united .-a . .,- Practical Guidelines for 

mm"M 5r .C oqir - kp; + h(iucing Longleaf Pine 

~~ -.-* - Seedlings in Containers 
'lhe Authors: 

.James P. Harnett 15 Ch~ei SII\ lcultur~\t and John M. McGilvray I\ 

Blolog~cal Science Technlc~an. Southern Re\earch Stat~on. U S Department 

of Agr~cultt~re, Forc\t Serv~ce, Alexandna Forestry Center. P~nev~lle. I,A

7 1 160 

The use of trade or firm names in this publication is for reader information 

and does not imply endorsenlent by the U.S. Department of Agriculture of 

any product or service. 

This publication reports research involving pesticides. It does not contain 

recommendations for their use, nor does it imply that the uses discussed 

here have been registered. All uses of pesticides must be registered by 

appropriate State andlor Federal agencies before they can be recommended. 

CAUTION: Pesticides can be injurious to hurnans, domestic animals, 

desirable plants, and fish or other wildlife-if they are not handled or 

applied properly. Use all herbicides selectively and carefully. Follow 

reconimended practices for the disposal of surplus pesticides and their 

containers. 

August 1997 

Southern Research Station 

P.O. Box 2680 

Asheville, NC 28802 
Contents 

Page 

... Preface ........................................... 111 

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

... Fac~l~t~es .......................................... 4 

Structures ....................................... 4 

Protective Coverings ............................... 4 

Watering Systems ................................. 6 

Preparation of Recolnmendcd Materials .................. 7 

Container Selection ................................ 7 

Media Preparation ................................ 10 

Selecting media ................................ 10 

Mixing media .................................. 11 

Amending media ................................ 12 

Container Filling .................................. 13 

Seed Preparation .................................. 14 

Selecting seeds ................................. 14 

Treating seeds .................................. 15 

Cultural Practices ................................... 16 

GrowingSchedule ................................ 16 

Preparation Phase ................................. 16 

Sowingseeds .................................. 16 

Covering seeds ................................. I8 

Germination Phase ................................ 19 

Juvenile Growth Phase ............................. 20 

Exponential Growth Phase .......................... 22 

Hardening Phase .................................. 23 

Extraction. Storage. and Transport ...................... 24 

Planting .......................................... 25 

Conclusions ....................................... 27 

Literature Cited .................................... 28 

Preface 

These guidelines are based on the current knowledge on container tree 

nursery management for longleaf pine. Recommendations are made using 

the best information available at the time and are, therefore, subject to 

revision as more knowledge becomes available. There is no substitute for 

individual experience, and recommended cultural practices should be 

tested and developed by local growers before implementing on an 

operational scale. Nursery managers will need to adapt these principles 

and procedures to their own nursery conditions. 

The use of trade or firm names in this publication is for reader information 

and does not imply endorsement by the U.S. Department of Agriculture of 

any product or service. 

This publication reports research involving pesticides. It does not contain 

recommendations for their use, nor does it imply that the uses discussed 

here have been registered. All uses of pesticides must be registered by 

appropriate State andlor Federal agencies before they can be 

recommended. 

CAUTION: Pesticides can be injurious to humans, domestic animals, 

desirable plants, and fish or other wildlife-if they are not handled or 

applied properly. Use all pesticides selectively and carefully. Follow 

recommended practices for the disposal of surplus pesticides and 

pesticide containers. 

Practical Guidelines for Producing 

Longleaf Pine Seedlings in Containers 

James P. Barnett and John M. McGilvray 

Abstract 

Longleaf pine, although widely distributed in the presettlement forests of the southern Coastal 

Plain, now occupies less than 10 percent of its original range. It is a highly desirable species 

because it resists tire, insects, and disease and produces excellent quality solid-wood 

products. Regeneration of the species either by natural methods or by planting of bare-root 

nursery stock has been difticult, and renewed interest in it has resulted in evaluation of new 

approaches to seedling establishment. Using container stock has greatly improved the 

success of longleaf pine establishment. Practical guidelines are presented that will Iielp 

nursery personnel consistently produce good container stock that will survive well and initiate 

early height growth. 

Keywords: Nursery practices, Pinuspalustris Mill.. planting techniques, seed germination 

Introduction 

Of all the southern pines, many consider longleaf pine (Pinus palustris 

Mill.) the most valuable in terms of wood-product quality, aesthetics, and 

resistance to fire, insects, and disease. In the presettlement era, an 

estimated 60 million acres of the longleaf pine ecosystem extended from 

east Texas through the lower Coastal Plain to Virginia (fig. 1). Heavily 

harvested in the late 1800's and early 1 900's, few longleaf stands survived. 

