United States

Department of

Agriculture

Forest 

Service

Pacific Northwest

Research Station

Resource Bulletin

PNW-RB-262

October 2011

Federated States of Micronesia’s 

Forest Resources, 2006

Joseph A. Donnegan, Sarah L. Butler, Olaf Kuegler, and Bruce A. Hiserote

Yap Chuuk

Pohnpei

Kosrae

Kosrae

Yap

Chuuk

Pohnpei
Authors

Joseph A. Donnegan is an ecologist, Sarah L. Butler is an ecologist, Olaf 

Kuegler is a statistician, and Bruce A. Hiserote is an information management 

specialist, Forestry Sciences Laboratory, 620 SW Main Street, Suite 400, Portland, 

OR 97205-3028.

The Forest Service of the U.S. Department of Agriculture is dedicated to the principle of 

multiple use management of the Nation’s forest resources for sustained yields of wood, 

water, forage, wildlife, and recreation. Through forestry research, cooperation with the 

States and private forest owners, and management of the National Forests and National 

Grasslands, it strives—as directed by Congress—to provide increasingly greater service 

to a growing Nation.

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opportunity provider and employer.
Abstract

Donnegan, Joseph A.; Butler, Sarah L.; Kuegler, Olaf; Hiserote, Bruce A. 

2011. Federated States of Micronesia’s forest resources, 2006. Resour. Bull. 

PNW-RB-262. Portland, OR: U.S. Department of Agriculture, Forest Service, 

Pacific Northwest Research Station. 50 p.

The Forest Inventory and Analysis program collected, analyzed, and summarized 

field data on 73 forested field plots on the islands of Kosrae, Chuuk, Pohnpei, and 

Yap in the Federated States of Micronesia (FSM). Estimates of forest area, tree 

stem volume and biomass, the numbers of trees, tree damages, and the distribution of tree sizes were summarized for this statistical sample. Detailed tables and 

graphical highlights provide a summary of FSM’s forest resources and a comparison to prior vegetation mapping and inventory work.

Keywords: Federated States of Micronesia, Kosrae, Chuuk, Pohnpei, Yap, 

biomass, damage, Forest Inventory and Analysis, forest inventory, volume, 

land cover.
Summary 

The Forest Inventory and Analysis (FIA) program conducted a systematic inventory 

of the forests of Kosrae, Chuuk, Pohnpei, and Yap in the Federated States of Micronesia (FSM) in 2005 and 2006 to estimate forest area, tree stem volume, biomass, 

carbon storage, tree damages, and the composition and percentage cover of understory vegetation species. Seventy-three permanent field plots were installed in a 

variety of forest types. By using recently acquired high-resolution satellite imagery, 

land cover was mapped into five broad classes: forest, nonforest vegetation, urban, 

barren, and inland water. Soil survey information was used to help refine the 

classification of forests. Our estimates for this inventory are derived from a sample 

based on 161,917 acres on the four main islands in the FSM. Forest covers about 89 

percent of the FSM. About 3 percent of the landscape was classified as urban land. 

We estimated gross tree stem volume to be about 609 million cubic feet for all size 

classes including seedlings and saplings. Aboveground dry biomass for tree stems 

5 inches and greater was estimated to be about 9.2 million tons. Approximately 11 

percent of the trees sampled in the inventory had some form of damage. Damage by 

other vegetation was the most prevalent damage agent, followed by human disturbance. The most frequently identified damage types were lost apical dominance, 

vines in the crown, and conks. The FSM’s forests are characterized by a wide range 

of tree diameters with relatively high species diversity compared to other Pacific 

Islands. In total, 96 tree species and 206 understory species were measured on the 

FIA plots. The average number of tree species per one-sixth-acre plot was seven. 

Federated States of Micronesia foresters and ecologists were especially helpful with 

species identification in the field, knowledge of the landscape, and assistance with 

private and communal land access.
1

Federated States of Micronesia’s Forest Resources, 2006

Introduction

This report on the forest resources of the four largest islands of the Federated 

States of Micronesia (FSM) (fig. 1) was based on a cooperative forest inventory 

conducted in 2005 and 2006 by the U.S. Department of Agriculture, Forest Service, 

Pacific Northwest Forest Inventory and Analysis (FIA) program1 and Pacific Island 

foresters. This work is an adaptation of the national FIA inventory system and was 

tailored to help answer local, national, and international questions about the status 

and trends in tropical forested ecosystems. Our partnership has concentrated on 

sharing technical forestry skills among cultures and agencies. The fieldwork for 

this inventory was conducted by a multinational crew including FSM foresters and 

mainland U.S. foresters and ecologists.

The FIA partnership yielded a systematic, sample-based field inventory for 

forested lands in the FSM in conjunction with support for updating prior vegetation mapping work (Falanruw et al. 1987a, 1987b; MacLean et al. 1986; Whitesell 

et al. 1986) that estimated land cover and forest-type area. We also update the 

resource inventory work of MacLean et al. (1988) and extend the sample to include 

additional lands, information on understory species composition, detailed tree size 

distribution, biomass, carbon mass, and damages for living and dead trees. The 

inventory was designed to provide resource managers with a broad overview of the 

current situation so they can better manage their forested and nonforested lands, 

and manage or mitigate any changes in the resource. The summarization of the field 

data is intended to help managers plan sustainable land use practices as well as plan 

sustainable supplies of wood, control invasive species and erosion, manage disturbances such as fire, and mitigate damages caused by humans and other animals.

Objectives

The objectives of this inventory are to:

• Estimate the current area of forest land by forest type group and stand 

size class.

• Estimate tree volume, biomass, and carbon storage by species and 

diameter class.

• Estimate the numbers of trees affected by damaging agents, such as 

insects and diseases, and estimate the numbers of dead trees.

• Share measurement and analysis techniques among groups involved 

in the inventory.

1 The Forest Inventory and Analysis program is now part of the Resource Monitoring and 

Assessment program of the Pacific Northwest Research Station.
2

RESOURCE BULLETIN PNW-RB-262

Methods

Site Description

The FSM is an independent nation located in the northwestern Pacific Ocean and 

comprises four primary states: Chuuk, Kosrae, Pohnpei, and Yap. Each state, except 

Kosrae, has numerous outer islands and atolls that are grouped within the Caroline 

Islands chain spanning an ocean distance of about 1,800 miles east to west. The 

land area of the FSM totals about 270 square miles. This forest inventory covers the 

four largest land masses of Chuuk, Kosrae, Pohnpei, and Yap, making up about 253 

square miles (94 percent) of the total land area. The FSM signed a compact of free 

association with the United States (signed into law in 1986) and regularly partners 

with U.S. federal agencies toward the goal of sustaining natural resources.

Figure 1—The Federated States of Micronesia, part of the Caroline Islands chain, spans an ocean distance of approximately 1,800 miles 

east to west in the northwestern Pacific Ocean. Land cover was mapped from 2005 to 2006 QuickBird satellite data. The Forest Inventory and Analysis program collected data on the four largest islands of Chuuk, Kosrae, Pohnpei, and Yap.

