceeding plantation height 

in half or more of the tests in which the sources were 

assessed. Interactions of seed source and planting site 

were significant (p <0.05 or <0.01) in nine of the pairings 

of plantations that had from 5 to 85 sources in common. 

In each pairing, there were sources that grew well on 

both sites, others that grew poorly, and still others that 

grew well on one site and poorly on the other. 

Seed origins of the 44 best sources, those that show 

highest promise for reforestation in Spain, are concentrated 

at low to middle altitudes in Pacific Slope forests where 

the Pacific Ocean air mass dominates climate. Forests 

of major interest are situated in coastal and inland 

regions, including maritime slopes of the North Coast 

Range of northwest California, the Oregon and 

ii 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
Washington Coast Ranges, the Olympic Peninsula, and 

the Georgia Strait of southwest British Columbia, and 

inland slopes of the Olympic Mountains and Coast and 

Cascade Ranges facing the Puget Trough in western 

Washington and Willamette Valley in northwest Oregon. 

Most of the fast growers came from stands at latitudes of 

44° to 50° N and altitudes of 60 to 730 m (1005 m) 

above sea level. Most of the slow growers came from 

south of 44° and north of 50° N, high altitudes west of 

the crest of the Cascade Ranges, regions east of the 

Cascade crest where the continental air mass dominates 

climate, and eastern Mexico. 

Early growth performances of Douglas-fir in commongarden tests in Spain warn that plantation success critically 

depends on seed source. To delimit forest regions in 

North America in which to collect Douglas-fir for future 

tree planting programs in Spain, we located origins of 

the fast and slow growers on maps showing established 

tree seed zones and plant climate zones. The resulting 

distributions show that most of the fast growers are 

found in Pacific climate types, in 27 contiguous seed 

zones in southwest British Columbia (4 zones), western 

Washington (13 zones), and northwest Oregon (10 zones). 

The remaining fast growers suggest three separate groups 

in a total of seven seed zones in coastal and inland 

regions of extreme southwest Oregon and northwestern 

California. 

iii 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
Figure 1−Major mountain ranges and river systems in 

northern Spain. 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993
Introduction 

Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco), 

the dominant timber tree in the coniferous forests 

of Pacific North America, is of major interest to 

foresters on the Iberian Peninsula. Introduced in the 

mountainous coastal and inland regions of northern 

Spain and Portugal, it grows rapidly in mixed or pure 

stands, consistently outperforms indigenous and 

introduced trees, and is a prime choice for reforestation. 

Unfortunately, reproductively mature stands are too small 

and too few to provide the genetic base and quantity of 

seeds needed for extensive planting programs. And like 

early introductions of most species, seed origins in the 

native range are unknown. 

To identify and select best seed sources for reforestation, 

long-term common-garden tests of Douglas-fir from British 

Columbia to California and Mexico were installed on 

diverse forest sites in northwest and north central Spain. 

A definitive evaluation requires trees near midrotation 

age, but reforestation cannot be halted simply to await 

test results. Experience in western Oregon and northern 

California suggests that useful evaluations are possible 

when trees are 5 to 10 years old. On typical planting 

sites there, rapid early growth characterizes seed sources 

of high potential, even if it cannot predict those which 

ultimately prove best. To ensure successful reforestation 

in Spain, the planting stock used should be produced 

using known seed sources screened for rapid early growth 

in typical planting environments. 

In this paper, we evaluate seed source effects on tree 

height after 5 and 6 years in the field, assess seed 

source−planting site interaction, and grade 91 different 

sources for growth performance. We describe geographic 

distributions of fast and slow growers with respect to 

tree seed zones and plant climate zones of origin and 

suggest the seed zones and altitudes from which to 

collect Douglas-fir seeds for reforestation programs in 

Spain. Our findings apply directly to the mountainous 

regions of northwest and north central Spain and may 

be safely extrapolated to those in adjoining northern 

Portugal and northeast, west central, and southern Spain. 

Reforestation by Species 

Introduction 

Spain is the second largest country in western Europe, 

after France, and excepting Switzerland, is the most 

mountainous. As in other European and Mediterranean 

countries, 20 centuries of woodcutting, livestock grazing, 

and farming of cleared timberlands and woodlands have 

destroyed much of Spain's original hardwood and 

coniferous forests. Frequent fires and cultivation have 

caused massive soil erosion on steep slopes and left a 

legacy of stony, degraded landscapes over vast regions. 

Residual forests are restricted in extent and, in large part, 

are genetically impoverished. 

Professional foresters and concerned forest landowners 

have worked for decades to stabilize watersheds and 

develop anew the resources needed for wood products 

industries. To supply the volumes of wood and pulp 

that the remnant forests could not, extensive plantings of 

both native and introduced tree species were begun in 

the 1940's (Pardos and Gil 1986). The resulting 

plantations extended from the Atlantic Ocean to the 

Mediterranean Sea and blanketed large areas in the 

mountains of northern Spain. Plantations were established 

in coastal and inland regions of the Macizo Galaico 

Duriense in northwest Spain (Instituto Geografico 

Nacional 1982), along the Cordillera Cantabrica and 

Montes Vascos in north central Spain, and through the 

Pirineos (Pyrenees) to the Sierra de Montseny of Cataluña 

in northeast Spain (fig. 1). 

Slow growth characterizes some extensive plantings 

in every region, and numerous species have been tried 

in a continuing search for suitably adapted and 

undemanding, fast growers. Prominent native pines that 

have been widely planted are Italian stone pine, Austrian 

pine, maritime pine, Aleppo pine, and Scotch pine 

(Pinus pinea, P. nigra, P. pinaster, P. halepensis, and P. 

sylvestris, respectively). 

Non-native trees were first introduced at the turn of 

the century, and many have survived and grown well. 

Successful conifers include the Corsican variety of Austrian 

pine (Pinus nigra var. corsicana), European and Japanese 

larches (Larix decidua, L. leptolepis), Norway spruce 

(Picea abies), Atlas cedar (Cedrus atlanticus) from North 

Africa, and Douglas-fir (Pseudotsuga menziesii var. 

menziesii), Port-Orford-cedar (Chamaecyparis 

lawsoniana), coast redwood (Sequoia sempervirens), 

and Monterey pine (Pinus radiata) from the Pacific United 

States. Successful hardwoods include several eucalypts 

from Australia (Eucalyptus globulus, E. camaldulensis, 

and others), poplars from a host of countries (Populus 

spp.), and northern red oak and pin oak (Quercus rubra, 

Q. palustris) from the Eastern United States. 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
The most spectacular introductions are Monterey pine 

(Pinus radiata) in Pais Vasco and blue gum (Eucalyptus 

globulus) in Galicia. First brought as curiosities by 

travelers, these dissimilar species now thrive in maritime 

regions on the Atlantic Coast and exemplify the use of 

introduced trees to create highly productive forests on 

depleted, eroded soils. 

Performance of Pacific Coast 

Conifers 

Pacific North American conifers grow well in Spain. 

Douglas-fir stands that were planted 30 to 70 years ago 

in Cantabria, Pais Vasco, and Cataluña have grown as 

well as those in the Oregon Coast Range, where volume 

growth ranges up to 21 m3/ha/yr (Williamson and 

Twombly 1983). Like Monterey pine, both coast redwood 

and Port-Orford-cedar also thrive in Spain's Atlantic 

Coast regions. Coast redwoods in a stand planted near 

Comillas, Cantabria, ranged up to 35 m in height after 

42 years, and volume growth averaged 25 m3/ha/yr 

(Toval and others 1982a). Dominants in Port-Orfordcedar stands planted in La Coruña Province, Galicia, 

and Guipuzcoa Province, Pais Vasco, averaged 12.3 

and 10.7 m in height after 20 and 16 years, and volume 

growth averaged 17.2 and 13.7 m3/ha/yr (Fernandez 

and Michel 1982). Grand fir (Abies grandis) has grown 

the fastest in a comprehensive array of North American, 

European, and Mediterranean conifers planted in the 

Sierra de Montseny, near the Mediterranean Coast of 

Gerona Province, Cataluña (pers. commun., Emilio 

Garolera, Consorci Forestal de Catalunya, April 1987). 

Douglas-fir grows well in coastal and inland regions 

and is a golden option for widespread reforestation. It 

outgrows European larch, Austrian pine, Norway spruce, 

and Atlas cedar in intermingled stands in Pais Vasco and 

Cataluña, and dominates Scotch pine in mixed plantations 

in the Sierra de Montseny north of Barcelona and in the 

eastern Sierra de Guadarrama north of Madrid. It 

regenerates in and overtops developing stands of native 

oaks in northwest and northeast Spain, in Pontevedra 

Province in Galicia and Gerona Province in Cataluña. 

Its superior tolerance of low temperature is evident in 

inland and upland areas where hard winter freezes have 

repeatedly damaged or killed Monterey pine and blue 

gum. Vigorous individuals and small stands are widely 

scattered in Galicia, and their presence suggests that 

Douglas-fir might grow well even on the rocky, granitic 

soils above 800 m of altitude, where scrub now covers 

300,000 hectares. Scotch pine was planted on these 

harsher upland sites, but strong winds and heavy snows 

have shattered the surviving stands. 

Methods and Materials 

Common-garden tests were established in northwest 

and north central Spain to evaluate Douglas-fir from a 

total of 91 localities in southern British Columbia, 

Washington, Oregon, northern California (Pseudotsuga 

menziesii), and eastern Mexico (P. flahaulti, P. macrolepis). 

The tests were installed under the direction of Dr. 

Fernando Molina Rodríguez, Director of the Lourizán 

Forest Research Center, Pontevedra, Galicia, from 1953 

to 1986 and Gabriel Toval Hernandez, Chief of the 

Center's Species Introduction Program. 

Seeds of 87 sources from British Columbia to Mexico 

were obtained from the 1966-68 collections made by 

the International Union of Forestry Research Organizations 

(IUFRO). Seeds of four sources in central California 

came from 1970 collections made by the Pacific 

Southwest Research Station's Institute of Forest Genetics 

(IFG), Placerville, California (table 1). 

Seedlings were planted in climatic and edaphic 

environments typical of the mountainous regions of 

northern Spain. The two principal plantations of IUFRO 

sources, La Hermida and Sierra del Eje, were installed in 

contrasting climates in 1978 (table 2). Growth and 

survival through 5 years in these tests have been reported 

(Toval 1985). Subsets of the IUFRO and IFG sources 

were distributed in 14 satellite plantations installed in 

1978 to 1981. For this report, 20 sources were assessed 

in six or more plantations; 18 others, in five; another 20, 

in four; 22 more, in three; and 11, in two (Appendix 

table 1). Sources from northern regions were represented 

more often than those from southern regions. The 

British Columbia and Washington sources averaged 5.00 

and 5.03 repeats, respectively, and the Oregon and 

California sources, 4.13 and 3.85 repeats. 

Seed Sources 

Douglas-fir (Pseudotsuga menziesii) was sampled over 

14° of latitude and 9° of longitude, and at altitudes of 45 

to 1600 m above sea level (figs. 2-3, table 1). The 

sources represent natural stands in mixed conifer forests 

ranging from latitude 38.7° N in central California to 

52.7° N in southern British Columbia and extend through 

maritime and inland regions of the Pacific Slope to 

continental regions east of the crest of the Cascade 

Ranges in Washington and Oregon. Coastal sources 

reach longitude 126.1 ° W on Vancouver Island, 124.4° 

W in Washington, 124.2° W in Oregon, and 124.0° W 

in California, and inland sources, 119.2° W in British 

Columbia, 117.2° W in Washington, 121.4° W in Oregon, 

and 120.5° W in California. 

2 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
Sources were chosen in 9 areas in southern British 

Columbia, including 4 on Vancouver Island and 5 on 

the mainland; 31 areas in Washington, 24 on the Pacific 

Slope and 7 east of the crest of the Cascade Ranges; 23 

areas in Oregon, 22 on the Pacific Slope and 1 east of 

the crest; and 26 areas in California, 23 in the North 

Coast Range and Klamath Mountains and 3 in the Cascade 

Range−Sierra Nevada. Sources west of the crest of the 

Cascade Ranges−Sierra Nevada represent the green race 

(var. menziesii), and those east of the crest, the blue race 

(var. glauca). Single sources of related species (P. flahaulti, 

P. macrolepis) were collected in the Sierra Madre Oriental, 

eastern Mexico. 

The Pacific Slope sources represent 64 tree seed zones, 

6 in British Columbia (Lines 1987), 21 in Washington, 

20 in Oregon, and 17 in California (Buck and others 

1970, USDA Forest Service 1969, 1973). Source altitudes 

ranged from 45 to 730 m above sea level in British 

Columbia, 60 to 760 m in Washington, 75 to 1600 m in 

Oregon, and 60 to 1555 m in California. 

Mature cones were picked from 15 trees per locality, 

except where noted differently (table 1). Dominant 

trees were located roughly 100 m apart in stands ranging 

up to 1.6 km across (Barner 1971). Cones were sundried, and seeds were extracted, cleaned, air-dried, 

mixed to form one bulk seedlot per source, and stored in 

freezers at -9° C. 