By 1935, only about 6 percent of old-growth longleaf pine remained in 

Louisiana (Whlenburg 1946). Few seed trees endured these harvests, and 

much of the area was converted to other species or abandoned to grassland 

(fig. 2). Today, natural regeneration is only feasible on a small portion of 

the area in the longleaf pine type. 

Because longleaf pine is considered a desirable tree, why have we failed to 

regenerate more of the longleaf sites'? The answers to this question are 

related to the unique botanical characteristics of the species: (1) low and 
F~I-V~~ofhgkafpine~marwoods,L&~t~ddthogtfoa

the lower Coastal Plain Wow barvest in la* 1Ws and carly 19011's. 
infrequent seed production, (2) a seedling "grass" stage characterized by 

delayed stem elongation, (3) poor storability of bare-root nursery stock that 

results in low survival, and (4) seedling intolerance to shade conditions 

caused by competition. 

The knowledge and technology to reestablish longleaf pine by planting 

bare-root nursery stock have improved significantly in the last decade. The 

components of successful regeneration include: (I) well-prepared, 

competition-free sites; (2) healthy, top-quality, fresh planting stock; 

(3) meticulous care of stock from lifting to planting; (4) precision planting; 

and (5) proper post-planting care. All these elements are essential to 

successful planting of bare-root stock. Because controlling all five 

elements is difficult in many cases, planting success with bare-root 

longleaf pine stock remains elusive. These same components apply to 

container stock, where regeneration success is markedly better. Therefore, 

many silviculturists now prefer to plant container longleaf pine seedlings. 

Numerous studies have demonstrated that under adverse planting 

conditions. such as poor sites, conditions of moisture stress, and out-ofseason planting, container seedlings survive and grow better than bare-root 

stock (Barnett and McGilvray 1993). These improved survival and growth 

rates are generally attributed to root systems that remain intact during 

lifting while roots of bare-root plants are severely damaged. Thus, 

container seedlings experience a significantly shorter period of transplant 

shock or adjustment than bare-root seedlings. 

Successful production of container seedlings requires thoughtful planning 

before sowing and daily attention while growing (Landis and others 1994). 

The goal should be to produce longleaf pine seedlings with root-collar 

diameters of at least one-fourth inch, an abundant presence of secondary 

needles, and a healthy root system with obvious mycorrhizal development. 

This paper provides basic information that will help nursery managers 

produce good quality longleaf pine container stock. 
Facilities 

Structures for growing container seedlings in the South may vary from the 

simple to the complex (figs. 3A, 3B, 3C). Longleaf pines can be grown in 

the open without a structure or, at most, in semicontrolled greenhouses. 

Most research shows that Iongleaf pine seedlings grown in full sunlight are 

superior to those grown in shaded st~~cm (Bmtt 1989). 

Pmtectfve Covering 

Some protection from hard rainfall is encouraged during germination 

because large raindrops can wash seeds and some of the medium from the 

container, It can also cause the newly emerging radicle to become 

disoriented, res Jting in an abnormal cmk. A 30-percent shade cloth over 

a simple framework will greatly reduce this hazard. Raindrops, even 

during a downpour, are reduced to a fine mist under the shade cloth. The 

shade cloth should be removed as soon as germination is complete. If 

crops are overwintered and greenhouse protection is unavailable, 

polyethylene or other protective coverings may be used to protect seedlings 

hm strong desiccating winds and ternperam klow 25 OF. 

Figure Haoctnres fw mhg w0taim-r geedlings my vary from (A) opea benchas to (B) 

simple shade houses, to (C) ehhmte glass pdmuses. 

watering Sgstems 

An adequate water system is essential for growing conhiner stock. The 

system should supply an even distribution of water and provide nubients 

and fungicides as @bed wdis and others 1989). A simpIe, stake 

type with a sprinkler head is usually adequate (fig. 4). 