Australia

New

Zealand

Indonesia

Yap

Chuuk Pohnpei

Kosrae

Federated States

of Micronesia

Kosrae

Chuuk

Yap

EQUATOR

0 4 8 12 16 2 Miles

o

Key

Urban

Nonforest vegetation

Barren

Water

Forest

Pohnpei
3

Federated States of Micronesia’s Forest Resources, 2006

The states within the FSM are distinct in vegetation and culture owing to vast 

separation by ocean and a corresponding east-west climatic gradient. Although hot 

and humid across the gradient, trending from west to east (Yap, Chuuk, Pohnpei, to 

Kosrae) precipitation increases and becomes less seasonal (fig. 2). Temperatures in 

the western states of Yap and Chuuk show slight seasonal increases for April and 

May; however, mean monthly temperatures are fairly consistent across states, varying within a narrow range of about 2 °F (fig. 3) (Western Regional Climate Center 

2009). The western states of the FSM are adjacent to a typhoon belt and occasionally experience major typhoons. The typhoons are characterized by heavy rainfall, 

strong winds, and coastal surges that inundate low-lying areas. Recent coastal 

surges from high sea levels in Kosrae and other low-lying areas (winter 2007–2009) 

caused severe flooding and coastal erosion. Changes in sea level and the frequency 

of coastal surges has become an immediate concern for Pacific Island inhabitants.

25

20

15

10

5

0

Precipitation (inches)

Month

Jan.

Feb.

March

April

May

June

July

Aug.

Sept.

Oct.

Nov.

Dec.

Average rainfall

 Yap

 Chuuk

 Pohnpei

 Kosrae

Figure 2—Across the Caroline Islands chain, moving west to east (Yap, Chuuk, Pohnpei, to Kosrae), 

annual precipitation increases and tends to exhibit less month-to-month variability.
4

RESOURCE BULLETIN PNW-RB-262

Geologically, the states are distinct. Yap is unique in its gentle topography, geological complexity, and lack of significant limestone exposure. The majority of Yap 

is composed of volcanic and metamorphic rock with some coral-derived sands and 

clay mangrove soils along the coastal margins (Mueller-Dombois and Fosberg 1998, 

Nedachi et al. 2001). Upland soils are generally well-drained, schist-derived loam 

and clay (Smith 1983). Chuuk is a nearly circular arc of 19 volcanic islands termed 

an “almost-atoll,” surrounded by a barrier reef (Laird 1983b, Mueller-Dombois and 

Fosberg 1998). Inland, the topography is steep and rugged with lowland coastal 

margins of organic peat mangrove soils along with some areas of fine sand. Upland 

soils are generally well drained with very deep stony silty clay loams (Laird 1983b). 

Pohnpei is a circular, high volcanic island with steep mountains, rolling hills, and 

extensive mangrove areas along its margins (fig. 4). Soils in the uplands are welldrained, stony clay loams, whereas those in the lowland mangroves are organic 

clays (Laird 1982). Kosrae is also a high volcanic island with steep topography 

and a band of relatively flat lowland coast of extensive mangroves (fig. 5). Upland 

soils are gravelly silty clay loams with thick silt loams occuring in mangrove areas 

(Laird 1983a).

Figure 3—Mean monthly temperatures across the Caroline Islands vary little seasonally (Western 

Regional Climate Center 2009).

79.0

79.5

80.0

80.5

81.0

81.5

82.0

82.5

83.0

Mean temperature (°F)

Month

Jan.

Feb.

March

April

May

June

July

Aug.

Sept.

Oct.

Nov.

Dec.

Yap

Chuuk

Pohnpei

Kosrae
5

Federated States of Micronesia’s Forest Resources, 2006

Figure 4—Pohnpei is a high volcanic island with varied topography supporting upland forests at higher elevations and mangrove species 

at the seaward margins.

Figure 5—Forest Inventory and Analysis field crews commute to work through Kosrae 

mangrove forests.

Joseph Donnegan

Falaniko Mika
6

RESOURCE BULLETIN PNW-RB-262

Vegetation Types

The native lowland vegetation has been heavily modified over thousands of years of 

human activity. Tree gardening and agroforestry has been practiced for millenia by 

using unique systems of guided vegetation succession and spatial rotation (Raynor 

and Fownes 1991), resulting in remnant agroforestry species occurring throughout 

the extensive, formerly settled landscape. Throughout the Pacific Islands, plants 

used for medicine and food are found in now-remote areas, likely owing to those 

areas formerly supporting more dense human populations. Most of these agroforest 

species are found on gently sloping or flat lands. A recent and more alarming trend 

is to cultivate species of commercial value on steeper slopes at higher elevation 

(e.g., kava), where forests are more intact and soils are much more likely to erode.

The vegetation types described below use the mapping work of Liu and 

Fischer (2007) as the basis for classification with the species composition derived 

by overlaying the 2005–2006 forest inventory plot data onto the mapped types. In 

our current classification systems, we avoid the terms “primary” and “secondary” 

forest; these terms suggest a dichotomy between disturbed and undisturbed forest, 

when in reality, these forests have been disturbed by humans multiple times over 

several thousand years. Additionally, the history of land use is uncertain, as is the 

time required to recover from secondary back to an undocumented primary forest.

Upland forest—

At higher elevations, especially on Pohnpei and Kosrae, dense native rain forest 

remains. Yap and Chuuk upland forest exists as patchy native remnants (MuellerDombois and Fosberg 1998). Listed in descending abundance (as is the case 

for all forest types in this section) the following species were found on forest 

inventory plots within the areas mapped as upland forest: Eugenia stelechantha,

Hibiscus tiliaceus, Spathodea campanulata, Cananga odorata, Pandanus cominsii,

Commersonia bartramia, Cyathea spp., Exorrhiza ponapensis, Musa spp., Aglaia 

ponapensis, Campnosperma brevipetiolata, Horsfieldia nunu, Adenanthera 

pavonina, Macaranga carolinensis, Myristica insularis, Elaeocarpus carolinensis,

Parinari laurina, Cyathea ponapeana, Ficus tinctoria, Pterocarpus indicus,

Barringtonia racemosa, Dendrocnide harveyi, Ficus prolixa, Glochidion spp.,

Syzygium carolinense, Antidesma kusaiense, Ficus spp., Elaeocarpus kusanoi,

Claoxylon carolinianum, Premna spp., Premna obtusifolia, Neubergia celebica,

Pandanus tectorius, Semecarpus venenosus, Barringtonia asiatica, Pangium edule,

Mangifera indica, Artocarpus altilis, Timonius spp., Antidesma spp., Ponapea 

hosinoi, Garcinia rumiyo, Psychotria spp., Pandanus spp., Diospyros ferrea,
7

Federated States of Micronesia’s Forest Resources, 2006

Morinda spp., Rhus taitensis, Cocos nucifera, Cycas spp., Trichospermum ikutai,

Araucaria spp., Fagraea berteriana, Ptychococcus ledermanninus, Calophyllum 

inophyllum, Aidia cochinchinensis, Cinnamomum spp., Pittosporum spp., Inocarpus 

fagifer, Cerbera manghas, Pandanus dubius, Cinnamomum carolinense, Cynometra 

ramiflora, Eugenia spp., Palaquium karrak, Ponapea ledermanniana, and 

Macaranga spp.