Nursery Procedures 

Seedlings were produced in the Lourizán Forest 

Research Center nursery. The nursery is situated on Ria 

de Pontevedra on the south coast of Galicia, at latitude 

42.4° N and about 10 m above sea level (fig. 4). Here, 

growing seasons are long, winters are mild, and the 

Atlantic Ocean air mass dominates the climate as the 

Pacific Ocean air mass dominates climate in the coastal 

regions of Oregon and northwest California. 

Seeds were chilled 30 days in wet sand at 4° C and 

germinated outdoors in the period from May to July. 

The chilled seeds were sown in flats filled with a standard 

mix of peat, sand, and granitic soil (1:1:1) that had been 

fumigated with vapam to control soilborne pathogens. 

In their first winter, seedlings were transplanted 

individually into black polyethylene bags measuring 8 

cm in diameter and 20 cm deep. The planting medium 

was a finely ground pine bark that had been amended 

with a balanced mineral fertilizer (N, P, K, Mg, Mn, B, 

Cu, and Mo). During transplanting, the medium in each 

container was inoculated with a handful of mycorrhizal 

soil dug from the conifer arboretum at Lourizán (Toval 

1983). 

Seedlings were planted in common-garden tests after 

one summer in the containers. Plantations were installed 

on cleared sites from May 1978 to April 1981. Planting 

was done in autumn, winter, or spring, depending on 

site location and weather conditions (table 2). 

Planting Sites 

The planting site climates and soils are typical of 

those found in the mountainous regions of northern 

Spain (Montero de Burgos and González 1974, Toval 

and others 1982b). The planting sites range from latitude 

42° to 43.5° N, the same as southernmost Oregon (fig. 

4, table 2). They extend eastward from longitude 8.3° 

W in the Macizo Galaico Duriense of southwest Galicia 

to 1° W in the Pirineos of northeast Navarra, and vary 

from 450 to 1360 m above sea level. Ten sites are 

located in coastal and inland regions of Galicia, northwest 

Spain: six in Lugo Province, three in Orense Province, 

and one in Pontevedra Province. Six others are distributed 

across north central Spain: two on coastal slopes of the 

Cordillera Cantabrica in Asturias, one inland in the 

mountains of northern León, two inland in the Montes 

Vascos of Guipuzcoa, and one inland in the Pirineos of 

Navarra. A detailed topographic map of these regions is 

available (Instituto Geografico Nacional 1982). 

Planting sites were prepared by proven methods for 

the region, slope, soil type, and vegetative cover (ICONA 

1975). Sites on gentle slopes, like those at Sierra del Eje 

and Regavel la, were tractor-plowed to a depth of 60 cm. 

Sites on steep slopes, like those at La Hermida, Bande, 

Valdemadeiro, Gamalleira, and La Vecilla, were tractorbladed along the contour to form planting terraces. To 

control aggressive sprouters, improve soil drainage, and 

facilitate planting, as at La Vecilla, terraces were ripped 

to a depth of 60 cm using chisels set 50 cm apart. 

Plantation Procedures 

The principal plantations, La Hermida and Sierra del 

Eje, were situated just inside the northwest and northeast 

boundaries of Orense Province (fig. 4, table 2). Here, 

seedlings of 86 and 87 IUFRO seed sources were planted 

on sites of contrasting climate, one inland with a short 

growing season and cold winter and the other coastal 

with a longer growing season and milder winter (Toval 

and others 1982b). The plantation design consisted of 

three randomized complete blocks of seed source plots. 

Each plot contained 25 seedlings set 3 m apart in a 5 by 

5 grid and was made large enough to carry a group of 

five or six trees to rotation age. 

The 14 satellite plantations were arrayed from Bande 

in southwest Orense Province to Ochagavía in northeast 

Navarra. The Bande plantation was situated in the Rio 

Limia watershed, in sight of northwest Portugal. The 

Ochagavía plantation was situated near midslope in the 

Pirineos, very near the border with southwest France. 

Unlike the principal plantations, which were allocated 

the full set of IUFRO sources, the satellite plantations 

were allocated subsets of the IUFRO and IFG sources 

(table 1, Appendix table 1). Which sources and how 

many were allocated depended on the planting site, 

seedlings available, and resources of cooperators. 

3 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
Figure 2

−Douglas-fir seed sources in North America 

assessed for tree growth in common-garden tests in Spain. 

The key shows the source code number and locality of 

seed origin. The diamond symbol (♦) marks a source for 

which mean tree height exceeded plantation height in half 

or more of the tests in which the source was assessed. 

See fig. 3 

for the tree seed zones and altitudes of seed 

origin, and table 1 for the Mex

ico sources. 

4 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
5 

USDA Forest Service Gen. Tech. Rep. PSWGTR-146. 1993 
Figu

re 3−Douglas-fir seed sources in North America 

assessed for tree growth in common-garden tests in Spain. 

The key shows the tree seed zone, source code number, 

and altitude of seed origin. The diamond symbol (♦) marks 

a source for which mean tree height exceeded plantation 

height in half or more of the tests in which the source was 

assessed. See fig. 2 for the localities of seed origin, and 

table 1 for the Mexico sources. 

6 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
7 

USDA Forest Service Gen. Tech. Rep. PSWGTR-146. 1993 
Table 1−Douglas-fir seed sources graded for tree growth in common-garden tests in Spain 

North America Tree Plant Seed source location Seed 

Seed source1, trees, and seed climate source Tests 

Locality zone2 zone3 Altitude Lat Long grade4 used5 

British Columbia 

3 15 Alexandria 

14 ―- Eagle Bay 

24 15 

31 15 

♦32 15 

♦34 15 

♦39 15 

40 15 

♦45 15 

Washington 

48 16 

50 15 

♦51 16 

♦53 15 

♦54 15 

58 15 

59 16 

♦60 16 

61 15 

♦62 15 

♦63 15 

♦64 15 

65 15 

68 16 

♦72 16 

♦73 17 

♦75 15 

♦76 16 

♦77 15 

78 15 

♦80 15 

82 15 

♦84 16 

♦85 16 

86 15 

♦88 15 

♦89 15 

♦91 16 

♦92 16 

93 15 

♦95 14 

Oregon 

♦94 15 

♦96 15 

♦97 15 

♦98 15 

99 15 

♦100 15 

♦101 15 

102 15 

103 15 

♦104 15 

8 

Owl Creek

Gold River

Courtenay

Sechelt

Chilliwack

Cassidy

Sooke

Republic 

Marblemount

Sedro Woo lley

Darrington

Arlington

Lake Crescent

Perry Creek

Sequim

Louella GS

Forks

Gold Bar

Hoh River

Spokane

Chiwaukum

Chester Morse

Humptulips

Enumclaw

Matlock

Shelton

Cle Elum

Yelm 

Rimrock

Packwood

Randle

Naselle

Castle Rock

Cathlamet

Yale 

Glenwood

Willard

Prindle

Vernonia

Sandy

Cherryville

Hebo

Pine Grove

Grand Ronde

Waldport

Upper Soda

Coquille

Brookings

ft m °N °W pct no. 

503 1 2400 730 52.69 122.43 0 1 

304 1 1600 490 50.93 119.22 0 4 

107 4 700 215 50.33 122.72 25 4 

101 5 300 90 49.75 126.07 25 4 

102 5 220 65 49.70 125.06 75 4 

104 5 600 185 49.51 123.88 60 5 

105 5 550 170 49.07 121.80 75 8 

102 5 650 200 49.06 123.95 33 6 

101 5 150 45 48.40 123.73 67 3 

801 1 2400 730 48.60 118.73 0 3 

402 4\1 400 120 48.58 121.40 25 4 

202 4 200 60 48.53 122.32 83 6 

403 4\1 500 150 48.27 121.63 100 6 

202 4 300 90 48.22 122.07 75 4 

012 4\1 1 305 48.07 124.00 33 3 

403 1 2100 640 48.05 121.47 33 3 

221 5 300 90 48.03 123.03 75 4 

221 5 1 455 48.00 123.08 0 2 

012 4 300 90 47.98 124.40 100 3 

411 4 400 120 47.85 121.65 100 3 

012 4 800 245 47.80 123.97 80 5 

830 1 2200 670 47.78 117.20 0 4 

622 1 1800 550 47.68 120.73 0 5 

412 1\4 2200 670 47.37 121.67 100 5 

030 4 450 135 47.32 123.90 83 6 

412 4 800 245 47.27 121.93 67 3 

030 4 400 120 47.25 123.42 50 4 

231 4 300 90 47.25 123.20 75 4 

631 1\2 2100 640 47.22 121.12 0 6 

232 4 200 60 47.02 122.73 86 7 

641 1 2500 760 46.67 121.03 0 6 

430 1\4 1000 305 46.57 121.70 50 2 

430 1\4 1100 335 46.55 122.05 50 4 

041 5 200 60 46.37 123.73 20 5 

430 6 500 150 46.32 122.87 83 6 

041 5\1 800 245 46.30 123.27 88 8 

440 6\1 400 120 46.00 122.37 100 6 

651 1\3 1 490 46.00 121.17 50 4 

653 3 1800 550 45.80 121.68 20 5 

042 6\3 1500 455 45.62 122.13 83 6 

052 6\1 700 215 45.77 123.22 100 5 

452 6\1 900 275 45.38 122.30 86 7 

451 1\6 2400 730 45.32 122.13 60 5 

053 5\1 600 185 45.22 123.85 80 5 

662 1 2400 730 45.10 121.38 0 5 

251 6\1 700 215 45.10 123.60 50 2 

061 5\1 300 90 44.40 123.87 100 5 

462 1\6 3500 1065 44.38 122.20 20 5 

071 5 400 120 43.20 124.17 33 3 

082 5\1 1200 365 42.12 124.20 60 5 

continues 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
Table 1−Douglas-fir seed sources graded for tree growth in common-garden tests in Spain 

North America Tree Plant Seed source location Seed 

Seed source1, trees, and seed climate source Tests 

Locality zone2 zone3 Altitude Lat Long grade4 used5 

Oregon 

ft m °N °W pct no. 

♦113 15 Mill City 261 6 550 170 44.80 122.70 100 3 

♦114 17 Detroit 462 6\1 1600 490 44.73 122.17 100 2 

♦115 16 Corvallis 262 6 250 75 44.70 123.22 100 2 

♦116 17 Burnt Woods 061 5\1 1100 335 44.60 123.70 100 3 

♦118 15 Marys Peak 061 1\5 3300 1005 44.50 123.57 67 3 

♦119 16 Eugene 252 6\1 700 215 44.02 123.38 67 3 

120 17 Oakridge 482 1 2900 885 43.90 122.37 0 3 

121 15 Steamboat 1 491 1 5250 1600 43.37 122.52 0 2 

122 13 Steamboat 2 491 1 1700 520 43.33 122.70 0 2 

123 16 Roseburg 270 6 1000 305 43.32 123.50 0 2 

124 15 Wolf Creek 511 7\1 1400 425 42.68 123.38 20 5 

♦125 16 Cave Junction 512 7\1 1500 455 42.18 123.67 60 5 

126 15 Ashland 511 1 4900 1495 42.08 122.65 0 3 

California 

127 15 Happy Camp 1 301 1\7 3200 975 41.95 123.50 0 3 

♦128 17 Gasquet 091 17 400 120 41.85 123.98 50 4 

129 19 Seiad Valley 321 1 2800 855 41.80 123.00 25 4 

130 14 Hawkinsville 301 1\7 3500 1065 41.78 123.67 0 3 

131 17 Scott Bar 321 1 3400 1035 41.73 123.10 25 4 

133 16 Happy Camp 2 301 1\7 4100 1250 41.65 123.52 0 3 

134 16 Sawyers Bar 1 311 1 3900 1190 41.28 123.13 0 3 

135 15 Sawyers Bar 2 311 1 4800 1465 41.27 123.15 0 2 

♦136 14 Dunsmuir 521 1\7 3300 1005 41.20 122.30 67 3 

♦137 15 Burney 521 1\7 3350 1020 41.08 121.65 50 2 

138 16 Arcata 1 092 15 1700 520 40.92 123.83 25 4 

139 17 Weaverville 331 1\7 3900 1190 40.90 122.73 0 3 

140 18 Arcata 2 303 15 2900 885 40.90 123.77 33 3 

141 18 Big Bar 1 312 1 4500 1370 40.78 123.20 0 3 

142 15 Big Bar 2 312 1\7 3250 990 40.72 123.30 25 4 

♦143 16 Wildwood 332 1\7 3900 1190 40.38 123.00 50 4 

144 17 Covelo 1 340 7 3000 915 39.92 123.30 0 5 

145 15 Covelo 2 371 1 5100 1555 39.80 122.93 33 6 

147 7 Fort Bragg 094 17 200 60 39.50 123.72 33 3 

148 17 Willits 094 15 1800 550 39.38 123.42 33 3 

♦149 15 Lower Lake 380 7 3100 945 38.83 122.70 100 1 

150 13 Mt St Helena 380 7 2500 760 38.67 122.60 25 4 

KB 4 Fresh Pond 526 1 4100 1250 38.76 120.54 0 4 

NK 33 Georgetown 526 7 2800 855 38.92 120.75 0 2 

NO 20 Ukiah 352 14 1600 490 39.20 123.35 40 5 

♦NP 20 Big River 094 15 200 60 39.32 123.62 67 3 

Mexico 

151 15 Saltillo ―― 1 8250 2515 25.28 100.58 33 3 

152 10 Tlaxco ―― 1 8200 2500 19.60 98.05 0 2 

1 The diamond symbol (♦) marks a source for which mean tree height exceeded plantation height in

half or more of the tests in which the source was assessed. Numbers are IUFRO sources, and

letters, IFG sources; source 151 is P. flahaulti, and 152, P. macrolepis. 2 Lines 1987, Buck and others 1970, USDA Forest Service 1969, 1973. 3 Williamson and others 1987. The backslash symbol (\) shows that the source is located near the 

boundary with the adjoining climate zone. 4 Grade is the percentage of tests in which the source tree height exceeded plantation height. 5 Source was assessed in the number of tests shown. See Appendix table 1.