Pigwe 4-A simple, &type prinkkt head typical of thomz ud for optn irrigation 

sitdorm. 
Pmparation of 

Recommended MateContainer Selection 

One of the first and most important 

decisions involves selecting tbe type of 

container to use (Landis and others 

1990b). Experience has shown that a 

"plug"-type container, whem the root 

system is extracted with tbe medium 

intact More planting, should be used 

(fig. 5). The id4 individual container 

cavity should have a volume of about 6 

cubic inches, a minimum depth of 4.5 

inches, and a seedling density of 40 per 

square foot. Smaller containers that 

improve the eronomics of mtainer 

production can b~ used if cultutal 

practices are carefully controlled. Only 

one type and size of conminer should be 

used within a growing am because 

cultural techniques, especially irrigation. 

differ among areas and growth phases. If 

container types are mixed, each type or 

size should be kept under separate 

watering systems. Examples of types or ngurt -taf piat &plugm dling 

containers are Iisted below: txtractGd fmm a Multipot contahcc 

Container types 

RL Stubbies 

StymbIock 6 

Styd1wk 8 

Multipt 31% 

Multipot 4/96 

Multipot 267 

mo v-93 
Excellent quality seedlings can be produced in these, or similar containers, 

although some have properties more favorable to a particular species. 

nursery operation, or outplanting site. 

RL Stubbies are probably the best containers for growing small 

quantities, such as progeny tests, because empty individual cavities or 

cells can tx removed and remaining full cells can be reorganid (fig. 

6A). The cells extend 1.0 inch above the top of the tray that holds them 

together, and media falls between the cells when they are being filled. 

The excess media should be removed to allow gd air circulation 

between seedlings, a prm% that adds time to the mg operation. 

Care must also be used when handling trays, because individual cdls 

may fall from the tray if it is lipped 

StyrobIocks are relatively inexpensive, but they are easily damaged 

during handing. Moreover, if seedlings are held for extended periods, 

roots will begin to penetrate the stydoam, making plug extraction 

dtfficult (fig. 6B). 

Figure 6-&tainen frequently used to prwuce lmglear plne mg. W~UOC {A) RL 

Stubbits. (8) Srymblocks. and (C) Multipws. 
Multipots are suitable for large-scale operations, because they are 

durable and easy to handIe (fig. 6C). However, they are relatively 

expensive and lack ridges or other supports on the bottom that allow air 

circulation needed for mt pruning. Air movement beneath the 

containers must be provided. 
Media Pmparation 

!3ek&n# media-Materials such as peat, cornposted organic materid, 

sawdust, bark vermiculite, topsoil, and perlite have been evaluated for use 

as container-growing media (hdi and others 1Mb). A I-to-1 mixhue 

of sphagnum pat moss and medium-- (a) horticultural vermiculite 

has been a consistently gocd @uct (fig. 7). This mixture has physical, 

chemical, and biological properties that muIt in goad water-hoIding 

capacity and aeration and high cati~n exchange capacity. The quality of 

the peat and vermiculite varies among sources. The peat should be 

screened (free of large sticks. etc.). and the vermiculite a coa pde. 

Fine p&s of vermiculite result in a medium that compacts in the 

container and, thus, reduces aeration and restricts drainage. 

Good quality seedlings can be grown using other blends of media, especially 

those that include perlite. A small propwtion of perlite can improve 

drainage and aeration in wetter spring months when lower transpiration 

occurs. The grower must recognize that changing the blend of the medie can 

drastically change culhu;ll practices such as irrigation and fertilization. 

southern pine container stmk. 
The nursery manager may purchase a commercial medium or blend it at 

the nursery. Many commercial Wends are designed for horticultural: use 

and the pH is too high {about 6.0) for conifer use. If commercial products 

are used, the grower should specify the components and the pH of the 

&a. The pH should be adjusted to about 4.5 to 5.0. When higber pH 

water is used, the pH of the media increases to the optimum of 5,0 to 5.5. 

This level dso restricts pathogen development. 

Mixing mdh-If la~ge amounts of media are needed, on-site blending is 

encouraged because the chance of crushing or wrnpacting the vermiculite 

particles is reduced Such crushing fquenrly occurs during bagging, 

stacking, and transporting, Although blending can be done with hand tools 

or equipment such as concrete mixers. equipment specifidly designed for 

blending is mommended for lqe operations (fig. 8). This blending 

equipment is mommended for three imptant reapom. First, it mixes the 

media th~~~]ughly in a short amount of time. (To avoid crushing the 

vermiculite, blending time should not exceed 2 minutes.) Second, it 

facilitates incorpmtion of amendments, such as lime nmdd for pH 

djustment. VIM, ir pllows water to be added during mixing. Adding 

water reduces dust ad moistens tbe medium for better filling of 

containers. The medium should hold its form without dripping water when 

squeezed in the hand. If tm wet, the medium will become too compacted 

during the blending and filling process. If tw dry, it wilI not compact 

properly and will be too pornus, making irrigation difficult. 