Palm forest—

Dominant species found on FIA plots that were mapped as palm forest include 

Exorrhiza ponapensis, Aglaia ponapensis, Cyathea spp., Eugenia spp., Pandanus 

cominsii, Sterculia palauensis, Syzygium carolinense, Campnosperma brevipetiolata,

Myristica insularis, Aidia cochinchinensis, Cananga odorata, Cinnamomum 

carolinense, Garcinia ponapensis, and Timonius spp.

Disturbed forest—

This forest type has been heavily disturbed recently and contains a mixture of native 

and nonnative species representing forests recovering from disturbance, native 

forests invaded by nonnatives, and forests that are establishing in disturbed areas 

from a mix of seed sources. Tree species include Hibiscus tiliaceus, Horsfieldia 

nunu, Elaeocarpus carolinensis, Adenanthera pavonina, Morinda citrifolia, and 

Neubergia celebica.

Mangrove forest—

Mangroves occur around the coasts of most islands in the FSM. They help to buffer 

storms, preserve the coastline, and offer wood and food resources. Dominant species 

found within this type are Bruguiera gymnorrhiza, Scyphiphora hydrophyllacea,

Xylocarpus granatum, Rhizophora mucronata, R. apiculata, Sonneratia alba, R. 

stylosa, Lumnitzera littorea, Hibiscus tiliaceus, Pandanus tectorius, Rhizophora spp.,

Morinda citrifolia, Thespesia populnea, and Calophyllum inophyllum.

Agroforest—

Agroforest in the tropical Pacific is characterized by an abundance of fruit and nut 

trees interspersed with other canopy species. Agroforest tends to occur within and 

near settlements. Some of the most common species found in this forest type include 

Hibiscus tiliaceus, Musa spp., Cananga odorata, Artocarpus altilis, Macaranga 

carolinensis, Glochidion spp., Areca catechu, Barringtonia racemosa, Cocos 

nucifera, Rhus taitensis, Pandanus spp., Mangifera indica, Premna obtusifolia,

Horsfieldia nunu, Swietenia mahogoni, Bruguiera gymnorrhiza, Averrhoa bilimbi,

Morinda citrifolia, Aidia cochinchinensis, Inocarpus fagifer, Heterospathe elata,
8

RESOURCE BULLETIN PNW-RB-262

Heritiera littoralis, Rhizophora apiculata, Pandanus tectorius, Ficus prolixa,

Pterocarpus indicus, Sonneratia alba, Citrus reticulata, Toona ciliata, Calophyllum 

inophyllum, Exorrhiza ponapensis, Adenanthera pavonina, Cyathea spp., Commersonia bartramia, Pittosporum spp., Swietenia macrophylla, Allophylus timorensis,

Eugenia spp., Ficus spp., Musa nana, Swietenia spp., and Carica papaya.

Inventory Methods

The FSM inventory was based on the FIA inventory design that was implemented 

across the mainland United States beginning in 2000. We adapted the national 

design to include additional branching and rooting forms, additional tree crown measurements, and special-interest species ranging from invasive plants to pathogens 

to culturally or economically important species of various life forms. Additionally, 

we used topography to define site productivity or drought resilience (for perhumid 

climates). In the mainland FIA program, plots are spaced within forest land on a 

3.3-mile grid. With the assistance of the government of the FSM, plots were spaced 

across all vegetation types at about 1.9-mile intervals, yielding a triple intensification 

of the mainland inventory plot grid.

The FIA plot cluster is composed of four 24-foot-radius subplots (fig. 6). Three 

of those subplots are equally spaced, as if on spokes of a wheel, around the central 

subplot. The distance from the middle of the central subplot to the middle of each 

subplot on the three spokes is 120 feet.

A variety of information was collected at the plot, subplot, and tree level (USDA 

FS 2005). Differences in forest-type conditions are also mapped. For example, roads 

that intersect subplots are mapped, as are clear boundaries in forest tree size classes. 

The primary variables collected include plot location, slope, aspect, elevation, subplot slope position and shape, tree species, diameters, heights, damages, branching 

and rooting forms, decay, epiphytic loadings, crown characteristics, tree locations, 

and regeneration information. The fieldwork for this inventory was performed in 

February 2005 and January to April 2006.

Analysis Methods

The FIA estimates that are derived for forest land are based on a system that uses 

aerial photography or satellite imagery to define different types of land (strata) 

across the landscape. The simplest stratification is separating land into forest and 

nonforest strata. However, stratifications can be assisted or refined by using ancillary 

data such as topography, soil information, life zone or climatically based information, and prior inventories of vegetation groups. Because boundaries and research 

questions often change through time, FIA generally chooses to post-stratify the plot 

sample by using a consistent spatial distribution of plots across forested landscapes.
9

Federated States of Micronesia’s Forest Resources, 2006

Forest Inventory and Analysis 

Pacific Islands Plot Design 

N 

Overall plot footprint: ~1.5 acres

Distance between subplot centers: 120 feet

Distance from subplot center to microplot center: 12 feet

1 

2 

4 3 

Plot 

Subplot Microplot 

6.8-foot-radius microplot: 

 seedlings + saplings

Key 

24-foot-radius subplot: 

 all trees (>5 inches 

 diameter at breast height)

Figure 6—The plot design used for the continental U.S. Forest Inventory and Analysis program was adopted with slight simplification 

for the inventory in the Pacific Islands.

The FSM stratification for estimating numbers of trees, volume, biomass, 

and carbon was conducted via a classification of 2005–2006 QuickBird satellite 

data. The initial land-cover classification divided the landscape into forest, urban, 

nonforest vegetation, barren, and water land types. At least 10 percent tree cover 

was used as the basis for the forest-land classification, and includes both agroforests 

and mangrove forests. Nonforest vegetation includes other vegetation types with 

less than 10 percent tree cover. A geographic information system was used to 

sum acreage for each type. The acreage each field plot represents was derived by 
10

RESOURCE BULLETIN PNW-RB-262

dividing the total acreage of forest by the number of field plots. Adjustments were 

made for plots that could not be visited owing to hazardous conditions or denial 

of access. Average stand size (mean diameters of trees) was expanded from the 

plots to the landscape level by using the same expansion factors. Note that the 

FIA stratification area differs from that of the area mapped for detailed vegetation 

classification.

Wood volume was estimated for individual trees by approximating the centroid 

method (Wood et al. 1990, Yavuz 1999) using tree height and two stem diameter 

measurements. These measurements are expanded to tree-level volume estimates by 

using equations for sections of a cone. Both gross stem volume and net stem volume 

estimates were calculated. Net stem volume subtracts damage and rotten defects 

from gross stem volume. Biomass for individual tree stems was estimated by using 

the specific gravity for known species (13 out of 101 species in the FSM had known 

specific gravities). For species where specific gravity was not known, an average 

specific gravity of 0.5 grams per cubic centimeter was used. These estimates of 

aboveground tree biomass are derived from bole volume and include only biomass 

for the main stem, excluding branches, roots, and foliage.