9 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
Bande and Ochagavía anchored the satellite array contained 81 seedlings set 3 m apart in a 9 by 9 grid, 

and were the largest plantations, receiving 22 and 31 except at La Vecilla where a few sources had 64 or 49 

sources, respectively (table 2). Various other large seedlings per plot, and Conforcal where each plot held 

plantations were located in Lugo, Asturias, León, and a single row of 5 seedlings lined upslope. Every plot 

Guipuzcoa Provinces and received from 9 to 21 sources. was made large enough to carry a small grove of 14 to 

The smallest plantations were located in Lugo and 20 trees to rotation age, except 1 tree each for those at 

Pontevedra Provinces and received four and five sources. Conforcal. 

The plantation design again consisted of three randomized Project scientists staked out and mapped the blocks 

complete blocks of seed source plots, except that at and source plots. Local forestry crews dug the planting 

Conforcal where there were nine blocks. Each plot holes and planted the seedlings. The containers were 

Figure 4―Douglas-fir common-garden tests in northwest 

and north central Spain. The keys show provinces and 

plantations. The diamond symbol (♦) marks a plantation in 

which seed source effects were significant. See table 2 and 

fig. 5. 

10 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
1

cut from the roots just before planting, and every seedling 

was planted with yet another handful of soil from the 

Lourizán arboretum, to ensure mycorrhizal inoculation. 

Seedling survival was scored 1 year after planting, 

and all survivors were cleared of vegetative competition. 

Tree height was measured 5 years after planting, except 

6 years after planting at Conforcal, La Gallina, and La 

Vecilla. Within 7 to 9 years of planting, crown closure 

was imminent in plots of the best seed sources on good 

sites, but edge effects were not discernible in the perimeter 

rows of any plantation. Superior Douglas-firs in these 

common-garden tests illustrate the species potential for 

reforestation in Spain (fig. 5). 

Analyses of Tree Heights 

Taller trees were analyzed to assess seed sources in 

terms of practical plantation silviculture. Douglas-fir is 

intolerant of heavy shade and root competition, and 

rapid early height growth on the planting site is the key 

to seedling and stand establishment. Planted seedlings 

must grow fast enough to overtop and suppress the 

toughest competitors―including grasses, brush, and 

sprouting hardwoods. Saplings that faiI to exceed 1 m in 

height in the first 5 years may never capture the site 

resources. On productive sites, thinning to release 

robust trees and improve wood yields may be done 

within 10 years of planting. Thinning is easier when 

trees are small and is prudent once the fast growers have 

emerged. Research on ponderosa pine (Pinus ponderosa) 

Table 2―Douglas-fir common-garden tests in northwest and north central Spain 

Seed Planting site3 

Province and sources Planting

Plantation2 tested date Altitude Slope Area Lat Long 

no. m pct ha °N °W 

Northwest Spain 

Orense 

♦LH La Hermida 86 Nov 78 700 N 30 6.0 42.52 8.26 

♦SE Sierra del Eje 87 May 78 1360 SW 10 6.0 42.28 6.97 

♦BA Bande 22 Dec 79 900 N 30 4.8 42.03 7.95 

Pontevedra 

♦CD Castro Dozón 5 Nov 80 750 N 5 1.1 42.55 8.05 

Lugo 

RP Rocha da Perdiz 4 Dec 78 520 NE 35 0.9 43.27 7.53 

♦FR Fragavella 20 May 79 580 NW 13 4.4 43.45 7.45 

♦RE Regavella 21 Dec 78 450 flat 4.6 43.27 7.35 

SM Sierra de Meira 14 A p r 8 0 850 SE 8 3.1 43.22 7.23 

♦GA Gamalleira 21 May 80 660 NE 30 4.6 43.27 7.07 

♦VA Valdemadeiro 19 J a n 8 0 920 SW 10 4.2 43.12 6.95 

North central Spain 

Asturias 

♦CO Conforcal 18 A p r 8 1 850 N 55 0.8 43.12 5.88 

♦LG La Gallina 12 A p r 8 1 600 N 10 2.6 43.18 5.84 

León 

♦LV La Vecilla 9 A p r 81 1160 N 30 2.0 42.82 5.36 

Guipuzcoa 

SL Salinas de Léniz 15 Mar 80 900 W 10 3.3 42.98 2.54 

♦AT Ataun 15 Mar 80 750 E 30 3.3 42.97 2.18 

Navarra 

♦OC Ochagavía 31 Mar 80 900 W 40 6.8 42.92 1.05 

1 The test design is three randomized complete blocks of seed source plots, except nine blocks in 

plantation CO. The principal plantations SE and LH received the IUFRO sources, and the 

satellite plantations BA to OC, subsets of the IUFRO and IFG sources. Plantations SE and LH 

had 25 seedlings per plot, and BA to OC, 81, except LV where a few sources had 64 or 49 and 

CO where there were 5 per plot. See Appendix table 1. 2 The diamond symbol (♦) marks a test in which seed source effects were significant. See 

Appendix table 2. 

3 1 m = 3.28 ft; 1 ha = 2.47 acres. 

11 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
in California plantations ranging from 16 to 50 years of 

age has shown that the first trees to reach breast height 

(1.37 m) continue to grow as dominants and codominants 

in the developing stands (Oliver and Powers 1971). 

Seed source effects were assessed in the 15 plantations 

that contained five or more sources (table 2). Analyses 

of variance were run using BMDP program P8V for a 

mixed model with seed sources fixed and trees and 

blocks random (table 3, Jennrich and Sampson 1985). 

Analyses employed first the mean of all trees in each 

source plot and then the 15, 10, and 5 tallest in each 

plot, except the 2 and 1 tallest at Conforcal (Appendix 

table 2). The tall-tree sets represented 60, 40, and 20 

percent of initial stocking in the principal plantations, 

Sierra del Eje and La Hermida, and 18.5, 12.3, and 6.2 

percent of that in the satellite plantations, except 40 and 

20 percent at Conforcal. Sources with fewer trees per 

plot than specified were dropped from analysis. Standard 

errors were computed for the plantation means, and 

one-sided t-tests (p = 0.05) were used to identify those 

sources for which mean tree height significantly exceeded 

plantation height (Steel and Torrie 1960). 

At Sierra del Eje and La Hermida, 87 and 85 sources 

were analyzed using the 5 tallest trees in each source 

plot. At Bande, Castro Dozón, Gamalleira, Valdemadeiro, 

Conforcal, La Gallina, La Vecilla, Salinas de Léniz, 

Ataun, and Ochagavía, all sources were analyzed using 

the 15 tallest trees in each plot, except the 2 tallest at 

Conforcal. Periodic flooding, browsing livestock, and 

wildfire caused high mortality in sources at Regavella, 

Fragavella, and Sierra de Meira. Tree heights for the 

sources and the t-test significant difference were graphed 

for each plantation, using first the mean of all trees in 

each source plot and then that of the 5 or 15 tallest in 

each plot, representing 20 and 18.5 percent of initial 

stocking in the principal and satellite plantations, 

respectively (figs. 6-7). 

In each of the principal and larger satellite plantations, 

sources were ranked by the mean of all trees in each 

source plot and by the means of the 15, 10, and 5 tallest 

in each plot, except the 2 and 1 tallest at Conforcal. The 

stability of source ranking was assessed for each plantation 

separately by calculating coefficients of determination, 

r2, between the source means based on tallest trees and 

those based on all trees. 

Interactions of seed source and planting site were 

assessed in pairs of plantations that had five or more 

sources in common (Appendix tables 3-5). Analyses of 

variance were run using BMDP program P8V for a 

mixed model with seed sources and planting sites fixed 

and trees and blocks random (table 3, Jennrich and 

Sampson 1985). Where seed source-planting site 

interaction was significant (p <0.01 or <0.05), tree heights 

for the sources were graphed by plantation and then 

compared to identify differential responses between the 

sites (figs. 8-9). 

Seed sources were graded for growth performance 

(table 1). The source grade was expressed as the 

percentage of plantations in which tree height for the 

source was numerically greater than plantation height, 

excluding Sierra de Meira and Salinas de Léniz, where 

seed source effects were not significant (Appendix table 

2). Source height was the mean of the 5 or 15 tallest 

trees in each source plot, except the 2 tallest in each plot 

at Conforcal. The principal plantations were counted 

for sources that had 5 or more trees per plot, and the 

satellite plantations, for those that had 15 or more, 

except 2 at Conforcal. 

Table 3―Variance analyses of Douglas-fir in common-garden tests in Spain1 

Plantation (pair) and Degrees 

Source of variation freedom Expected mean squares 

La Hermida 

[2] Seed source, S 84 [5] +5[4] +15[2] 

[3] Block, B 2 [5] +425[3] 

[4] SB 168 [5] +5[4] 

[5] Trees, T(SB) 1020 [5] 

La Hermida<>Sierra del Eje 

[2] Planting site, P 1 [7] +425[4] +1275[2] 

[3] Seed source, S 84 [7] +5[6] +30[3] 

[4] Block,B(P) 4 [7] +425[4] 

[5] PS 84 [7] +5[6] +15[5] 

[6] SB(P) 336 [7] +5[6] 

[7] Trees, T(PSB) 2040 [7] 

1 The examples employ the 5 tallest trees in each seed source plot. Analyses were run 

using BMDP program P8V and mixed models with seed sources and planting sites fixed 

and trees and blocks random (Jennrich and Sampson 1985). 

12 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
A. Seed source differences in tree height and survival after seven growing seasons in Ochagavía

plantation, in the Rio Salazar watershed of the Pirineos in Navarra (March 1987). 

B. Superior performance of trees of seed source 128―Gasquet, northwest 

California―in a 9 x 9 plot in Ochagavía plantation (March 1987). 

Figure 5―Douglas-firs in common-garden tests in northwest and north

central Spain (pages 13-16). See fig. 4 for the plantation locations. continues

13

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993
C. Douglas-firs of a superior seed source after six growing seasons in La Vecilla plantation,

in the Rio Curueño watershed of the Cordillera Cantabrica in León (November 1986). 

D. Seed source differences in tree height and survival in the tenth growing season in

Sierra del Eje plantation, in the Rio Sil watershed in Orense Province (August 1987). 

continues 14 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
E. Seed source differences in tree height and survival after seven growing seasons in 

Bande plantation, in the Rio Limia watershed in Orense Province (September 1986). 

F. Trees showing marked gains in leader length G. Trees of a superior seed source in the eighth 

after six growing seasons in Castro Dozón summer in Gamalleira plantation, in the Rio Eo 

plantation, in the Macizo Galaico Duriense in watershed in Lugo Province (August 1987). continues Pontevedra Province (November 1986). 

15 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
H. Trees of a superior seed source in the tenth I. Douglas-firs gaining on oak sprouts (Quercus 

growing season in Sierra del Eje plantation pyrenaica) after six growing seasons in La

(August 1987). Vecilla plantation (November 1986). 

J. Superior Douglas-fir after seven growing K. Trees of a superior seed source after seven

seasons in Ataun plantation, in the Rio Oria growing seasons in Ochagavía plantation

watershed of the Montes Vascos in (March 1987).

Guipuzcoa Province (November 1986). 

16 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
Results 

Seed source effects were highly significant (p <0.01) 

and significant (p <0.05) in the principal plantations at 

La Hermida and Sierra del Eje, and highly significant in 

the satellite plantations at Bande, Castro Dozón, 

Fragavella, Regavella, Gamalleira, Valdemadeiro, 

Conforcal, La Gallina, La Vecilla, Ataun, and Ochagavía 

(Appendix table 2). Seed source effects were also highly 

significant in 13 plantation pairings: La Hermida against 

Sierra del Eje, Bande, Fragavella, Regavella, Gamalleira, 

Valdemadeiro, La Gallina, Ataun, and Ochagavía, and 

Ochagavía against Bande, Gamalleira, La Gallina, and 

Ataun (Appendix tables 3-5). Seed source-planting site 

interaction was significant in 8 of those 13 pairings: La 

Hermida against Sierra del Eje, Bande, Gamalleira, La 

Gallina, Ataun, and Ochagavía, and Ochagavía against 

Bande and La Gallina. Seed source-planting site 

interaction accounted for one-fifth to one-half the variance 

accounted for by seed source alone. 