Figure 8-A lldlmbd blendcr 

is recommended for larger 

commercial @ens whue 

msik mixing of media is &sired. 
Amending media-Although adding a surfactant or wetting agent would 

increase the t~niformity and rate at which moisture spreads through 

hydrophobic peat moss. many of these products reduce germination of 

southern pine seeds when added at their rccom~nended rates (Barnett 

1977). Adding surfactants in the blending process is not recommended 

without preliminary evaluation. 

Grower\ may add lime to the medium to adju\t pH to the recommended 

level\ of 5.0 to 5.5. The amount of lime added depends on the initial pH 

of the media (Landi4 and other\ 1990b). 

Normally, water-soluble fertilizers are supplied through the irrigation 

system. However, because longleaf pine seedlings have little stem 

elongation, incorporating a slow-release fertilizer, such as Osmocote 18-6- 

12 NPK. into the media can be very helpful, especially for an 

inexperienced grower (Landis and others 1989). Thc recommended rate 

for Osmocote 18-6- 12 is 6 to 10 pounds per cubic yard of media. Some 

growers use abotrt half the recommended rate to maintain more flexibility 

in fertilization. This treatment supplies most of the NPK needed, but 

additional nutrients will be necessary. Using slow-release fertilizers is 

particularly valuable when frequent rains leach water-soluble nutrients and 

frequent irrigation is infeasible. lncorporating slow-release fertilizers will 

also reduce the time spent applying nutrients through the irrigation system. 

Fungus gnats (Brlrr!\sirr spp.) are small, dark, mosquito-like insects that 

can damage roots and spread fungi and disease from one container to 

another (James and others 1995). The larvae are small and maggot-like 

and thrive on organic matter in high-moisture-content growing media. 

lising a well-drained medium and allowing it to dry between irrigation 

impedes fungus gnat development. However, some nursery managers 

incorporate Pratt-Oxamyl 10-percent granular insecticide into the medium 

at 2 to 3 ounces per cubic yard to control fungus gnats. Nursery personnel 

should wear gloves and respirators when mixing this material into the 

media. 

Althot~gh seedlings are naturally inoculated with ectomycorrhizae by 

wind-borne spores, inoculation with a specific niycorrhizal fungus such as 

Pisolit~ls tir7ctori~l.s (Pt) is feasible and rnay be desired by some growers 

(Landis and others i990a). Inoculation can be accomplished by 
incorporating specially produced vegetative mycelium into the growing 

medium. The high cost and limited availability of this vegetative 

mycelium usually makes this option prohibitive. The most practical 

approach is to inoculate with a spore suspension of R. Pisolitus tinctoritis 

spores can be obtained from local-source fruiting bodies or from a 

reputable commercial: source. Inoculating with a water suspension of 

spores, the dosage rate should be 5 grams of double-sifted spores per 3 

gallons of water per 10,000 seedlings. The spore suspension can Ix 

applied to the medium surface after seed germination using a diaphragm 

type backpack sprayer. A mycorrhizae specialist should be consdted 

about the specific techniques and methds associated with the collection, 

extraction, storage, and application of Pt spores. 

Container Filling 

During container filling, either by band or mechanical equipment (fig. 9), the 

mdiurn should be slightly packed by vibrating or bouncing. The amount 

needed to fill containen should indude an additional 20 pemt to allow for 

compaction. Ebr example, a 6-cubic-inch container cavity will need 7.2 

cubic inches of medium for propw filling. The containers should be filled 

Egwe GMccttanical equipment is needed in large operations to fill containers with growing 

medium. 
mqletely and the excess shouId be brushed off, leaving the medium 

approximately one-half inch below the top of the containers. This 

depression keeps the seed in place and faciIitates watering. The depression 

will become deeper as irrigation and rainfall continue to pack the medium. 

Sekhg @&-Highquality seeds should be used in container nurseries. 

Seeds should have a minimum viability of 75 percent (fig. 10). Longleaf 

pine seed collection, processing, storage, and treatment requires exceptionaI 

cm to maintain quality equal to that of other well-processed souhem pine 

seeds (Barnett and Pesacreta 1993). Although stratification of longleaf 

seeds will increase speed of germindon by I to 2 days, it may reduce total 

gemination and is not recommeaded without pmliminary evaluations. 

Pigum I&Im@d pine seeds m large, thii coabod, and msitive to damage thing 

dldm, mhg, md mlagc. V - 
Treating seeds-Longleaf seed coats commonly have significant 

populations of pathogenic fungi that may cause damping-off of 

germinants. If seeds have low viability or vigor, treating them with 

hydrogen peroxide or a fungicide may minimize disease losses. Soaking 

seeds in a 30-percent peroxide solution for 30 to 60 minutes and rinsing 

thoroughly in water removes most seed-coat pathogens and generally 

improves germination of low-viability lots (Barnett 1976). 