Traditional site productivity estimates require forest stand age, derived from 

the annual rings of forest trees. Because tropical trees do not produce consistent 

annual rings, a modified topographic relative moisture index (TRMI) (Parker 

1982) was examined as a proxy for site productivity. The TRMI used a weighted, 

additive combination of slope steepness, slope shape, and slope position to assess 

the potential moisture retention in a forested stand. Remeasurement data from 

these plots at the next inventory cycle will provide a better estimate of productivity 

than TRMI. In very wet environments, TRMI may be best considered a droughtresilience proxy, predicting where soil and water accumulates, owing to topography, 

across a landscape. We also recognize moisture is not likely to be the only factor 

limiting tree growth and that a prolonged excess of moisture can be detrimental to 

the growth of many tree species. In highly porous limestone-derived soils and karst 

topography, drainage may occur very rapidly, making moisture channeling less 

important than substrate water retention.

Forest-type mapping was conducted independently by the Pacific Southwest 

Region’s Remote Sensing Lab (S&PF-RSL) with support from FIA. Land cover 

polygons were generated from QuickBird imagery and labeled with assistance 

from FSM foresters. The 2005–2006 QuickBird satellite imagery was used for 

the detailed mapping and served as the basis for land cover estimates.
11

Federated States of Micronesia’s Forest Resources, 2006

Reliability of FIA Data

The area of forested land cover types classified from the QuickBird satellite imagery was assumed to be accurate and used as the basis for the expansion of the numbers of trees, tree volume, and tree biomass from the plot to the forest-type scale. 

Possible sources of error not accounted for in our estimates include errors in the 

land cover map owing to incorrect interpretation of the image, errors from rounding 

when working with pixel-based imagery, and measurement errors on field plots. 

Standard errors for the expansion of our estimates from field plots to the forested 

landscape were calculated according to the proportion of area occupied by forest. 

Forest areas were treated as known rather than estimated, and variance was calculated by using methods in Cochran (1977). Using one standard error as our basis 

for evaluation gives a 68 percent chance that the true total gross tree stem volume 

for the FSM lies between 508.4 and 645.8 million cubic feet. There is a 68 percent 

chance that the true number of trees (>1 inch diameter) for the FSM lies within the 

range of 86,180,204 to 102,070,530. Readers are cautioned to examine the standard 

errors associated with species-level estimates for the number of individuals and 

volume by tree species in table 1.

Resource Highlights

Land Cover

The FSM is currently about 89 percent forested, which includes agroforest and 

plantation forest vegetation (fig. 7, table 2). About 3 percent of the landscape was 

classified as urban land including roads, and about 9 percent was classified as 

nonforest vegetation including savanna and agricultural lands. The area used for 

land cover estimates totaled 161,917 acres.

Prior vegetation surveys (Falanruw et al. 1987a, 1987b; MacLean et al. 1986; 

Whitesell et al. 1986) delineated vegetation types by using 1975 and 1976 aerial 

photography, and estimated forest cover to be 83 percent of total land, including 

agroforest and plantations (fig. 7, table 2). About 1 percent of the land area was 

classified as urban. Nonforest vegetation was estimated to be about 15 percent of 

the total land cover. Total acreage from the 1986–1987 maps was 147,248 acres, 

calculated from the original maps that FIA scanned and digitized with support from 

S&PF-RSL.

Note that the methodology and the area sampled for land cover estimates differ 

from those used for prior estimates. The 1986–1987 work defined forested lands on 

the basis of a canopy cover of approximately ≥ 30 percent. The recent effort used a 

forest-land canopy threshold of ≥ 10 percent to remain consistent with recent FIA 
12

Table 1—Scientific names, common names, estimated number and gross volume, and standard errors for estimated totals measured as trees in the Federated States of Micronesia Estimated Standard Gross 

number error for volume 

Number	 (≥ 1 inch estimated	 (≥ 5 inch

Scientific name	 Common names	 measured diameter)	 number (±)	 diamete

Adenanthera pavonina L. metkam 38 1,339,253 803,501 25,859,49

Aglaia ponapensis Kaneh. karasyu, marasau 30 2,427,270 705,723 4,116,02

Aidia cochinchinensis Lour. kahmant 5 203,862 168,963 362,42

Allophylus timorensis (DC.) Bl. kitak, nguh, lah, ngu, angel, ngo 1 11,365 13,226 499,00

Antidesma kusaiense Kanihira 4 479,342 438,769 132,13

Antidesma spp. L. 1 221,861 212,128 Araucaria spp. Juss. 3 35,959 39,330 234,00

Areca catechu L. pu, buu, pu 23 912,405 988,802 860,96

Artocarpus altilis (Park.) Fosb. mai, kuru, mos, sou, maouli, mai 60 2,354,974 878,232 20,225,03

Averrhoa bilimbi L. kumim 5 187,027 189,719 125,68

Barringtonia asiatica (L.) Kurz wi, kawausu, bus-bus, gul, kun 5 334,581 339,691 168,37

Barringtonia racemosa (L.) Spreng. wihnmoar, kange, kaengal, waathul, son 29 1,428,024 938,652 1,453,89

Bruguiera gymnorrhiza (L.) Lam. lom, tongo, alol, song, ong 56 2,181,056 995,557 17,129,76

Calophyllum inophyllum L. tetau, isho, voi, eet, eetuh, ragich, biyuch, 7 73,376 47,211 5,919,33

rekich

Campnosperma brevipetiolata Volk. thong, elak, ka, ramluw, 57 1,675,205 635,247 45,629,06

Cananga odorata (Lam.) Hook. f. & Thoms. pwurenwai, ilanlang, rekich 109 5,296,449 2,609,831 8,669,12

Carica papaya L. mohmiyap, es, bweibwai, kippwau 1 10,207 12,820 49,41

Cerbera manghas L. sos 1 17,810 17,029 82,34

Cinnamomum carolinense Koidz. mattieu, masro, 2 31,147 20,996 212,19Cinnamomum spp. Schaeff. 2 23,973 26,220 996,37Citrus reticulata Blanco musrisrik, goligao 5 51,036 64,099 202,04

Claoxylon carolinianum Pax & Hoffm. koee 4 459,919 489,578 27,83

Cocos nucifera L. niu, koanu, nu, lu 55 739,566 218,516 14,372,67

Commersonia bartramia (L.) Merr. acarido, kahil, gagu, wapof, oun, tupuchol 32 2,410,929 1,788,203 703,96

Cyathea ponapeana (Hosok.) Glassman kattar, po 32 795,537 510,393 1,789,39Cyathea spp. Sm. 98 2,804,841 831,970 4,366,25

Cycas spp. L. 3 53,431 51,088 172,06Cynometra ramiflora L. kameu 1 11,986 13,110 1,141,93

Dendrocnide harveyi (Seem.) Chew 5 701,203 670,443 123,33

Diospyros ferrea (Willd.) Bakh. aringal 1 115,917 153,932

Elaeocarpus carolinensis Koidz. syatak, nanek 31 883,929 363,601 13,110,42

Elaeocarpus kusanoi Kaneh. maratte, opop 5 471,906 502,683 96,08

Eugenia spp. L. 5 519,874 407,975 503,11Eugenia stelechantha (Diels) Kaneh. kirekinwel, kahkarak, fukunnes, attieu 35 6,395,722 2,207,462 1,909,36