Seed Source Effects on Tree 

Height 

In the milder coastal environment of the principal 

plantation at La Hermida, height growth was moderate, 

and seed source accounted for 38 and 27 percent of the 

total variance in analyses using the mean of all trees and 

the 5 tallest trees in each source plot, respectively 

(Appendix table 2). In the harsher interior environment 

of the principal plantation at Sierra del Eje, growth was 

slow, and seed source accounted for about 12 and 8 

percent of the total variance in the respective analyses. 

Growth in the satellite plantations ranged from as 

slow as that at Sierra del Eje up to 2.5 times that at La 

Hermida. Tree height at Bande and Ochagavía, the 

anchor plantations, was superior to that at La Hermida, 

and seed source accounted for larger amounts of the 

total variance. In analyses using the mean of all trees 

and the 15 tallest trees in each source plot, seed source 

accounted for 63 and 47 percent of the variance at 

Bande and for 61 and 41 percent of that at Ochagavía. 

Seed source in respective analyses of the other satellite 

plantations accounted for 72 and 41 percent of the 

variance at Castro Dozón, 58 and 41 percent of that at 

Gamalleira, 75 and 26 percent at Valdemadeiro, 35 and 

29 percent at Conforcal (2 tallest trees in each plot), 51 

and 33 percent at La Gallina, 50 and 36 percent at La 

Vecilla, and 69 and 52 percent at Ataun. 

Planting Site Effects on Tree

Height 

Plantation height ranged from disappointing to 

spectacular, depending on the planting site environment. 

Trees in plantations on the better sites averaged up to 

four times the height of those in plantations on the 

harsher sites. Plantation height after 5 years ranged from 

0.38 m at Sierra del Eje to 1.65 m at Ataun, based on the 

mean of all trees in each source plot (fig. 6), and from 

0.60 to 2.31 m, based on the 5 and 15 tallest in each 

plot in the principal and satellite plantations, respectively 

(fig. 7). Plantation height after 6 years ranged from 0.96 

m at La Vecilla to 1.83 m at Conforcal, based on the 

mean of all trees in each plot, and from 1.51 to 2.26 m 

based on the 15 tallest (2 tallest at Conforcal) in each 

plot. The tall-tree means exceeded breast height (1.37 

m) at Bande, Gamalleira, Conforcal, La Gallina, La 

Vecilla, Salinas de Léniz, Ataun, and Ochagavía. 

Seed Sources Ranked by Tall

Trees 

Within plantations, seed sources were effectively ranked 

by the mean heights of their taller trees. In the principal 

plantations, values of r2 between means based on the 10 

and 5 tallest trees in each source plot and those based 

on all trees, respectively, were 0.969 and 0.951 at La 

Hermida and 0.958 and 0.914 at Sierra del Eje. In the 

satellite plantations, values of r2 between means based 

on the 15 and 10 tallest trees in each plot and those 

based on all trees were 0.959 and 0.954 at Bande, 

0.958 and 0.945 at Gamalleira, 0.976 and 0.981 at La 

Gallina, 0.971 and 0.962 at Ataun, and 0.920 and 

0.912 at Ochagavía. 

Seed Source―Planting Site

Interaction 

Differential growth in tree height was evident in the 

plantation pairs in which analyses showed significant 

seed source-planting site interaction. The graphs show 

that differential responses were pronounced in pairings 

of the principal and satellite plantations, using source 

means based on the 5 and 15 tallest trees in each source 

plot, except the 1 tallest at Conforcal, respectively (figs. 

8-9). In each pair, certain sources grew well on both 

sites, certain others grew poorly on both sites, and still 

others grew well on one site and poorly on the other. 

Tree height of from one in five to one in eight sources 

showed marked upward or downward shifts between 

sites in the pairings of La Hermida with Sierra del Eje, 

Bande, Gamalleira, Conforcal, La Gallina, Ataun, and 

17 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
Ochagavía, and in those of Ochagavía with Bande and 

La Gallina. Pairings that have many sources in common 

illustrate the responses best: 

• La Hermida<>Sierra del Eje: Sources 89 and 113 

were in the top eight on both sites. Sources 51, 77, 

95, and 96 were in the top eight at La Hermida, but 

average at Sierra del Eje. Sources 98 and 118 were in 

the top eight at Sierra del Eje, but below average at La 

Hermida. Sources 48, 65, 68, 82, 99, 130, 133, and 

142 were in the bottom sixteen on both sites. Mexico 

sources 151 and 152 were average at La Hermida and 

below average at Sierra del Eje. 

• La Hermida<>Bande: Sources 97, 101, and 104 

were superior on both sites. Source 40 was superior at 

La Hermida but average at Bande, and source 98 was 

superior at Bande but below average at La Hermida. 

Sources 24, 99, 130, and 134 were poor on both sites. 

• La Hermida<>Gamalleira: Source 91 was superior at 

La Hermida and in the top five at Gamalleira. Sources 

39, 76, 98, and 101 were in the top five at Gamalleira, 

but average or below at La Hermida. Sources 40 and 

143 were average or above at La Hermida, but ranked 

among the poorest at Gamalleira. Sources 78, 102, 

and 133 were poor on both sites. 

• La Hermida<>Conforcal: Sources 91 and 96 were 

top performers on both sites. Source 39 was superior 

to sources 91 and 96 at Conforcal, but average at La 

Hermida. Sources 40 and 89 were among the best at 

La Hermida, but average at Conforcal. Sources 68, 

78, 131, 139, and 141 were poor on both sites. 

• La Hermida<>Ochagavía: Sources 51, 53, 72, 73, 

89, 95, and 96 were top performers on both sites. 

Sources 77 and 91 were superior at La Hermida, but 

average at Ochagavía. Sources 54 and 128 were 

superior and sources 34, 39, 50, 85, 94, 97, and 145 

were among the best at Ochagavía, but all were 

average or lower at La Hermida. Sources 68, 82, and 

99 were the poorest on both sites. 

Figure 6―Seed source effects on Douglas-fir height after 

5 and 6 years in common-garden tests in Spain (pages 18- 21). Source tree height is shown as the mean of all trees in 

each source plot. Centers of the graphs for Sierra del Eje 

and La Hermida, the principal plantations, are expanded to 

show every source. The graphs for Bande to Ochagavía, the satellite plantations, are arrayed from Portugal to France. 

The side bar shows plantation height, and the bracket, 

significant difference (p = 0.05). 

18 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
19 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
20 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
21 

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22 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 

Figure 7―Seed source effects on Douglas-fir height after 5 and

6 years in common-garden tests in Spain (pages 22-23). Source 

tree height is shown as the mean of the 5 tallest trees in each

source plot at Sierra del Eje and La Hermida, the principal

plantations (n = 15), and the 15 tallest in each plot in the satellite

plantations (n = 45), except the 2 tallest in each plot at Conforcal

(n = 18). Graphs are grouped to show plantation heights <1.1 m

on harsh sites and >1.4 m on good sites. The side bar shows

plantation height, and the bracket, significant difference (p = 0.05). 
23 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
Seed Source Grades and Climate 

Zones 

Forty-four of the 91 seed sources graded from 50 to 

100 percent, that is, had mean tree heights greater than 

plantation height on half or more of the sites on which 

they were assessed (table 1). Twenty-one of these came 

from stands in regions where the Pacific Ocean air mass 

dominates climate, plant climate zones 4, 5, and 6 

(Williamson and others 1987). Another 18 came from 

inland stands that receive maritime influence, stands 

situated in the watersheds of rivers that flow westward to 

the Pacific Ocean through plant climate zones 4, 5, and 

6. The 18 are listed in climate zones 4\1 or 1 \4, 5\1 or 

1 \5, and 6\1 or 1 \6, depending on whether their map 

coordinates place them just west or east of the boundary 

of plant climate zone 1, which covers those regions 

where the continental air mass prevails. The remaining 

five sources came from stands in areas of interior-valley 

climate, plant climate zone 7. 

Of the 47 sources that graded below 50 percent, 25 

graded zero, that is, consistently had mean tree heights 

less than plantation height. Sixteen of these came from 

stands in regions of continental climate, plant climate 

zone 1, and four, from stands in climate zone 1 \7. The 

other five came from stands in areas of interior-valley or 

Pacific Ocean influence, plant climate zone 7 or climate 

zones 5, 6, and 15. In the next-to-lowest category, 12 

sources graded 20 to 25 percent, and almost all of them 

came from stands in regions of continental influence, 

plant climate zone 1. 

In general, slow growth characterized seed sources 

from latitudes north of 50° N, interior British Columbia, 

regions east of the crest of the Cascade Ranges in 

Washington and Oregon (var. glauca), latitudes south of 

44° N, high altitudes west of the crest of the Cascade 

Ranges and the Sierra Nevada (var. menziesii), and 

eastern Mexico (P. flahaulti, P. macrolepis). Physiographic 

distributions of the best and poorest sources, as judged 

by source grade, may be summarized as follows (see 

table 1): 

• British Columbia: The best four sources are situated 

in Pacific coastal regions south of latitude 50° N, at 

altitudes of 45 to 185 m above sea level on Vancouver 

Island and the mainland. Three of the four poorest 

sources are situated at altitudes of 215 to 730 m in 

coastal and inland regions north of latitude 50° N. 

• Washington: The best 20 sources are situated in 

regions of Pacific Ocean influence, including source 

53 in the Sauk River watershed, source 72 in the 

Cedar watershed, sources 84 and 85 in the Cowlitz, 

source 89 in the Elochoman, source 91 in the Lewis, 

and source 92 in the Klickitat on the east slope of the 

Cascade Range just north of the Columbia River. The 

24 

20 range in altitude from 60 to 455 m, except source 

92 at 490 m. Five of the six poorest sources are 

situated at altitudes of 550 to 760 m in continental 

regions east of the crest of the Cascade Range. 

• Oregon: Thirteen of the best 14 sources are situated 

in regions of Pacific Ocean influence, including source 

94 in the Nehalem River watershed, sources 96 and 

97 in the Clackamas and Sandy watersheds, source 

98 in the Nestuca, source 100 in the South Yamhill, 

source 101 in the Alsea, source 104 in the Chetco, 

source 114 in the Santiam, source 116 in the Yaquina, 

source 118 in the North Fork Alsea, and source 119 in 

the Long Tom. Only one is situated in an area of 

interior-valley influence, source 125 in the Illinois 

River watershed in the Klamath Mountains. The 14 

range in altitude from 75 to 730 m, except source 118 

at 1005 m on the coastal side of the Oregon Coast 

Range. The six poorest sources are situated in areas of 

continental influence, five at altitudes of 520 to 1600 

m in the Cascade Range and one at 1495 m in the 

Klamath Mountains. 

• California: Two of the best six sources are situated in 

the coastal North Coast Range, and three others, in 

areas of interior-valley influence in the Cascade Range 

and Klamath Mountains―sources 136,137, and 143 

in the watersheds of the Sacramento, Pit, and South 

Fork Trinity Rivers, respectively. The coastal sources 

are at altitudes of 60 and 120 m, and the inland 

sources, at 1005 to 1 190 m. Eight of the 10 poorest 

sources are situated in areas of continental influence―

seven at altitudes of 975 to 1465 m in the Klamath 

Mountains and one at 1250 m in the Sierra Nevada. 

The other two are situated in areas of Pacific Ocean 

and interior-valley influence, at 915 m in the North 

Coast Range and 855 m in the Sierra Nevada. 

Figure 8―Seed source-planting site interaction effects on

Douglas-fir height after 5 years in the principal plantations 

at Sierra del Eje and La Hermida, northwest Spain (page 

25). Source tree height is shown as the mean of the 5

tallest trees in each source plot (n = 15). Lines between 

the arrays show that certain sources grew better on one 

site than on the other. The side bar shows plantation

height, and the bracket, significant difference (p = 0.05). 

Figure 9―Seed source-planting site interaction effects on

Douglas-fir height after 5 and 6 years in the principal

plantation at La Hermida and satellite plantations on better

sites, northwest and north central Spain (pages 26-27).

Source tree height is shown as the mean of the 5 tallest 

trees in each source plot at La Hermida (n = 15), the 15

tallest in each plot at Bande, Gamalleira, and Ochagavía

(n = 45), and the 1 tallest in each plot at Conforcal (n = 9). 