Personnel at the North Carolina Claridge State Nursery routinely use a 

hydrogen peroxide treatment on their longleaf pine seeds. They soak 20 to 

25 pounds of seeds in special nylon bags. After soaking for 55 minutes in a 

30-percent hydrogen peroxide solution at a temperature of 75 OF or less, the 

bags are drained and drenched in three separate containers of clean water. 

The seeds are then removed from the bags and allowed to surface dry. 

A more practical but less effective alternative involves lightly coating or 

drenching seeds with a fungicide, such as thiram or benomyl, just before 

sowing. A benomyl soak prevents disease development from seed-coat 

organisms of longleaf pine. A 3- to 5-minute soak (2 tablespoons per 

gallon of water) is used at some nurseries. Germination is typically 

improved by about 5 percentage points. However, this use of benomyl is 

not currently registered. 
Cultural Practices 

Growing Schedule 

The best growing schedule, both biologically and economically, for longleaf 

pine is to sow seeds in the spring, grow the seedlings through the summer, 

harden the seedlings naturally in the fall, and outplant them in late fall or 

early winter (Brissette and others 1991). This schedule eliminates the need 

for an elaborate greenhouse structure, provides full sun for optimal growth, 

and achieves natural hardening. The optimum dates in the following 

growing schedule for longleaf pine may vary by location of the nursery. 

Production phase 

Preparation 

Germination 

Juvenile growth 

Exponential growth 

Hardening 

Aooroximate dates 

April to mid-May 

May 

June 

July to mid-September 

Mid-September to shipping 

Preparation Phase 

This phase includes the activities of mixing media, filling containers, and 

sowing seeds. These three distinct procedures make up one operation. 

Batches of freshly blended growing medium should be used to till 

containers. Filled containers should be seeded immediately and placed 

under an irrigation system. Completing these activities sequentially keeps 

the medium moist in the containers and makes rewetting unnecessary. 

Sowing seeds-Because all cells, with or without seedlings, cost the same 

to carry through a growing cycle, vigorous seedlings should be grown in as 

many cells as possible. Seed-sowing strategies shoilld be based on current 

germination test results. If the viability of the seedlot used is in the 70 to 

80 percent range (typical for most lots of longleaf seeds), two seeds per 

cavity should be sown, then thinned to one seedling before the seed coats 

are shed. Regardless of the sowing strategy, oversowing and thinning is 

preferred to transplanting germinants (Pawuk 1982). 

Situations may arise where sowing of one seed per cavity is the best 

option, even when seed quality is low. One such situation is an inadequate 

seed supply, a frequent occurrence in longleaf pine. Another possible 
situation occurs when the labor fbe is imkquak for thinning or 

transplanting. However, economic consi~m of canying empty cells 

must be evaluated against the cost of thinning. 

The scale of operation dmnniw whether the seeds are sown by band, by 

simpIe templates (fig. 1 1A) or by more elate seeding machines (fig. 

1113). When mdmicaI sowers are used, the containers should be 

(B) by more elahate vacuum ding machines. 
visually checked after sowing to ensure that the prescribed seediag rate has 

been met. In some instmm, hand seeding may be needed to complete the 

opemtion. 

Covering -After tilling and seeding the containers. most growers 

cover the seeds with a light layer of m4a or vermiculite. Vermiculite 

may be the better choice, because it allows more light penetration to the 

seed. This covering improves the moishve relationships around the seeds 

and, thus, improves and hastens germination. Seeds should tK covered 

with no more than one-eighth inch of material. hep covering slows 

germination and increases the chance of damping-off and other disease 

problem (Barnett 1988). 

?he need to cover seeds varies by the type of watering system used. 

Germination is usuaIly most complete and rapid when seeds remain 

uncovered and receive water by a misting system (Brissette and others 

1991). If sea& am watd less frequently, a light seed covering facilitates 

gemination by mtllchhg that retains wt~r near he seeds (fig. 12). 

Fip 1-ed wveriag equipment can be added to the end of the seeding production line 

to provide a covering that will enham sxd gemination. 
Germination Phase 

Controlling temperature and moisture is critical during the germination 

phase. Longleaf pine seeds germinate better at cooler temperatures than 

other southern pine species, because they are ecologically adapted to fall 

germination (Wahlenburg 1946). Day and night germination temperatures 

should be near 70 OF with a permissible range of 60 to 80 OF. Therefore, 

crops should be started in April or early May when temperatures are 

usually near this range. 