Exorrhiza ponapensis (Becc.) Burret kotop 290 5,147,637 1,948,624 67,694,26

Fagraea berteriana (Gilg & Bened.) Fosb. sair, seir 3 35,959 39,330 140,94

Ficus prolixa Forst. f. aoa, konya, giliau, aow, au 27 668,597 421,068 41,649,42

Ficus spp. L. 6 484,337 460,650 205,22
13

Table 1—Scientific names, common names, estimated number and gross volume, and standard errors for estimated totals measured as trees in the Federated States of Micronesia (continued)

Estimated Standard Gross 

number error for volum

Number	 (≥ 1 inch estimated	 (≥ 5 inch

Scientific name	 Common names	 measured diameter)	 number (±)	 diameteFicus tinctoria Forst. f. ahwahn, neen, shara, guwan, wach’guy, auwon 14 754,712 391,199 2,140,13

Garcinia ponapensis Laut. konpuil 1 19,161 16,400 110,05Garcinia rumiyo Fosb. rumiyo 4 143,833 175,965 107,36

Glochidion spp. J.R. & G. Forst. 21 1,575,214 853,365 1,018,69Heritiera littoralis Dry. marapinset, lum, rung, zwobott 5 95,804 82,001 5,336,82

Heterospathe elata (Becc.) Becc. buag bbuag 11 125,012 145,484 412,69

Hibiscus tiliaceus L. hau, kalau, lo, hulifui, gaal, sinifo 263 14,039,298 4,215,739 16,173,21

Horsfieldia nunu Kanehira 77 1,698,764 496,994 27,800,08

Inocarpus fagifer (Park.) Fosb. marrup, clark, buoy, anilla, kurrak 9 144,941 102,316 11,059,26

Lumnitzera littorea (Jack) Voigt weingal, oi, wei, wei, achoro 10 484,723 418,671 251,34

Macaranga carolinensis Volk. apwid, lo-lep, bith, aput 36 2,966,667 1,282,088 979,94

Macaranga spp. 1 9,306 12,357 22,48Mangifera indica L. kangit, mango, manga, manko 27 700,408 355,544 10,961,41

Morinda citrifolia L. weipwul, nonu, hi, lel, mangalueg, nen, nopur 6 197,874 167,431 467,47

Morinda spp. L. 1 115,917 153,932Musa nana Lour. tama 1 11,365 13,226Musa spp. 186 5,042,577 1,956,899Myristica insularis Kaneh. karara 43 1,086,235 411,630 19,402,71Neubergia celebica (Koord.) Leenhouts toa 11 392,362 240,448 813,12

Palaquium karrak Kanehira 1 11,986 13,110 2,658,75

Pandanus cominsii Hemsl. matal 19 3,015,649 1,052,041

Pandanus dubius Spr. pakoa, kipar-n-ai, meu yok,poak 1 17,810 17,029 48,91

Pandanus spp. 18 687,860 447,576 718,38Pandanus tectorius Park. hara, fach, choi, 15 608,153 531,836 326,27

Pangium edule Reinw. ex Bl. durien, rowal, 8 329,103 253,349 549,84

Parinari laurina A. Gray ais, aset, adidi, gritin, ais 17 811,308 540,527 7,145,58

Pittosporum spp. 3 43,134 30,927 1,304,04Ponapea hosinoi Kaneh. kattai 7 221,229 241,969 353,59Ponapea ledermanniana (Becc.) Engl. kattai 1 11,986 13,110 225,86

Premna obtusifolia R. Br. sobuk, orr, varovaro, fienkek, yar, umukau, nior 15 726,977 320,508 652,35Premna spp. 3 447,933 359,280

Psychotria spp. 3 143,033 167,159 135,46

Pterocarpus indicus Willd. lach 19 785,158 749,182 4,672,78

Ptychococcus ledermanninus (Becc.) 2 35,621 21,985 101,34

Moore & Fosb.

Rhizophora apiculata Bl. aak, akapa, sakasrik 45 837,690 436,295 22,669,97

Rhizophora mucronata Lam. akelel, karak, chia, roway, chia 45 862,236 465,366 15,250,73

Rhizophora spp. 7 108,338 106,919 326,64

Rhizophora stylosa Griff. 28 536,502 459,208 2,817,20
14

Table 1—Scientific names, common names, estimated number and gross volume, and standard errors for estimated totals measured as trees in the Federated States of Micronesia (continued)

Estimated Standard Gross 

number error for volum

Number	 (≥ 1 inch estimated	 (≥ 5 inch

Scientific name	 Common names	 measured diameter)	 number (±)	 diamete

Rhus taitensis Guill. g’lad, garahde 6 693,553 460,097 37,77

Scyphiphora hydrophyllacea Gaertn. gause 13 1,449,774 1,687,179 93,58

Semecarpus venenosus Volk. changath changad 25 339,250 246,982 1,890,87Sonneratia alba J.E. Sm. kwat, kotoh, folofol, abruk, sales 33 798,105 370,042 79,820,77Spathodea campanulata Beauv. rarningobchey 64 2,964,321 3,080,768 5,488,52Sterculia palauensis Kaneh. 6 334,485 286,296 699,18

Swietenia macrophylla King 1 19,161 16,400 170,10Swietenia mahogoni (L.) Jacq. moakumi, mahogany 3 294,501 342,726 98,14

Swietenia spp. Jacq. 1 11,365 13,226 77,66

Syzygium carolinense (Koidz.) Hosokawa 9 746,546 350,374 826,58

Thespesia populnea (L.) Sol. ex Correa miro, pone, panu, bangbeng, pona, okuran, 1 15,477 15,274 35,66

likokon

Timonius spp. DC. 4 262,981 308,580 907,97

Toona ciliata Roem. 2 38,322 32,801 1,035,45

Trichospermum ikutai Kaneh. wapof 4 37,222 30,269 273,21

Unknown 36 2,918,095 1,389,279 11,523,24

Unknown 0 3 57,482 49,201 1,441,59Unknown 14 1 115,917 153,932Unknown 20 2 125,222 166,290 38,18Unknown 5 1 141,568 164,750Xylocarpus granatum Koen. brok, pwulok, ploek brok, tui, yamgur, 48 918,673 419,361 34,716,71

punopun

 Total 2,324 94,125,367 7,945,163 577,122,81
15

Federated States of Micronesia’s Forest Resources, 2006

work in American Samoa, Guam, Palau, and the Northern Mariana Islands. The 

current survey mapped roads as urban land. Although the differences in interpretation methods and canopy cover thresholds between 1986/1987 and 2006 must be 

considered, trends suggest some conversions to urban land.

Figure 7—Slight increases in urban lands are evident throughout the Federated States of Micronesia over the 30-year period between 

1976 and 2006. However, making direct comparisons among the area of forested and nonforested land between inventories is complicated because of slightly different forest land definitions that were based on different tree cover percentages at each point in time.