Lines between the arrays show that certain sources grew 

better on one site than on the other. The side bar shows 

plantation height, and the bracket, significant difference 

(p = 0.05). 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
25 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
26 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
27 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
Discussion 

Early height growth in common-garden tests of Douglasfir shows that Pacific Slope seed sources promise rapid 

plantation establishment in coastal and inland regions 

of northwest and north central Spain. Superior sources 

for Spain are clustered in regions where climate is 

dominated by the Pacific Ocean air mass. Pacific climate 

types characterize maritime slopes along the Georgia 

Strait in southwest British Columbia, the Olympic 

Peninsula, and the Coast Ranges of Washington, Oregon, 

and northwest California. Inland, they characterize 

lower slopes of the Olympic Mountains and the Coast 

and Cascade Ranges facing the Puget Trough in western 

Washington and Willamette Valley in northwest Oregon. 

Best Seed Sources Defined 

Promising seed sources are those that graded 50 to 

100 percent (table 1, fig. 10). These sources span 11 ° of 

latitude in coastal forests―from 39° N in the North 

Coast Range of northwest California to 50° N along the 

Georgia Strait of southwest British Columbia―and 8° in 

inland forests―from 41 ° N in the Klamath Mountains of 

northwest California to just above 49° N near the lower 

Fraser River in southwest British Columbia. They represent 

altitudes of 45 to 365 m (1005 m) along the Pacific 

Coast, 75 to 730 m in the Olympic Mountains and Coast 

and Cascade Ranges facing the Puget Trough of western 

Washington and Willamette Valley of northwest Oregon, 

and 455 to 1190 m in the Klamath Mountains and 

Cascade Ranges of southwest Oregon and northwest 

California. 

Thirty-one of the 36 sources that graded 60 to 100 

percent are found in Pacific Slope forests north of latitude 

44° N and at altitudes of 45 to 1005 m above sea level. 

The other five are found south of 42.5° N, in the Oregon 

Coast Range at 365 m, the North Coast Range at 60 and 

945 m, and the Klamath Mountains at 455 and 1005 m. 

Twenty-five of the 26 sources that graded 75 to 100 

percent are found north of 44° N and at altitudes of 60 to 

670 m. 

Seed Source Climates Typed 

The most promising seed sources are situated in habitats 

characterized by long growing seasons, favorable water 

regimes, soils of good drainage, and cold but not harsh 

winters (Franklin and Dyrness 1973, Williamson and 

others 1987). Pacific Ocean influence typifies climates 

at seed origin and largely explains the broad latitudinal 

and low altitudinal distributions of superior sources in 

the common-garden tests. Taken together, the extent of 

Pacific climate types and the distribution of seed zones 

of known superior sources allow us to delimit forest 

regions within which we may collect Douglas-fir of high 

potential for reforestation in Spain. 

Climates at seed origin of the sources tested in Spain 

fall into six distinct climate types. These types relate 

plant climate zones (Williamson and others 1987) to 

Douglas-fir forests in a north-south, coast-inland, and 

altitudinal format. Pacific climate types A through C 

characterize the fast growers, and Pacific type D, interiorvalley type E, and continental type F, the average and 

slow growers. Pacific types A―C have long growing 

seasons and beneficially cold winters. The winters are 

normally colder in types A―C and E than in type D and 

are longest and coldest in type F. The types may be 

summarized as follows (parentheses show related plant 

climate zones): 

• A (zone 5): Pacific Ocean air brings relatively warm 

winters to coastal regions from southwest British 

Columbia to northwest California and effectively 

enhances forest growth. Growing seasons extend up 

to 250 days and longer in areas near salt water, 

including the southern end of Vancouver Island and 

coastal slopes of the Olympic Peninsula and Oregon 

Coast Range. Winter lows in these regions range from 

―2° to ―18° C. 

• B (zone 4): Inland regions west of the Washington 

Cascades are influenced primarily by the Pacific Ocean 

and Puget Sound, and at times by high altitudes and 

the continental air mass. These regions differ from 

neighboring coastal regions in having shorter growing 

seasons, greater rainfall, and colder winters. Winter 

lows range from ―7° to ―22° C. 

• C (zones 6, 3): Uplands adjoining the Puget Trough 

in western Washington and the Willamette Valley in 

northwest Oregon get maritime influence much of the 

year. Pacific Ocean air spills inland along the Columbia 

River and low passes through the Coast Ranges and 

penetrates eastward to middle slopes of the Cascade 

Ranges. Growing seasons are longer and warmer in 

these regions than around Puget Sound, but rainfall is 

as great and winters are as cold. Winter lows range 

from ―7° to ―22° C. 

28 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
• D (zones 17, 15, 14): California's coastal North Coast 

Range is dominated almost totally by Pacific Ocean 

air. Growing seasons are long, summers are cool and 

foggy, and winters are wet and cool. Record lows 

range from ―1 ° to ―7° C. Away from the coast, Pacific 

Ocean influence still prevails 85 percent of the time. 

Winters in the North Coast Range are coldest on the 

ridgetops and in the valley and canyon bottoms. 

Record lows inland range from―7° to ―12° C. 

• E (zone 7): Inland regions west of the Cascade Range―

Sierra Nevada in southern Oregon and northern 

California, in watersheds of the Rogue, Klamath, Trinity, 

and Sacramento Rivers, have interior-valley climates. 

The growing seasons are long, summers are hot and 

dry, and winters are pronounced. Record lows here 

range from ―9° to ―18° C. 

• F (zones 1, 2): At high altitudes to the west and in 

regions east of the crest of the Cascade Range―Sierra 

Nevada, the continental air mass dominates supremely. 

Growing seasons are mostly short, ranging from 90 

days or less up to 150 days. Winters are severe and 

snowpacks are the rule. Record lows range from ―19° 

to ―37° C. 

Cold winters and hard freezes at seed origins explain 

the freeze-hardy growth of even the most coastal sources 

of Douglas-fir on cold inland sites in Spain, including 

those at Sierra del Eje, La Vecilla, and Ochagavía (fig. 3, 

table 2). The Pacific and interior-valley climates of 

western Washington, western Oregon, and northern 

California match those of the Iberian Peninsula so closely 

that Douglas-fir may have greater potential in Spain and 

Portugal than in the rest of western Europe. 

European Findings Compared 

Douglas-fir is the most successful North American 

tree in Europe, with vigorous stands in 24 countries 

(Hermann 1987). Douglas-fir plantations in France, 

Germany, and Great Britain already cover 220,000, 

80,000, and 46,000 hectares, respectively (Hermann 

1987, Lines 1987). Current planting rates suggest that 

France could have 500,000 hectares in Douglas-fir by 

the year 2020. West Germany may plant Douglas-fir on 

up to 20 percent of its forested area, where it yields 

double the volume of Scotch pine and 30 percent more 

volume than Norway spruce (Hermann 1987). Greater 

timber values and growth rates will promote a wider use 

of Douglas-fir in Britain, too, as emphasis shifts from 

forestation to replanting of the sheltered valley sites that 

now carry Scotch pine and European larch (Lines 1987). 

The successes of Douglas-fir in Britain, Germany, and 

France have been shown to depend on seed source, and 

Spain's common-garden tests have largely confirmed 

the findings in those countries. In the common-garden 

tests of IUFRO seed sources in Scotland, mean tree 

height and stem diameter after 10 years showed that the 

fastest growers came from coastal slopes and foothills of 

the Olympic Mountains and western Cascade Ranges in 

Washington and a few areas at low altitudes in western 

Oregon. Growth was moderate for sources from 

Vancouver Island and poor for sources from latitudes 

north of 50° and south of 44° N. Seed sources advocated 

for Britain are those situated below 800 m in seed zones 

012, 041, 222, 240, 202, 403, 411, and 412 in western 

Washington, seed zone 072 in south coastal Oregon, 

and seed zone 103 on the north end of Vancouver 

Island (Lines 1987). 

Findings in Britain differ little from those in Germany 

or France. The results in 12 trials that were begun in 

Germany in the period from 1910 to 1978 showed that 

the fastest growers came from seed sources in the coastal 

forests of Washington and southwest British Columbia 

and inland forests at low altitudes in the western 

Washington Cascades (Kleinschmit 1984, cited in 

Hermann 1987). After 13 years in the tests of 131 

IUFRO sources in France, the best 63 sources (48 percent) 

had mean tree heights of 7.2 to 8.4 m. All 63 of them 

came from Pacific Slope forests, counting 16 in British 

Columbia, 37 in Washington, and 10 in Oregon. Sixtytwo of the best came from stands at altitudes below 600 

m, and 59 of them, from coastal and inland regions 

between latitudes 44° and 50° N (Roman-Amat 1987). 

Findings in Spain differ from those in Britain, Germany, 

and France in terms of substantial southward shifts and 

appreciable altitudinal extensions of promising seed 

origins. Of Spain's best 44 sources (48 percent), British 

Columbia yielded 4; Washington, 20; Oregon, 14; and 

California, 6 (table 1). Seven of the best sources came 

from regions south of 43° N, three from the Oregon 

Coast and North Coast Ranges and four from the Klamath 

Mountains and California Cascades. Six of the best 

came from altitudes higher than 600 m: one from 670 m 

in Washington, two from 730 and 1005 m in Oregon, 

and three from 945 to 1190 m in California. 

Differences aside, three-fourths of the best sources for 

Spain are the same as those for France. Most of the fast 

growers are concentrated between latitudes 44° and 50° 

N and at altitudes of 60 to 730 m on the Pacific Slope, in 

regions where the Pacific Ocean air mass dominates 

climate. 

29 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
Figu

re 10―Douglas-fir seed sources in Pacific North 

America suggested for use in tree planting programs in 

Spain (♦). The key lists sources by physiographic region, 

tree seed zone, and altitude. Fast growers are found in the 

coastal forests from northwest California to the Georgia 

Strait in southwest British Columbia, and in the inland 

forests on lower slopes of the Olympic Mountains and the 

Coast and Cascade Ranges facing the Puget Trough in 

western Washington and Willamette Valley in northwest 

Oregon, regions where the Pacific Ocean air mass dominates 

climate. 

30 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
31 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
Implications for Reforestation 

in Spain 

To ensure Douglas-fir of high growth potential for 

reforestation in the coastal and inland regions of northern 

Spain, seed sources should be selected in Pacific Slope 

forests in Pacific climate types A―C. Spain's commongarden tests show that most of the best sources for Spain 

are situated at latitudes of 44° to 50° N and altitudes of 

60 to 700 m in coastal and inland regions west of the 

crest of the Cascade Ranges. The best coastal sources 

are found along the southern Georgia Strait of southwest 

British Columbia and on lower slopes of the Olympic 

Peninsula and Coast Ranges of Washington, Oregon, 

and northwest California. The best inland sources are 

found on lower slopes of the Olympic Mountains and 

Coast and Cascade Ranges facing the Puget Trough in 

western Washington and Willamette Valley in northwest 

Oregon, except the few in southwest Oregon and 

northwest California. 

To identify seed zones for future Douglas-fir collections, 

we marked the origins of the 44 best seed sources (♦) 

determined in the common-garden tests (fig. 10, table 

1). The resulting map distributions show that most of the 

best sources are located in contiguous regional sets of 

neighboring seed zones. Known source performances 

recommend seed collections from stands in southwest 

British Columbia, western Washington, and northwest 

Oregon, in the seed zones and altitudes listed below: 

• Southwest British Columbia: seed zones 101, 102, 

104, and 105 at altitudes of 45 to 185 m 

• Western Washington: seed zones 012, 030, 041, 

042, 202, 221, 231, 232, 403, 411, 412, 430, and 

440 at altitudes of 60 to 455 m, even 670 m in zone 

412 

• Northwest Oregon: seed zones 052, 053, 061, 251, 

252, 261, 262, 451, 452, and 462 at altitudes of 90 to 

490 m, even 1005 m in zone 061 

Certain seed zones in southwest Oregon and northwest 

California should also be targeted, to produce seedlings 

for planting on sites that are similar to those of plantations 

in which trees of the particular sources grew well. Known 

source performances recommend seed collections from 

stands at altitudes of 60 to 365 m in coastal seed zones 

082, 091, and 094, and at 455 to 1190 m in inland seed 

zones 512, 332, and 521. 

32 

Trees of many of the best seed sources grew well on 

diverse planting sites (figs. 8-9). Sources 32, 39, 51, 53, 

54, 60, 62, 63, 64, 72, 73, 77, 80, 88, 89, 91, 94, 95, 96, 

98, 101, 113, 114, 115, and 116, for example, are 

characterized by broad adaptability. Their consistently 

good growth shows that they may be safely used on 

almost any planting site. Trees of some of the other best 

sources, however, grew well on one site and poorly on 

another. Best sources that show differential growth 

performance, such as sources 34, 40, 58, 98, 100, 118, 

128, and 145, may be considered safe to plant wherever 

the soils and climates are similar to those in which trees 

of the particular source grew well. 