Containers must be watered frequently to keep the surface of the medium 

moist. The moisture content of the medium near the surface should remain 

near field capacity. However, care should be taken to avoid overwatering, 

which can lower germination and promote disease problems. In a typical 

watering schedule, seeds would be misted 30 to 40 seconds every 30 

minutes. Cycles vary among different types of irrigation systems. When 

germination is complete, frequent misting should be stopped, any shade 

cloth removed, and less frequent watering begun. 

Fungicide applications should begin as soon as feasible to reduce dampingoff of germinants and to inhibit pathogenic fungi development. The 

following fungicide, rate, and application method works well: 

Fungicide-benomyl50WP 

Rate-l rounded teaspoon per gallon of water 

Method-apply as a thorough drench 

Time-apply at biweekly intervals until October I 

Heavier rates of benomyl are not detrimental to seedling growth; therefore, 

more frequent applications are much better than applying too little. If 

inoculation with a spore suspension of Pt is planned, using benomyl is 

appropriate because it does not adversely affect Pt development. In fact, 

most studies show that it promotes Pt development (Pawuk and Bamett 

1981). 
Juvenile Growth Pbase 

Because iongleaf pine seedlings are sensitive to shade, they shouid be grown 

and hardened in full sunlight (Barnett 1989). During the first few weeks after 

gemination, top growth is minimal, but mt growth is extensive. llhnhg or 

hawplanting should be completed early in this period. Although sot 

generally recommended. needed transplanting must be done before radicle 

elongation exceeds about 2 inches. A broken radicle slows seedliig 

development and mult. in smaller seedlings that do not compete well with 

uninjud seedlings (Pawuk 1982). !3eedhgs should be thinned before mt 

branching begins and preferably &fore sd coats are dropped (fig. 13). 

If dow-release fertilizers are not used, fertilization of seedlings should 

begin as soon as possible after gemination and the first fungicide 

application. The following fertilization program has pduced quality 

longleaf pine seedlings: 

Fertilizer-Peters' 15- 16- 17 NPK Peat-Lite Special or equivalent 

Rate-350 plm (based on nitrogen only) 

Time-Apply as needed 

Method-Apply through the watering system 
The timing of fertilization depends on seedling development. Weekly 

application will result in maximum development of seedling diameter 

growth, but the timing of applications will vary with weather conditions. 

Lower frequencies of application reduce or eliminate the need to clip 

longleaf pine needles. This program can also be used to supplement slowrelease fertilizers. 

Seedlings should be watered thoroughly and the medium surface allowed 

to dry between waterings. Early morning irrigation is preferred, because 

the seedlings will dry before evening, reducing fungal growth. During 

irrigation, enough water should be applied to leach the cavities. Because 

the outer edges of rows or benches will dry faster than those toward the 

center, they will need additional watering (usually by hand). Water 

management is critical during this phase and requires daily observation. 

Ilur~ng the latter part of the germmatton or juvenlle phases, weed growth 

in the containers may become a problem Weed seed may be ~ncorporated 

In some grades of peat, borne by the wlnd, or spread through the water 

system if the water source 15 a pond or rlver If weeds are spread 

throughout the crop, a herbtc~de may be appl~ed GOAL I 6E 

(oxyfluorfen) 1s a select~ve, pre- and post-emergent herblclde that controls 

a broad spectrum of grasses and broadleaf weeds In con~fer seedbeds and 

container stock However, because newly germ~nated longleaf plne seeds 

are sensltlve to herb~clde damage, the application rate should be reduced to 

prevent damage Tests have shown that applylng 12 mllllliters of GOAL, 

1 6t: per gallon of water over 800 square feet does not result in damage 

Th~s reduced rate may requlrc \ubsequent appllcations (at weekly 

~ntervals) to obta~n complete weed control 

The crop must be carefully observed for other pest problems Insect 

problem\ [nay lncludc cutworms, ftingus gnats, and ants Apply~ng 

di:r/lnon at labeled rates w~ll control most of these pe\t\ D~seases may 

occur, \uch il\ rhi/o~toni;~, and a pest control spec~al~st should be consulted 

for treatment recommcndat~on\ 
Exponential Growth Phe 

The rapid growth during this phase is exhibited primarily by needle 

elongation. The initiation and length of the exponential growth phase is 

determined by both needle and stem development. Control of moisture is 

not as critical as during the previous growth phases. However, the 

seedlings must be monitored closely for signs of stress due to disease, 

nutrient deficiencies, or insuficient water. 