Chuuk

0

10,000

20,000

30,000

40,000

50,000

60,000

70,000

80,000

90,000

Forest land

Nonforest 

 vegetation

Urban

Water, 

barren, other

Total

Land cover

Forest land

Nonforest 

 vegetation

Urban

Water, 

barren, other

Total

Land cover

Acres

25,000

20,000

15,000

10,000

5,000

0

1976

2006

Kosrae

1976

2006

Acres

30,000

25,000

20,000

15,000

10,000

5,000

0

Pohnpei

Forest land

Nonforest 

 vegetation

Urban

Water, 

barren, other

Total

Land cover

Forest land

Nonforest 

 vegetation

Urban

Water, 

barren, other

Total

Land cover

Acres

25,000

20,000

15,000

10,000

5,000

0

1976

2006

Yap

1976

2006

Acres
16

Table 2—Estimated area by land cover by island in the Federated States of Micronesia, 1976a and 2006b 1976 2006 Chuuk	 Kosrae	 Pohnpei	 Yap	 Total	 Chuuk	 Kosrae	 Pohnpei	 Land cover:c Acres Land cover: c Acres

Upland forest 1,547 14,470 41,869 6,260 64,146 Upland forest 4,145 18,231 48,300 

Palm forest 5 4,261 4,266 Palm forest 195 4,526 

Swamp forest 1,282 1,040 384 2,706 Swamp forest 1,128 244 

Mangrove 730 3,608 13,668 2,810 20,816 Mangrove forest 3,180 3,452 13,982 

Agroforest 5,229 4,535 14,057 5,790 29,611 Agroforest 10,614 3,686 14,608 Dwarf forest 171 3 174Atoll forest 13 13Plantation forest 2 15 17Coconut plantation 307 390 697

 Forested subtotal 7,514 24,066 74,926 15,244 121,749 Forested subtotal 18,134 26,496 81,659 

Nonforest vegetation: Nonforest vegetation:

Grassland or savanna 400 41 3,590 4,980 9,011 Savanna or other shrub/grass 684 15 2,440 

Secondary vegetation 610 2,640 6,768 1,357 11,375 Disturbed vegetation 771 650 2,214 

Cropland 5 5 189 109 307 Cropland 147 4 29 

Urban land 316 291 591 754 1,952 Urban builtup 774 313 972 

Unclassified 12 10 930 17 969 Urban cultivated 527 438 440 

Strand 10 10

Barren 13 6 5 18 41 Barren 43 40 14 

Marsh 555 63 429 394 1,440 Water 140 56 80 

Water 8 244 55 86 393 Marsh 549 151 330 

 Nonforest subtotal 1,929 3,300 12,556 7,713 25,499 Nonforest subtotal 3,636 1,667 6,519 

Total 9,443 27,366 87,482 22,957 147,248 Total 21,770 28,163 88,179 

a Figures for maps derived from 1976 aerial photography differ slightly from those published by Falanruw et. al (1987a, 1987b), Whitesell et al. (1986), and MacLean et al. (1986). Figures here were derived by scanning the historical maps and aggregating area totals with a geographic information system.b Figures for 2006 were summarized from the work of Liu and Fischer (2006), aggregating area totals with a geographic information system.c Note that classification schemes differ slightly from the 1986/1987 to 2006 map summaries. Additionally, the area surveyed, the imagery, and the 

methodology differ such that detailed change detection is not possible across land cover maps. 
17

Federated States of Micronesia’s Forest Resources, 2006

Productivity and Drought Resilience

Site productivity estimates are difficult to obtain in tropical environments because 

of a lack of consistent annual tree rings. The standard premise for site productivity 

hinges on determining how height or diameter changes with respect to tree age 

under particular site conditions; depending on site quality, a given tree species is 

expected to grow to a certain diameter or height given a certain age. Remeasurement of individual trees at the next inventory cycle will provide better estimates 

of site productivity by using growth over the specific period. For the present work, 

we estimated productivity as an additive index based on a site’s potential moisture 

accumulation owing to local topography (TRMI) (Parker 1982). The topographic 

relative moisture index may have utility in very wet environments as a predictor 

of resilience to occasional drought, because TRMI predicts moisture accumulation (and likely sediment/soil accumulation as well) based on topography. By 

using TRMI in this context, we classified about 46 percent of the forested lands in 

the FSM as highly drought resilient (fig. 8). Given the prevelance of steep slopes 

throughout Pohnpei, Chuuk, and especially Kosrae, water tends to run off and the 

potential for moisture accumulation lies in flat lands.

In a region of high precipitation, such as the FSM, the TRMI estimate of 

productivity may be less reliable than productivity estimates based on detailed soil 

sampling and mapping. For example, differences among coarse upland and clay 

lowland soils are dramatic with respect to soil organic matter and water holding 

capacity.

Figure 8—A topographic relative moisture index was used to predict drought resilience in the 

perhumid climate of the Federated States of Micronesia. Owing to the steep topography on Pohnpei, 

Kosrae, and Chuuk, water runs off quickly.

 10%

14,622

 25%

38,508

Forest land potential 

drought resilience

(Percentage of total forest 

area and acreage)

Low

Medium low

Medium

Medium high

High

Highest

 22%

32,769

4%

6,866

3%

5,179

 36%

54,412
18

RESOURCE BULLETIN PNW-RB-262

Forest Structure

In the FSM, we estimated stand size class on forested field plots to capture the predominant diameter of live trees in forest stands. The dominant size class (64 percent 

of acreage) tends to be medium sized, in the 5- to 10.9-inch diameter category (fig. 

9, table 3). About 31 percent of acreage is made up of stands in the 11- to 19.9-inch 

category, and only about 2 percent of acreage is dominated by very large trees 

in the 20- to 39.9-inch category. The smallest diameter class (less than 5 inches) 

represented about 3 percent of the forested acreage.

<5

5–10.9

11–19.9

20–39.9

3%

5,062

64%

97,900

31%

46,754

2%

2,640

Acres by stand size class (inches)

Figure 9—The stands that characterize the Federated States of Micronesia’s forests tend to be 

composed of larger diameter trees in the 5- to 10.9- and 11- to 19.9-inch categories.

The diameter distribution for trees in the FSM shows a “reverse-J” distribution 

for tree diameters, demonstrating that regeneration is abundant (fig. 10). Larger 

diameter classes are also well represented in these forests. Gap-phase replacement 

is typical for these forests, where one large tree dies, falls, and creates a gap that 

is quickly filled with new seedlings. As expected for most forests throughout 

succession, many small trees die before they grow into the larger diameter classes. 

For trees at least 5 inches in diameter, tree heights are predominantly in the 20- 

to 39-foot height classes (fig. 11). The tallest tree on an FIA plot was found on 

Pohnpei, a Xylocarpus granatum that measured 29.8 inches in diameter and about 

155 feet tall. The largest diameter tree also was found on Pohnpei, a Sonneratia 

alba measuring 79.3 inches in diameter and 141 feet tall.

Wood volume (fig. 12, tables 1, 4, and 5), biomass (fig. 13, table 6), and carbon 

storage (table 7) tend to be concentrated in the larger diameter classes in the FSM. 