Whenever possible, Douglas-fir stands in Spain's target 

seed zones―and any stands to be collected in adjacent 

zones―should be located at altitudes close to those of 

the known seed sources (table 1). Seed collections 

should represent 20 or more trees that are near planned 

harvest age, spaced about 185 m apart, and chosen for 

health, form, vigor, and abundance of cones in the top 

third of the live crown. Mature cones should be picked 

in years when the crops are moderate to heavy, in order 

to enhance seed quality, obtain large seed lots of broad 

genetic base, and supply selection differentials for the 

improvement of timber traits (Kitzmiller 1976). 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
References 

Barner, H. 1971. Procurement of Douglas fir seed for 

provenance research. In: Report of the second session of 

the FAO panel of experts on forest gene resources; 1971 

March 10-12; Macon, GA. New York: Food and Agriculture 

Organization of the United Nations; 67. 

Buck, John M.; Adams, Ronald S.; Cone, Jerrold; Conkle, M. 

Thompson; Libby, William J.; Eden, Cecil J.; Knight, Michel 

J. 1970. California tree seed zones. San Francisco: 

California Region, Forest Service, U.S. Department of 

Agriculture; 5 p. 

Fernandez, J.; Michel, M. 1982. Primeros resultados de 

crecimiento de Chamaecyparis lawsoniana en tres 

estaciones del norte de España. In: Proceedings INIAIUFRO Reunion Tecnica Principios de Introducción de 

Especies; 1982 October 4-8; Lourizán, España. Pontevedra, 

España: Departamento Forestal de Zonas Húmedas, Instituto 

Nacional de Investigaciones Agrarias (INIA-CRIDA 01 

Lourizán), Ministerio de Agricultura, Pesca y Alimentación; 

21 p. 

Franklin, Jerry F.; Dyrness, C. T. 1973. Natural vegetation of 

Oregon and Washington. Gen. Tech. Rep. PNW-8. 

Portland, OR: Pacific Northwest Forest and Range Experiment 

Station, Forest Service, U.S. Department of Agriculture; 

417 p. 

Hermann, Richard K. 1987. North American tree species in 

Europe. Journal of Forestry 85(12): 27-32. 

ICONA. 1975. Tecnicas de forestacion. Madrid, España: 

Instituto Nacional para la Conservacion de la Naturaleza 

(ICONA), Publicaciones del Ministerio de Agricultura. 

Instituto Geografico Nacional. 1982. Mapa del Camino de 

Santiago. Scale 1:600000. Madrid, Spain: Instituto 

Geografico Nacional, General Ibañez de Ibero, 3. 

Jennrich, Robert; Sampson, Paul. 1985. P8V. In: Dixon, W. 

J., and others, eds. BMDP statistical software manual. 

Berkeley, CA: University California Press; 427-435. 

Kitzmiller, Jay H. 1976. Tree improvement master plan for 

the California region. San Francisco, CA: Pacific Southwest 

Region, Forest Service, U.S. Department of Agriculture; 

123 p. 

Lines, R. 1987. Choice of seed origins for the main forest 

species in Britain. Forestry Commission Bulletin 66. London, 

United Kingdom: Her Majesty's Stationery Office; Forestry 

Commission, Forest Research Station, Alice Holt Lodge, 

Wrecclesham, Farnham, Surrey; 61 p. 

Montero de Burgos, José Luis; González Rebollar, José Luis. 

1974. Diagramas bioclimaticos. Madrid, España: Instituto 

Nacional para la Conservacion de la Naturaleza (ICONA); 

Publicaciones del Ministerio de Agricultura; 379 p. 

Oliver, William W.; Powers, Robert F. 1971. Early height 

growth of ponderosa pine forecasts dominance in 

plantations. Res. Note PSW-250. Berkeley, CA: Pacific 

Southwest Forest and Range Experiment Station, Forest 

Service, U.S. Department of Agriculture; 4 p. 

Pardos Carrión, José A.; Gil Sanchez, Luis A. 1986. Los 

huertos semilleros: estudios basicos para su establecimiento 

en España. Monografias 44. Madrid, España: Instituto 

Nacional para la Conservacion de la Naturaleza (ICONA), 

Ministerio de Agricultura, Pesca y Alimentación; 1 28 p. 

Roman-Amat, B. 1987. Provenances de Douglas: les derniers 

résultats de l'Inra. Forêt-Entreprise 44(Juin): 26-31. 

Steel, Robert G. D.; Torrie, James H. 1960. Principles and 

procedures of statistics. New York: McGraw-Hill; 481 p. 

Toval, G. 1983. Utilización de la corteza de pinos como 

substrato en viveros. Madrid, España. An. INIA Serie 

Forestal l 7: 67-81. 

Toval, G. 1985. Results in two test sites of provenances of 

the IUFRO collection of Pseudotsuga menziesii (Mirb.) 

Franco in Galicia. In: Proceedings IUFRO working party 

on breeding strategy for Douglas-fir as an introduced species. 

Working Party S.2.02.05; 1985 June; Vienna, Austria. 

Pontevedra, España: Departamento de Investigación Forestal 

de Lourizán, Consellería de Agricultura, Pesca y 

Alimentación, Xunta de Galicia; 20 p. 

Toval, G.; Puerto, G.; Para, J. M. 1982a. Enraizamiento de 

esquejes de Sequoia sempervirens. In: Proceedings INIAIUFRO Reunion Tecnica Principios de Introducción de 

Especies; 1982 October 4-8; Lourizán, España. Pontevedra, 

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de procedencias de Pseudotsuga menziesii en Galicia 

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Principios de Introducción de Especies; 1982 October 4-8; 

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Ministerio de Agricultura, Pesca y Alimentación; 55 p. 

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Scale 1:1000000. San Francisco: California Region, Forest 

Service, U.S. Department of Agriculture. 

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seed zone maps. Scale 1:500000. Portland, OR: Pacific 

Northwest Region, Forest Service, U.S. Department of 

Agriculture. 

Williamson, Joseph F.; Dunmire, John R.; Zimmerman, Maureen 

Williams; Edinger, Philip; eds. 1987. The western garden 

book. Menlo Park, CA: Lane Publishing Co.; 512 p. 

Williamson, Richard L.; Twombly, Asa D. 1983. Pacific 

Douglas-fir. In: Burns, Russell M., tech. comp. Silvicultural 

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Agric. Handb. 445. Washington, DC: U.S. Department of 

Agriculture, Forest Service; 191 p. 

33 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
Appendix Tables 

Table 1―Allocation of Douglas-fir seed sources among common-garden tests in Spain1 

Spain region and plantation4 

North America Tree 

Seed source2 and seed Northwest North central 

Locality zone3 SE LH BA CD FR RE SM GA VA CO LG LV SL AT OC 

British Columbia 

3 Alexandria 503 + + ― ― ― + ― ― ― ― ― ― ― ― ―

14 Eagle Bay 304 + + + ― ― ― + ― ― ― ― ― ― ― + 

24 Owl Creek 107 † + + ― ― ― + ― ― ― ― ― ― ― + 

31 Gold River 101 + + ― ― † ― ― ― ― ― ― ― ― + ―

♦32 Courtenay 102 + † ― ― ― † ― † ― ― ― ― ― ― ―

♦34 Sechelt 104 + + ― ― ― ― ― † ― † ― ― ― ― † 

♦39 Chilliwack 105 + + ― ― † ― ― † † † ― ― + † † 

40 Cassidy 102 † † + ― ― ― ― + + + ― ― + ― ―

♦45 Sooke 101 + † ― ― ― † ― ― ― ― ― ― ― ― ―

Washington 

48 Republic 801 + + ― ― + ― ― + ― ― ― ― ― ― ― 50 Marblemount 402 + + ― ― ― ― ― ― ― ― + ― ― ― † 

♦51 Sedro Wooley 202 + † ― ― ― † ― † ― ― ― † ― ― † 

♦53 Darrington 403 † † ― ― ― ― ― ― † ― ― † + † † 

♦54 Arlington 202 + † ― ― + ― ― ― ― † ― ― ― ― † 

58 Lake Crescent 012 † + ― ― + ― ― ― ― ― ― ― ― ― ―

59 Perry Creek 403 + † + ― ― ― ― ― ― ― ― ― ― ― ―

♦60 Sequim 221 † + † ― ― ― ― ― ― † ― ― ― ― ―

61 Louella GS 221 + + ― ― ― ― + ― ― ― ― ― ― ― ―

♦62 Forks 012 † † ― ― ― ― ― ― ― ― † ― ― ― -―

♦63 Gold Bar 411 † † ― ― ― ― ― † ― ― ― ― ― ― ―

♦64 Hoh River 012 † † † ― † ― + ― + ― ― ― ― ― ―

65 Spokane 830 + + + ― + ― ― ― ― ― ― ― ― ― ―

68 Chiwaukum 622 + + ― ― ― ― ― ― ― + + ― ― + + 

♦72 Chester Morse 412 † † ― † ― ― ― ― ― ― ― † ― ― † 

♦73 Humptulips 030 † † ― ― † + + ― ― ― ― ― + † † 

♦75 Enumclaw 412 † + ― ― ― ― + ― † ― ― ― ― ― ―

♦76 Matlock 030 + + † ― ― ― ― † ― ― ― ― ― ― ―

♦77 Shelton 231 + † ― ― ― ― ― ― ― ― ― † ― ― † 

78 Cle Elum 631 + + + ― ― ― ― + ― + + ― ― ― ―

♦80 Yelm 232 † † † † ― ― + † ― ― ― ― + † + 

82 Rimrock 641 + + ― ― ― ― + ― ― ― + + ― + + 

♦84 Packwood 430 + † ― ― ― ― ― ― ― ― ― ― ― ― ―

♦85 Randle 430 † + ― ― ― ― ― ― ― ― + ― ― ― † 

86 Naselle 041 + + ― ― + † ― ― ― ― ― + + ― ―

♦88 Castle Rock 430 + † ― ― ― ― ― † ― ― † ― ― † † 

♦89 Cathlamet 041 † † ― † ― ― ― ― † + ― † + † † 

♦91 Yale 440 † † ― ― ― ― ― † ― † ― † ― ― † 

♦92 Glenwood 651 † + ― ― † ― ― ― ― ― ― ― ― ― + 

93 Willard 653 + + ― ― ― ― ― ― † ― ― ― ― + + 

♦95 Prindle 042 + † ― † ― ― + † ― ― ― ― + † † 

Oregon 

♦94 Vernonia 052 † † ― ― † ― + ― ― ― ― ― ― † † 

♦96 Sandy 452 + † ― ― ― † ― ― ― † † ― + † † 

♦97 Cherryville 451 † † † ― ― ― ― ― ― ― ― ― + + † 

♦98 Hebo 053 † + † ― ― ― ― † † ― ― ― ― ― ―

99 Pine Grove 662 + + + ― + ― ― ― ― ― ― ― ― ― + 

♦100 Grand Ronde 251 + † ― ― + ― ― ― ― ― ― ― + ― ―

continues 

34 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
Table 1―Allocation of Douglas-fir seed sources among common-garden tests in Spain1 