Fertilization as outlined for the juvenile phase should continue unless 

observations indicate a need for change such as more frequent 

applications. If growth remains slow w nitrogen deficiency is observed. a 

few applications of Peters' 20- 10-20PL NPK will usually correct the 

problem, If higher fertiliir rates are used, especially with the nitmbrich 

20- 10-2OPL NPK formulation, the fertilizer should be washed off the 

foliage to prevent possible burning. 

The rate of fertilization will determine whether clipping the longleaf pine 

needles is necessary. When the needles begin to lie over surrounding 

seedlings, problems in uniform growth and in pathogen development 

occur, and clipping or mowing is recommended (fig. 14). Care should be 

lodging. 
taken to clip only enough of the needles to reduce the problem, because 

excessive pruning will reduce growth. The needles should not be clipped 

to less than 6 inches, and all clippings should be removed to minimize 

fungal development. More than one clipping or mowing may be required 

during a growing cycle. 

As the seedlings become large in the latter stage of this phase, they will 

use more water. This increased usage combined with the normally hot, dry 

weather will result in the need for more frequent and heavier periods of 

irrigation. Irrigation should thoroughly leach the containers. 

Hardening Phase 

Hardening should start when stem diameters are near the desired size or 

when day lengths and temperatures restrict growth. The seedlings should 

be stressed by reducing moisture availability. The media should be 

allowed to dry to near the wilting point between waterings. No nutrients 

need to be applied. Just before shipping, the root plug should be brought 

to field capacity. 
Extraction, Storage, and +Ikansport 

The grower may extract seedlings from the containers at the nursery or 

ship the containers with seedlings and extract them in the field. Extracting 

seedlings at the nursery reduces the bulk for shipping and limits the loss 

and damage of costly containers that are reused to reduce production costs. 

During the extraction process, poorly developed seedlings can be discarded 

and the containers recycled. Seedlings should be placed in cardboard 

bxes for storage and shipment. Properly hardened, container longleaf 

seedlings can be exh-acted, boxed, and stored under refrigeration similar to 

bare-root stock. 

They can also be held in containers in the nursery until ready for shipment. 

Seedling boxes should be designed for proper stacking strength. and racks 

may be needed in the trucks or trailers used for transportation. These 

boxes can also be used to facilitate distribution in the field (fig. 15). 

good mans to distribute the aingfi lo planters in tht field 
Planting 

Despite their bulk and weight, container seedlings are easy to plant by 

hand or machine because their root systems are uniformly shaped. The 

control of planting depth is critical for longleaf pine. The bud should be at 

about the soil surface (fig. 16). Dibbles shaped like the root plug work 

well because the problem of planting too deep can be avoided (fig. 17A). 

Most mechanical planters designed for bare-root seedlings can be adapted 

for container stock with only minor modifications (fig. 17B). 

Properly Machine Planted 

Longleaf Pine Seedling 

Settled Soil 

I Berm Created 

/ by Machine 

I.IF~I~-c I0 (‘on11-oiling planting tlcplh I\ ilnporl;rnl lol- longlcal' pint \cccllingh 
Figure 17-PIantlag container *k GUI bt accomplished (A) by dibbks shapsd like thc 

rwl pIug. w 

(B) with rnCEWal p1anbx-s 

designed for planting bare-mot stack. 

Because survival of container 

dings is very good, the 

planting season can be extended 

(Bamett and Brhme 1986). 

Planting longleaf pine dings in 

the fdI, as soon as adequate soil 

moisture is obtained. results in 

goad field performance. Rwt 

systems become well established 

during the winter months and as a 

nsult, the length of the gms stage 

can be shortened. 
Conclusions 

Reforestation success for longleaf pine can be improved by planting 

seedlings produced in containers.. Container stock survives better than bare 

mt stock w typical longleaf pine sites and the length of time seedings 

stay in the grass stage is reduced Thus, planting of container stock 

generally improves the reforestation success of longleaf pine seedlings (fig. 

18). However, using container stock does not eliminate the critical need for 

controlling competition during the first growing season to ensure that 

seedlings begin height growth during the second year after planting. 
Literature Cited 

Rarnett, J.P.; McGilvray, J.M. 1993. Performance of container and hareroot loblolly pine 

seedlings on bottomlands in South Carolina. Southern Journal of Applied Forestry. 17: 80-83. 

Barnett, J.P.; Pesacreta, T.C. 1993. Handling longleaf pine seeds for optirnal nursery 

performance. Southern Journal of Applied Forestry. 17: 180- 187. 