This pattern is typical where there exists a wide variety of tree size classes, especially larger ones.
19

Table 3—Estimated number of live trees on forest land by species and diameter class

Diameter class (inches)

	 5.0–	 7.0–	 9.0–	 11.0–	 13.0–	 15.0–	 17.0–	 19.0–	 21.0–	 23.0–	 

Species	 < 5.0	 6.9	 8.9	 10.9	 12.9	 14.9	 16.9	 18.9	 20.9	 22.9	 24.9	 

Number of trees

Adenanthera pavonina 800,232 155,627 85,832 35,621 17,810 77,404 41,783 35,621 28,018 

Aglaia ponapensis 2,209,153 71,918 74,281 11,986 35,959 11,986 

Aidia cochinchinensis 141,568 31,147 19,161 11,986 Allophylus timorensis 11,365 

Antidesma kusaiense 443,721 35,621 

Antidesma spp. 221,861 Araucaria spp. 35,959 

Areca catechu 707,840 204,566 

Artocarpus altilis 1,679,535 111,136 94,309 133,594 66,417 30,954 53,147 42,318 20,414 61,575 30,954 Averrhoa bilimbi 141,568 34,094 11,365 Barringtonia asiatica 298,622 23,973 11,986 Barringtonia racemosa 1,199,593 168,499 23,973 23,973 11,986 

Bruguiera gymnorrhiza 1,282,315 191,608 136,537 107,169 214,337 76,643 95,804 38,322 38,322 Calophyllum inophyllum 9,306 20,670 11,365 

Campnosperma brevipetiolata 1,011,783 96,353 35,959 92,091 17,810 23,973 96,903 41,783 59,594 35,959 11,986 

Cananga odorata 4,211,048 560,522 340,746 113,537 23,973 15,477 19,161 11,986 Carica papaya 10,207 

Cerbera manghas 17,810 Cinnamomum carolinense 31,147 

Cinnamomum spp. 11,986 11,986 Citrus reticulata 20,414 30,622 

Claoxylon carolinianum 447,933 11,986 Cocos nucifera 26,842 339,544 305,511 67,670 Commersonia bartramia 2,237,738 142,593 21,292 9,306 

Cyathea ponapeana 447,933 131,850 131,850 71,918 11,986 Cyathea spp. 1,595,089 829,320 303,028 59,594 17,810 

Cycas spp. 17,810 35,621 

Cynometra ramiflora 11,986 Dendrocnide harveyi 665,582 35,621 Diospyros ferrea 115,917 

Elaeocarpus carolinensis 520,483 171,178 35,959 34,180 28,018 11,986 10,207 23,973 11,986 

Elaeocarpus kusanoi 447,933 23,973 Eugenia spp. 477,362 11,365 31,147 Eugenia stelechantha 6,288,859 53,431 17,810 17,810 17,810 

Exorrhiza ponapensis 686,614 637,379 1,033,622 1,931,210 749,894 74,281 34,638 

Fagraea berteriana 11,986 23,973 

Ficus prolixa 221,861 86,719 51,098 48,764 51,098 35,621 71,242 15,477 17,810 

Ficus spp. 463,667 11,365 9,306 
20Table 3—Estimated number of live trees on forest land by species and diameter class (continued)

Diameter class (inches)

	 5.0–	 7.0–	 9.0–	 11.0–	 13.0–	 15.0–	 17.0–	 19.0–	 21.0–	 23.0–	 

Species	 < 5.0	 6.9	 8.9	 10.9	 12.9	 14.9	 16.9	 18.9	 20.9	 22.9	 24.9	 

Number of trees

Ficus tinctoria 646,372 69,237 21,292 17,810 

Garcinia ponapensis 19,161 Garcinia rumiyo 115,917 27,917 Glochidion spp. 1,431,085 57,795 49,565 21,292 15,477 

Heritiera littoralis 38,322 19,161 Heterospathe elata 125,012 Hibiscus tiliaceus 11,477,399 1,369,868 695,444 341,424 77,849 53,341 23,973 

Horsfieldia nunu 570,870 178,313 267,366 109,467 246,951 81,449 127,277 35,621 17,810 35,621 

Inocarpus fagifer 30,526 9,306 9,306 19,161 19,161 19,161 

Lumnitzera littorea 385,581 87,777 11,365 Macaranga carolinensis 2,732,703 163,917 70,047 

Macaranga spp. 9,306 

Mangifera indica 342,101 73,272 65,133 41,161 30,954 15,477 27,463 30,954 11,986 30,954 15,477 

Morinda citrifolia 141,568 30,622 15,477 10,207 Morinda spp. 115,917 Musa nana 11,365 

Musa spp. 2,850,358 1,152,180 714,203 247,558 78,277 

Myristica insularis 597,244 67,106 115,052 43,134 71,918 35,959 11,986 11,986 47,945 35,959 23,973 

Neubergia celebica 221,861 81,449 53,431 17,810 17,810 

Palaquim karrak 

Pandanus cominsii 3,015,649 

Pandanus dubius 17,810 Pandanus spp. 527,149 130,736 29,976 

Pandanus tectorius 489,318 64,070 54,765 

Pangium edule 265,228 21,292 9,306 23,973 9,306 Parinari laurina 597,244 17,810 17,810 53,770 35,621 17,810 35,621 35,621 

Pittosporum spp. 11,986 19,161 11,986 

Ponapea hosinoi 149,311 59,932 11,986 Ponapea ledermanniana 11,986 

Premna obtusifolia 616,467 54,758 20,414 35,337 

Premna spp. 447,933 Psychotria spp. 115,917 17,810 9,306 

Pterocarpus indicus 597,244 23,973 11,986 31,147 21,292 68,919 9,306 21,292 

Ptychococcus ledermanninus 35,621 Rhizophora apiculata 156,855 134,126 86,850 229,930 134,126 76,643 19,161 

Rhizophora mucronata 191,608 191,608 229,930 114,965 134,126 Rhizophora spp. 108,338 Rhizophora stylosa 364,055 95,804 57,482 19,161 

Rhus taitensis 682,188 11,365 
21

Table 3—Estimated number of live trees on forest land by species and diameter class (continued)

Diameter class (inches)

	 5.0–	 7.0–	 9.0–	 11.0–	 13.0–	 15.0–	 17.0–	 19.0–	 21.0–	 23.0–	 

Species	 < 5.0	 6.9	 8.9	 10.9	 12.9	 14.9	 16.9	 18.9	 20.9	 22.9	 24.9	 

Number of trees

Scyphiphora hydrophyllacea 1,415,679 11,365 22,730 Semecarpus venenosus 115,917 55,833 120,972 37,222 9,306 

Sonneratia alba 238,681 19,161 38,322 29,368 19,161 95,804 19,161 106,011 38,322 

Spathodea campanulata 2,388,976 251,713 179,795 95,891 35,959 

Sterculia palauensis 238,681 57,482 19,161 19,161 Swietenia macrophylla 19,161 

Swietenia mahogoni 283,136 11,365 

Swietenia spp. 11,365 

Syzygium carolinense 686,614 11,986 11,986 23,973 11,986 

Thespesia populnea 15,477 

Timonius spp. 231,833 19,161 

Toona ciliata 19,161 19,161 

Trichospermum ikutai 9,306 9,306 9,306 9,306 

Unknown 2,677,156 58,514 15,477 15,477 27,463 30,954 15,477 15,477 19,161 11,986 

Unknown 0 19,161 19,161 19,161 

Unknown 14 115,917 

Unknown 20 115,917 9,306 

Unknown 5 141,568 Xylocarpus granatum 141,568 111,050 72,844 68,732 110,737 30,526 134,126 114,965 19,161 38,322  Total 66,890,074 9,309,950 5,803,396 4,757,044 2,814,143 1,146,061 837,507 680,344 286,971 408,377 317,892 2
22

RESOURCE BULLETIN PNW-RB-262

Figure 10—Small trees are abundant in the Federated States of Micronesia, indicating 

disturbance and regeneration also are abundant. There are many larger trees as well.