Spain region and plantation4 

North America Tree 

Seed source2 and seed Northwest North central 

Locality zone3 SE LH BA CD FR RE SM GA VA CO LG LV SL AT OC 

Oregon 

♦101 Waldport 061 † † † ― ― ― ― † † ― ― ― ― ― ―

102 Upper Soda 462 † + ― ― ― ― ― + + ― ― ― ― ― + 

103 Coquille 071 + + ― ― + † ― ― ― ― ― ― ― ― ―

♦104 Brookings 082 + † † ― ― + ― † ― ― ― ― + ― ―

♦113 Mill City 261 † † ― ― ― ― ― ― † ― ― ― ― ― ―

♦114 Detroit 462 † † ― ― ― ― ― ― ― ― ― ― ― ― ―

♦115 Corvallis 262 † † ― ― ― ― ― ― ― ― ― ― ― ― ―

♦116 Burnt Woods 061 † † ― ― † ― ― ― ― ― ― ― + ― ―

♦118 Marys Peak 061 † + ― ― ― ― ― ― ― † ― ― ― ― ―

♦119 Eugene 252 † † ― ― ― + ― ― ― ― ― ― ― ― ―

120 Oakridge 482 + + ― ― ― + ― ― ― ― ― ― ― ― ―

121 Steamboat 1 491 + + ― ― ― ― ― ― ― ― ― ― ― ― ―

122 Steamboat 2 491 + + ― ― ― ― ― ― ― ― ― ― ― ― ―

123 Roseburg 270 + + ― ― ― ― ― ― ― ― ― ― ― ― ―

124 Wolf Creek 511 † + + ― ― + ― ― ― ― ― ― ― ― + 

♦125 Cave Junction 512 † + ― ― † + ― ― † ― ― ― ― ― ―

126 Ashland 511 + + ― ― ― + ― ― ― ― ― ― ― ― ―

California 

127 Happy Camp 1 301 + + ― ― ― + ― ― ― ― ― ― ― ― ―

♦128 Gasquet 091 + + ― ― † ― + ― ― ― ― ― ― ― † 

129 Seiad Valley 321 + + ― ― ― + + ― † ― ― ― ― ― ―

130 Hawkinsville 301 + + + ― ― ― ― ― ― ― ― ― ― ― ―

131 Scott Bar 321 † + ― ― ― + ― ― ― + ― ― ― ― ―

133 Happy Camp 2 301 + + ― ― ― ― ― + ― ― ― ― ― ― ―

134 Sawyers Bar 1 311 + + + ― ― ― ― ― ― ― ― ― ― ― ―

135 Sawyers Bar 2 311 + + ― ― ― ― ― ― ― ― ― ― ― ― ―

♦136 Dunsmuir 521 + † ― ― † ― ― ― ― ― ― ― ― ― ―

♦137 Burney 521 † + ― ― ― ― ― ― ― ― ― ― ― ― ―

138 Arcata 1 092 † + ― ― ― + ― ― ― + ― ― ― ― ―

139 Weaverville 331 + + ― ― ― ― ― ― ― + ― ― ― ― ―

140 Arcata 2 303 + + † ― ― ― ― ― ― ― ― ― ― ― ―

141 Big Bar 1 312 + + ― ― ― ― ― ― ― + ― ― ― ― ―

142 Big Bar 2 312 + + ― ― ― ― ― ― † + ― ― + ― ―

♦143 Wildwood 332 † † ― ― ― ― + + ― ― ― ― ― ― + 

144 Covelo 1 340 + + + ― ― + ― ― ― ― ― ― ― ― + 

145 Covelo 2 371 † + ― ― ― ― ― ― + ― + ― ― + † 

147 Fort Bragg 094 + † ― ― + ― ― ― ― ― ― ― + ― ―

148 Willits 094 + + ― ― ― † + ― ― ― ― ― ― ― ―

♦149 Lower Lake 380 † ― ― ― ― ― ― ― ― ― ― ― ― ― ―

150 Mt St Helena 380 + + ― ― ― + ― ― ― ― † ― ― ― ―

KB Fresh Pond 526 ― ― ― ― ― ― + + + + ― ― ― ― ―

NK Georgetown 526 ― ― + ― ― ― ― ― + ― ― ― ― ― ―

NO Ukiah 352 ― ― † + ― ― ― + † + ― ― ― ― ―

♦NP Big River 094 ― ― ― ― ― ― ― ― † ― † + ― ― ―

Mexico 

151 Saltillo ―― + † ― ― + ― ― ― ― ― ― ― ― ― ―

152 Tlaxco ―― + + ― ― ― ― ― ― ― ― ― ― ― ― ―

1 The symbols (+, †) show where each source was assessed, and (†), where mean tree height for the 

source exceeded plantation height. See figs. 2-3 and table 1. 2 The diamond symbol (♦) marks a source for which mean tree height exceeded plantation height in 

half or more of the tests in which the source was assessed. See Appendix table 2. 3 Lines 1987, Buck and others 1970, USDA Forest Service 1969, 1973. 4 The letter codes SE and LH represent the principal plantations, and BA through OC, the satellite 

plantations. See fig. 4 and table 2. 

35 

USDA Forest Service Gen. Tech. Re p. PSW-GTR-146. 1993 
Table 2―Variance analyses of 5- and 6-year height of Douglas-fir in common-garden tests in Spain 

Plantation, height, Variance components1 and p values 

Seed sources, and 

source of variation All trees 15 tallest 10 tallest 5 tallest 

Northwest Spain 

La Hermida2 

5-yr ht, SE, cm 67.5, 3.52 82.0, 5.14 86.7, 4.90 98.6, 5.45 

Seed sources, no. 86 63 81 85 

Seed source, S 38.13 .000** 11.20 .001** 21.82 .000** 26.52 .000** 

Block, B 9.75 .―― 7.29 .000 6.89 .000 8.26 .000 

SB 51.94 .―― 31.34 .000 33.11 .000 37.06 .000 

Trees, T(SB) .―― 50.17 38.18 28.16 

mean square3 186.98 506.80 373.70 286.54 

Sierra del Eje2 

5-yr ht, SE, cm 38.1, 2.72 44.7, 3.69 50.4, 3.79 60.5, 4.23 

Seed sources, no. 87 56 80 87 

Seed source, S 11.62 .020* 5.55 .063 6.82 .037* 7.64 .046* 

Block, B 10.92 .―― 6.44 .000 6.73 .000 7.19 .000 

SB 77.46 .―― 36.88 .000 46.62 .000 58.52 .000 

Trees, T(SB) .―― 51.13 39.82 26.65 

mean square3 145.57 292.12 233.11 180.28 

Bande 

5-yr ht, SE, cm 89.2, 6.08 142.3, 13.32 152.9, 13.86 168.6, 14.55 

Seed sources, no. 22 22 22 22 

Seed source, S 62.9 .000** 46.65 .000** 48.72 .000** 51.34 .000** 

Block, B 10.8 .―― 16.79 .000 17.45 .000 18.18 .000 

SB 26.3 .―― 16.72 .000 17.75 .000 18.93 .000 

Trees, T(SB) .―― 19.84 16.08 11.55 

mean square3 221.81 599.75 505.48 383.37 

Castro Dozón 

5-yr ht, SE, cm 72.8, 4.14 99.5, 7.25 106.7, 8.07 117.8, 8.83 

Seed sources, no. 5 5 5 5 

Seed source, S 71.49 .001** 40.59 .006** 38.86 .013* 38.35 .034* 

Block, B 12.03 .―― 13.25 .000 14.79 .000 13.58 .000 

SB 16.48 .―― 14.20 .000 18.96 .000 29.12 .000 

Trees, T(SB) .―― 31.96 27.39 18.95 

mean square3 55.42 304.98 280.04 220.00 

Fragavella4 

5-yr ht, SE, cm 37.1, 2.69 59.7, 5.75 61.6, 5.83 73.4, 7.31 

Seed sources, no. 20 14 16 17 

Seed source, S 50.90 .000** 3.49 .299 25.03 .004** 21.34 .016* 

Block, B 9.17 .―― 12.23 .000 9.95 .000 13.25 .000 

SB 39.92 .―― 37.71 .000 33.01 .000 39.89 .000 

Trees, T(SB) .―― 46.57 32.01 25.52 

mean square3 77.37 305.50 267.58 257.30 

Regavella 

5-yr ht, SE, cm 42.9, 2.98 58.0, 5.43 60.6, 5.94 68.5, 6.71 

Seed sources, no. 21 16 19 20 

Seed source, S 20.11 .031* 13.24 .046* 19.11 .010** 21.67 .008** 

Block, B 19.45 .―― 13.61 .000 14.39 .000 15.92 .000 

SB 60.43 .―― 35.35 .000 36.21 .000 38.85 .000 

Trees, T(SB) .―― 37.80 30.29 23.57 

mean square3 72.04 209.37 194.57 176.00 

continues 

36 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
Table 2―Variance analyses of 5- and 6-year height of Douglas-fir in common-garden tests in Spain 

Plantation, height, Variance components1 and p values 

Seed sources, and 

source of variation All trees 15 tallest 10 tallest 5 tallest 

Sierra de Meira 

5-yr ht, SE, cm 53.5, 3.97 

Seed sources, no. 14 

Seed source, S 11.12 .334 

Block, B 7.88 .――

SB 81.00 .――

Trees, T(SB) .――

mean square3 187.27 

Gamalleira 

5-yr ht, SE, cm 103.2, 3.09 

Seed sources, no. 21 

Seed source, S 57.78 .000** 

Block, B 0.10 .――

SB 42.11 .――

Trees, T(SB) .――

mean square3 571.12 

Valdemadeiro 

5-yr ht, SE, cm 61.1, 1.68 

Seed sources, no. 19 

Seed source, S 74.84 .000** 

Block, B 3.77 .――

S13 21.38 .――

Trees, T(SB) .――

mean square3 36.79 

North central Spain 

Conforcal 

6-yr ht, SE, cm 183.2, 5.08 

Seed sources, no. 18 

Seed source, S 34.68 .000** 

Block, B 5.76 .――

SB 59.55 .――

Trees, T(SB) .――

mean square3 1525.3 

La Gallina 

6-yr ht, SE, cm 122.0, 13.87 

Seed sources, no. 12 

Seed source, S 50.65 .000** 

Block, B 32.06 .――

SB 17.29 .――

Trees, T(SB) .――

mean square3 297.89 

*, ** Significant at p <0.05, <0.01 

―― 64.4, 3.36 76.7, 4.10 

―― 11 12 

.―― .―― 5.75 .357 4.09 .422 

.―― .―― 0.00 .441 0.00 .671 

.―― .―― 36.99 .000 54.81 .000 

.―― 57.26 41.10 

.―― 352.39 294.06 

159.8, 5.23 169.8, 5.44 185.7, 5.89 

21 21 21 

40.75 .000** 39.72 .000** 36.64 .001** 

0.58 .000 0.57 .000 0.64 .004 

40.13 .000 42.86 .000 48.59 .000 

18.54 16.85 14.14 

596.87 555.49 476.59 

102.0, 3.09 109.5, 3.36 121 .2, 3.75 

19 19 19 

26.29 .000** 24.00 .002** 18.81 .027* 

2.66 .000 2.96 .000 3.14 .000 

23.23 .000 29.93 .000 43.09 .000 

47.82 43.11 34.97 

337.52 305.58 255.18 

―― 226.5, 5.78 250.3, 6.82 

―― 18 18 

.―― .―― 29.35 .000** 28.56 .000** 

.―― .―― 3.62 .000 4.98 .――

.―― .―― 26.76 .000 66.46 .――

.―― 40.27 .――

.―― 1943.2 3211.1 

164.6, 19.47 181.2, 20.31 196.1, 21.88 

11 11 12 

33.00 .000** 35.91 .000** 44.72 .000** 

23.87 .000 25.55 .000 25.04 .000 

11.45 .000 12.81 .000 11.22 .000 

31.68 25.73 19.01 

1434.4 1181.8 1038.3 

continues 

1 Variance components are expressed as a percentage of the total variance in analyses using the 

mean of all trees and the 15, 10, and 5 tallest in each plot, except the 2 and 1 tallest at Conforcal. 

See tables 2-3. 2 Includes P. flahaulti and P. macrolepis. See Appendix table 1. 3 Actual estimate of SB mean square using the mean of all trees in each plot, except the 1 tallest tree 

at Conforcal, and T(SB) mean square using the 15, 10, and 5 tallest trees in each plot, except the 2 

tallest at Conforcal. 

4 Includes P. flahaulti. See Appendix table 1. 

37 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
Table2―Variance analyses of 5- and 6-year height of Douglas-fir in common-garden tests in Spain 

Plantation, height, Variance components1 and p values 

Seed sources, and 

source of variation All trees 15 tallest 10 tallest 5 tallest

La Vecilla 

6-yr ht, SE, cm 96.2, 5.51 151.0, 8.34 168.6, 7.63 193.4, 6.80 

Seed sources, no. 9 9 9 9 

Seed source, S 49.58 .004** 35.88 .000** 38.78 .000** 45.96 .000** 

Block, B 9.73 .―― 6.03 .000 5.39 .000 3.83 .000 

SB 40.70 .―― 6.55 .000 8.34 .000 12.19 .000 

Trees, T(SB) .―― 51.54 47.48 38.12 

mean square3 260.56 1503.7 1211.1 875.16 

Salinas de Léniz 

5-yr ht, SE, cm 107.8, 12.91 155.0, 18.75 163.3, 19.90 178.0, 20.55 

Seed sources, no. 15 14 15 15 

Seed source, S 0.00 .857 0.00 .842 0.00 .868 0.00 .908 

Block, B 43.85 .―― 34.23 .000 36.55 .000 37.60 .000 

SB 56.15 .―― 47.17 .000 48.96 .000 51.55 .000 

Trees, T(SB) .―― 18.61 14.48 10.85 

mean square3 590.06 520.47 430.96 333.94 

Ataun 

5-yr ht, SE, cm 165.3, 3.48 230.9, 5.46 242.5, 6.36 258.9, 7.84 

Seed sources, no. 15 14 14 14 

Seed source, S 68.73 .000** 52.17 .000** 51.04 .000** 51.42 .000** 

Block, B 0.24 .―― 1.36 .000 2.59 .000 5.28 .000 

SB 31.03 .―― 22.94 .000 25.85 .000 27.34 .000 

Trees, T(SB) .―― 23.54 20.53 15.96 

mean square3 486.01 677.65 543.29 394.45 

Ochagavía 

5-yr ht, SE, cm 143.8, 2.38 206.8, 3.19 215.4, 3.01 227.6, 2.90 

Seed sources, no. 31 31 31 31 

Seed source, S 61.34 .000** 40.67 .000** 41.23 .000** 41.09 .000** 

Block, B 1.15 .―― 0.77 .000 0.56 .000 0.29 .000 

SB 37.51 .―― 33.89 .000 36.71 .000 41.61 .000 

Trees, T(SB) .―― 24.67 21.50 17.02 

mean square3 269.82 392.71 322.11 245.56 

*, ** Significant at p <0.05, <0.01 1 Variance components are expressed as a percentage of the total variance in analyses using the 

mean of all trees and the 15, 10, and 5 tallest in each plot, except the 2 and 1 tallest at Conforcal. 