Rarnett, James P. 1976. Sterilizing southern pine seeds with hydrogen peroxide. Tree 

Planters' Notes. 27(3): 17- 19. 

Barnett, .James P. 1977. Effects of soil wetting agent concentration of southern pine seed 

germination. Southern Journal of Applied Forestry. I : 14- 15. 

Rarnett, James P. 1988. Covering affects container germination of southern pine seeds. Tree 

Planters' Notes. 29(2): 13- 15. 

Rarnett, James P. 1989. Shading reduces growth of longleaf and loblolly pine seedlings in 

containers. Tree Planters' Notes. 40( 1): 23-26. 

Rarnett, James P.; Brissette, John C. 1986. Producing southern pine seedlings in containers 

Gen. Tech. Keu. SO-59. New Orleans, LA: U.S. Department of Agriculture, Forest Service, 

Southern Forcct Experiment Station. 7 I p. 

Rrissette, John C.; Barnett, James P.; Landis, Thomas D. 1991. Container seedlings. In: 

Duryea, Mary L.; Dougherty, Phillip M., eds. Forest regeneration manual. Dorcrecht, The 

Netherlands; Boston; London: Kluwer Academic Publishers: 117-141. Chapter 7. 

James, R.I,.; Dumoese, R.K.; Wenny, D.L. 1995. Borrytis cinerc.a carried by adult fungus 

gnats (Diptera: Sciardae) in container- nurseries. Tree Planters' Notes. 46(2): 48-53. 

Landis, R.D.; Tinus, R.W.; McDonald, S.E.; Barnett, J.P. 1989. Seedling nutrition and 

irrigation. In: The container tree nursery manual. Agric. Handb. 674. Washington, DC: 

U.S. Department of Agriculture. 1 19 p. Vol. 4. 

Landis, R.D.; Tinus, R.W.; McDonald, S.E.; Barnett, J.P. 1990a. The biological 

component: nursery pests and rnycorrhizae. In: The container tree nursery manual. Agric. 

Handb. 674. Washington, DC: U.S. Department of Agriculture. 171 p. Vol. 5. 

Landis, R.D.; Tinus, R.W.; McDonald, S.E.; Barnett, J.P. 1990b. Containers and growing 

media. In: The container tree nursery manual. Agric. Handb. 674. Washington, DC: U.S. 

Department of Agriculture, Forest Service. 88 p. Vol. 2. 

Landis, R.D.; l'inus, R.W.; McDonald, S.E.; Barnett, J.P. 1994. Nursery planning, 

development, and management. In: The container tree nursery manual. Agric. Handh. 674. 

Washington, DC': U.S. Department of Agriculture. 188 p. Vol. I. 

Pawuk, W.H. 1982. Transplanting germinated seeds into containers may retard growth. Tree 

Planters' Notes. 33(2): 22-23. 

Pawuk, W.H.; Barnett, J.P. 1981. Benomyl stimulates ecto~nycorrhizal development by 

Pi.so1ithlt.s tinc.toritts on sholtleaf pine grown in containers. Kes. Note SO-267. New Orleans, 

LA: U.S. Dcpattment of Agriculture, Forest Service, Southern Forest Experiment Station. 3 p. 

Wahlenberg, W.G. 1940. Longleaf pine: its use, ecology, ~.egeneration, protection, growth, 

ant1 management. Washington, DC: Charles Lathrop Pack Forestry Foundation. 429 p. 
Isarnett, James I?; Mc<;ilvray, .John M. 1997. Practical guidelines for 

producing longleaf pine seedlings in containers. Gen. Tech. Rep. SRS- 13. 

Asheville, NC: U.S. Department of Agriculture, Forest Service. Southern 

Research Station. 28 p. 

1,ongleaf pine, although widely distributed in the presettlement forest\ of the 

southern Coastal Plain, now occupies less than 10 percent of its original range. 

It is a highly desirable species because it resists tire, insects, and disease and 

produces excellent quality solid-wood products. Regeneration of the species 

either by natural methods or by planting of bare-root nur5ery stock has been 

difficult, and renewed interest in it has resulted it1 evalun~ion of new approaches 

to seedling establishment. Using container stock has greatly itnprovcd the 

success of' lonpleaf pine establishment. Practical guidelines arc presented that 

will help nursery personnel consistently produce good container stock that will 

survive well and initiate early height growth. 

Keywords: Nursery practices, Pirlrr,~ ptr1rr.srri.s Mill.. planting techniques, seed 

germination.