See tables 2-3. 2 Includes P. flahaulti and P. macrolepis. See Appendix table 1. 3 Actual estimate of SB mean square using the mean of all trees in each plot, except the 1 tallest tree 

at Conforcal, and T(SB) mean square using the 15, 10, and 5 tallest trees in each plot, except the 2 

tallest at Conforcal. 

4 Includes P. flahaulti. See Appendix table 1. 

38 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
Table 3―Variance analyses of 5-year height of Douglas-fir in pairings of the 

principal common-garden tests in Spain 

Plantation pair, Variance components1 and p values 

Seed sources, and 

source of variation All trees 10 tallest 5 tallest 

La Hermida<>Sierra del Eje2 

Seed sources, no. 86 76 85 

Planting site, P 59.74 .002** 43.37 .004** 44.57 .004** 

Seed source, S 9.13 .000** 7.16 .000** 8.86 .000** 

Block, B(P) 3.88 .―― 3.92 .000 4.13 .000 

PS 3.90 .006** 3.31 .020* 2.96 .045* 

SB(P) 23.35 .―― 21.14 .000 24.65 .000 

Trees, T(PSB) .―― 21.10 14.82 

mean square3 166.92 301.12 231.64 

*, ** Significant at p <0.05, <0.01 1 Variance components are expressed as a percentage of the total variance in 

analyses using the mean of all trees in each plot and the 10 and 5 tallest in each 

plot. See tables 2-3. 2 Includes P. flahaulti and P. macrolepis. See Appendix table 1. 3 Actual estimate of SB(P) mean square using the mean of all trees in each plot and 

T(PSB) mean square using the 10 and 5 tallest in each plot. 

39 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
Table 4―Variance analyses of 5- and 6-year height of Douglas-fir in pairings of the 

principal and satellite common-garden tests in Spain 

Plantation pair, Variance components1 and p values 

Seed sources, and 

source of variation All trees 10\15 tallest 5\15 tallest 

La Hermida<>Bande 

Seed sources, no. 

Planting site, P 

Seed source, S 

Block, B(P) 

PS 

SB(P) 

mean square2 

La Hermida<>Fragavella3 

Seed sources, no. 

Planting site, P

Seed source, S

B(P) 

PS 

SB(P) 

mean square2 

La Hermida<>Regavella 

Seed sources, no 

Planting site, P 

Seed source, S 

B(P) 

PS 

SB(P) 

mean square2 

La Hermida<>Gamalleira 

Seed sources, no. 

Planting site, P 

Seed source, S 

B(P) 

PS 

SB(P) 

mean square2 

La Hermida<>Valdemadeiro 

Seed sources, no 

Planting site, P 

Seed source, S 

B(P) 

PS 

SB(P) 

mean square2 

40 

20 18 20 

34.30 .020* 58.37 .009** 40.28 .021* 

27.49 .000** 13.75 .000** 24.18 .000** 

7.78 .―― 8.37 .―― 9.53 .―― 11.19 .001** 8.13 .000** 10.68 .000** 

19.23 11.38 15.32 

187.82 415.07 450.21 

20 14 14 

62.85 .002** 48.14 .013* 65.27 .005** 

11.12 .000** 2.36 .218 1.27 .255 

4.18 .―― 8.46 .―― 6.21 .――

4.11 .056 0.00 .571 0.00 .535 

17.74 41.04 27.25 

120.64 339.20 377.29 

21 16 16 

49.87 .005** 46.56 .013* 62.29 .005** 

14.83 .000** 12.35 .000** 7.86 .000** 

5.18 .―― 8.00 .―― 6.21 .――

9.03 .005** 5.33 .108 2.90 .168 

21.09 27.76 20.74 

123.31 295.72 342.28 

19 18 19 

35.37 .002** 66.98 .000** 44.44 .000** 

22.60 .000** 6.21 .002** 18.55 .000** 

2.15 .―― 1.10 .―― 1.18 .――

13.19 .003** 3.78 .115 10.02 .011* 

26.70 21.92 25.80 

409.95 918.56 916.17 

15 15 15 

6.80 .084 17.31 .009** 0.00 .713 

29.04 .000** 21.83 .000** 24.38 .000** 

4.83 .―― 2.48 .―― 4.32 .――

12.60 .060 11.30 .077 12.14 .103 

46.73 47.10 59.16 

135.41 306.07 372.16 

continues 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
Table 4―Variance analyses of 5- and 6-year height of Douglas-fir in pairings of 

the principal and satellite common garden tests in Spain 

Plantation pair, Variance components1 and p values 

Seed sources, and 

source of variation All trees 10\15 tallest 5\1 5 tallest 

La Hermida<>La Gallina 

Seed sources, no. 10 9 9 

Planting site, P 54.15 .014* 56.21 .014* 45.56 .027* 

Seed source, S 18.86 .000** 17.23 .000** 22.76 .000** 

B(P) 9.73 .―― 10.43 .―― 12.94 .――

PS 8.47 .002** 7.38 .005** 7.88 .009** 

SB(P) 8.78 8.76 10.86 

mean square2 219.51 422.29 421.47 

La Hermida<>La Vecilla 

Seed sources, no. 8 8 8 

Planting site, P 9.46 .148 41.08 .016* 22.99 .058 

Seed source, S 33.04 .000** 24.94 .000* 30.07 .000** 

B(P) 12.82 .―― 8.01 .―― 11.71 .――

PS 0.00 .747 5.74 .116 5.35 .196 

SB(P) 44.67 20.23 29.88 

mean square2 329.60 495.23 606.89 

La Hermida<>Ataun 

Seed sources, no. 15 14 14 

Planting site, P 78.99 .000** 84.35 .000** 80.66 .000** 

Seed source, S 8.88 .000** 6.22 .000** 7.59 .000** 

B(P) 0.64 .―― 0.76 .―― 1.09 .――

PS 3.71 .010** 2.42 .025* 2.23 .069 

SB(P) 7.78 6.25 8.43 

mean square2 419.67 673.79 770.01 

La Hermida<>Ochagavía 

Seed sources, no. 31 30 31 

Planting site, P 80.00 .000** 85.61 .000** 81.69 .000** 

Seed source, S 7.83 .000** 5.13 .000** 6.34 .000** 

B(P) 0.77 .―― 0.69 .―― 0.88 .――

PS 3.16 .002** 1.75 .018* 2.26 .016* 

SB(P) 8.25 6.83 8.82 

mean square2 264.51 519.61 566.25 

*,* Significant at p <0.05, <0.01 1 Variance components are expressed as a percentage of the total variance in 

analyses using the mean of all trees in each plot and the means of the 10\15 and 

5\1 5 tallest in each plot. See tables 2-3. 2 Actual estimate of SB(P) mean square. 

3 Includes P. flahaulti. See Appendix table 1. 

41 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
Table 5―Variance analyses of 5- and 6-year height of Douglas-fir in pairings of the anchor and 

other satellite common-garden tests in Spain 

Plantation pair, Variance components1 and p values 

Seed sources, and 

source of variation All trees 15 tallest 10 tallest 5 tallest 

Bande<>Ochagavía 

Seed sources, no. 

Planting site, P 

Seed source, S 

B(P) 

PS 

SB(P) 

Trees, T(PSB)

mean square2 

Bande<>Gamalleira 

Seed sources, no. 

Planting site, P 

Seed source, S 

Block, B(P)

PS 

SB(P) 

Trees, T(PSB) 

mean square2 

Gamalleira<>Ochagavía 

Seed sources, no. 

Planting site, P 

Seed source, S 

B(P) 

PS 

SB(P) 

Trees, T(PSB)

mean square2 

La Gallina<>Ataun 

Seed sources, no. 

Planting site, P 

Seed source, S 

B(P) 

PS 

SB(P) 

Trees, T(PSB) 

mean square2 

42 

7 7 7 7 

53.09 .002** 36.79 .011* 34.65 .015* 30.47 .022* 

25.51 .000** 23.57 .000** 24.19 .000** 25.91 .000** 

2.83 .―― 5.58 .000 6.45 .000 7.29 .000 

3.30 .177 9.49 .030* 11.07 .022* 12.35 .025* 

15.27 .―― 14.50 .000 15.00 .000 17.14 .000 

.―― 10.08 8.65 6.83 

289.03 435.88 368.90 280.65 

8 8 8 8 

0.00 .795 0.00 .566 0.00 .474 0.00 .416 

44.38 .000** 24.82 .001** 25.50 .002** 26.79 .003** 

5.44 .―― 9.93 .000 10.37 .000 11.74 .000 

1.61 .391 4.79 .26 22.57 .35 10.00 .501 

48.58 .―― 38.93 .000 43.72 .000 49.46 .000 

.―― 21.53 17.84 12.02 

498.40 677.00 570.45 395.36 

9 9 9 9 

43.54 .006** 30.31 .007** 28.43 .008** 23.08 .016* 

11.75 .015* 11.47 .017* 12.24 .017* 11.75 .033* 

4.63 .―― 3.45 .000 3.51 .000 4.15 .000 

3.23 .297 0.00 .600 0.00 .675 0.00 .758 

36.84 .―― 36.16 .000 38.47 .000 44.75 .000 

.―― 18.61 17.35 16.26 

507.21 481.22 441.92 406.06 

5 4 4 4 

5.25 .176 6.51 .164 4.87 .211 3.38 .251 

60.38 .000** 47.04 .000** 49.50 .000** 51.96 .000** 

9.33 .―― 10.01 .000 11.79 .000 12.26 .000 

2.97 .277 5.18 .191 2.99 .282 0.35 .409 

22.06 .―― 17.19 .000 19.72 .000 22.90 .000 

.―― 14.08 11.14 9.14 

699.77 1150.7 886.38 716.29 

continues 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
Table 5―Variance analyses of 5- and 6-year height of Douglas-fir in pairings of the anchor and 

other satellite common-garden tests in Spain 

Plantation pair, Variance components and p values 

Seed sources, and 

source of variation All trees 15 tallest 10 tallest 5 tallest 

La Gallina<>Ochagavía 

Seed sources, no. 7 6 6 7 

Planting site, P 3.82 .239 16.25 .080 10.27 .146 3.49 .260 

Seed source, S 51.97 .000** 23.66 .000** 25.84 .000** 43.10 .000** 

B(P) 12.61 .―― 10.74 .000 13.41 .000 14.13 .000 

PS 14.93 .010** 14.49 .011 * 15.64 .016* 11.16 .022* 

SB(P) 16.68 .―― 12.82 .000 15.53 .000 13.03 .000 

Trees, T(PSB) .―― 22.05 19.31 15.10 

mean square2 311.58 1090.0 868.12 748.75 

Ataun<>Ochagavía 

Seed sources, no. 14 13 13 13 

Planting site, P 15.13 .000** 7.72 .014* 10.01 .019* 13.45 .029* 

Seed source, S 54.78 .000** 37.85 .000** 35.29 .000** 32.24 .000** 

B(P) 0.09 .―― 1.32 .000 2.05 .000 3.80 .000 

PS 4.76 .126 5.62 .115 6.08 .118 6.96 .109 

SB(P) 25.23 .―― 25.38 .000 27.62 .000 29.28 .000 

Trees, T(PSB) .―― 22.12 18.94 14.27 

mean square2 378.61 555.45 441.30 318.32 

*,** Significant at p <0.05, <0.01 1 Variance components are expressed as a percentage of the total variance in analyses using the 

mean of all trees in each plot and the 15, 10, and 5 tallest in each plot. See tables 2-3. 2 Actual estimate of SB(P) mean square using the mean of all trees in each plot and T(PSB) mean 

square using the 15, 10, and 5 tallest in each plot. 

43 

USDA Forest Service Gen. Tech. Rep. PSW-GTR-146. 1993 
The Forest Service, U.S. Department of Agriculture, is responsible for Federal leadership in forestry. 

It carries out this role through four main activities: 

• Protection and management of resources on 191 million acres of National Forest System lands 

• Cooperation with State and local governments, forest industries, and private landowners to help 

protect and manage non-Federal forest and associated range and watershed lands 

• Participation with other agencies in human resource and community assistance programs to 

improve living conditions in rural areas 

• Research on all aspects of forestry, rangeland management, and forest resources utilization. 

The Pacific Southwest Research Station 

• Represents the research branch of the Forest Service in California, Hawaii, American Samoa, 

and the western Pacific. 

Persons of any race, color, national origin, sex, age, religion, or 

with any handicapping conditions are welcome to use and enjoy 

all facilities, programs, and services of the U.S. Department of 

Agriculture. Discrimination in any form is strictly against agency 

policy, and should be reported to the Secretary of Agriculture, 

Washington, DC 20250. 
Forest Service Screening Douglas-fir for Rapid Early Growth in Common-Garden 

Pacific Southwest Research Station General Technical Report PSW-GTR-146