Figure 11—For trees greater than or equal to 5 inches in diameter, the most common heights 

attained range from 20 to 39 feet tall.

Number of trees by size class

Total trees in all classes: 94,125,367 

50

45

40

35

30

25

20

15

10

5

0

1.0–2.93.0–4.9

5.0–6.9

7.0–8.9

9.0–10.9

11.0–12.9

13.0–14.9

15.0–16.9

17.0–18.9

19.0–20.9

21.0–22.9

23.0–24.9

25.0–26.9

27.0+

Diameter (inches)

Trees (millions)

0

1

2

3

4

5

6

<10

10–19

20–29

30–39

40–4950–5960–6970–7980–89

90–99

100 +

Height (feet)

Number of trees (millions) 

Number of trees 

by height class

(≥5 inches diameter)
23

Federated States of Micronesia’s Forest Resources, 2006

Figure 12—The gross volume of wood is concentrated in the 10- to 14.9-inch diameter class.

5.0–9.9

10.0–14.9

15.0–19.9

20.0–24.9

25.0–29.9

Diameter (inches)

0

20

40

60

80

100

120

140

Gross volume (million cubic feet)

Volume by size class

Total volume in these size classes: 

577,122,816 cubic feet

Figure 13—Biomass is concentrated in the larger diameter size classes.

Biomass by size class

Total biomass in these size classes: 9,096,619 tons

3.0

2.5

2.0

1.5

1.0

0.5

0

Stem biomass (million tons) 

5.0–9.9

10.0–14.9

15.0–19.920.0–24.9

25.0+

Diameter (inches)

Table 4—Estimated volume of live trees on forest land by diameter class

Diameter class (inches)

< 5	 5–9.9	 10–14.9	 15–19.9	 ≥ 20 All sizes

Cubic feet

Gross volume 32,260,970 100,432,285 132,052,385 82,265,889 262,372,257 609,383,786

Net volume (≥ 5 in) 100,426,463 131,980,850 82,093,165 257,138,855 571,639,334
24

Species

Diameter class (inches)

5.0–6.9 7.0–8.9

9.0–

10.9

11.0–

12.9

13.0–

14.9

15.0–

16.9

17.0–

18.9

19.0–

20.9

21.0–

22.9

23.0–

24.9

25.0–

26.9

 Cubic feet

Adenanthera pavonina 790,088 723,575 453,178 387,196 2,244,925 1,756,090 3,082,844 2,239,815 2,013,04

Aglaia ponapensis 228,291 500,193 180,617 479,714 569,899 Aidia cochinchinensis 97,551 115,132 149,745 

Allophylus timorensis 499,009 

Antidesma kusaiense 132,130 

Araucaria spp. 234,005 

Areca catechu 860,963 

Artocarpus altilis 351,320 692,658 1,539,366 1,331,617 755,047 1,965,223 1,536,856 1,566,930 4,257,927 2,628,820 Averrhoa bilimbi 81,941 43,744 

Barringtonia asiatica 89,251 79,127 

Barringtonia racemosa 565,853 133,382 388,225 366,438 

Bruguiera gymnorrhiza 656,435 1,041,852 1,234,122 4,087,098 2,037,541 3,823,503 1,428,656 2,820,561 Calophyllum inophyllum 22,794 216,250 189,671 901,810 

Campnosperma brevipetiolata 425,879 275,074 1,562,787 299,552 761,776 4,713,459 2,117,733 3,549,930 3,510,941 1,793,098 9,691,386 Cananga odorata 2,611,914 2,506,452 1,202,161 345,652 543,819 920,705 538,426 

Carica papaya 49,418 

Cerbera manghas 82,349 

Cinnamomum carolinense 212,191 

Cinnamomum spp. 237,276 759,096 

Citrus reticulata 51,529 150,512 

Claoxylon carolinianum 27,830 

Cocos nucifera 242,480 5,110,511 6,982,698 2,036,988 

Commersonia bartramia 431,030 136,573 136,360 

Cyathea ponapeana 449,668 740,538 509,629 89,557 Cyathea spp. 2,409,614 1,384,397 413,236 159,004 

Cycas spp. 27,752 144,310 

Cynometra ramiflora 1,141,934 Dendrocnide harveyi 123,334 

Elaeocarpus carolinensis 737,769 332,388 401,405 1,409,660 598,859 416,146 2,284,462 1,392,541 1,536,173 

Elaeocarpus kusanoi 96,089 

Eugenia spp. 64,178 438,933 Eugenia stelechantha 219,022 131,510 423,761 1,135,076 

Exorrhiza ponapensis 2,119,988 9,192,001 32,580,935 19,169,244 2,699,948 1,932,152 

Fagraea berteriana 28,822 112,120 

Ficus prolixa 359,338 1,110,342 1,012,019 2,043,402 1,798,955 7,997,862 620,514 3,467,839 4,771,774 Ficus spp. 43,065 162,157 

Ficus tinctoria 269,710 106,340 1,764,089 

Garcinia ponapensis 110,053 

Garcinia rumiyo 107,363 

Glochidion spp. 212,681 359,030 202,774 244,205 Heritiera littoralis 528,104 978,781 3,829,937 Heterospathe elata 412,692 

Hibiscus tiliaceus 5,256,002 4,446,041 3,510,745 933,290 1,335,883 691,252 

Horsfieldia nunu 583,276 1,980,150 1,372,039 4,432,305 2,181,441 4,066,197 3,099,435 1,394,196 3,101,835 

Inocarpus fagifer 149,694 112,559 166,394 581,364 795,349 1,362,823 

Table 5—Estimated gross volume of live trees ≥5 inches diameter at breast height on forest land by species and diameter 
25

Species

Diameter class (inches)

5.0–6.9 7.0–8.9

9.0–

10.9

11.0–

12.9

13.0–

14.9

15.0–

16.9

17.0–

18.9

19.0–

20.9

21.0–

22.9

23.0–

24.9

25.0–

26.9

 Cubic feet

Lumnitzera littorea 190,583 60,761 

Macaranga carolinensis 528,290 451,652 Macaranga spp. 22,481 Mangifera indica 256,641 381,193 604,431 537,183 332,447 921,133 1,454,163 561,119 2,407,716 1,743,678 1,761,705 Morinda citrifolia 71,944 58,673 336,860 Myristica insularis 303,840 1,085,245 539,997 1,400,895 948,348 617,829 639,621 3,213,394 4,307,696 2,578,780 3,767,072 

Neubergia celebica 208,511 251,879 82,568 270,169 Palaquium karrak 

Pandanus dubius 48,912 Pandanus spp. 556,632 161,748 Pandanus tectorius 148,274 178,003 Pangium edule 65,416 62,105 300,445 121,874 Parinari laurina 102,827 116,846 777,791 745,328 674,747 2,050,507 2,677,534 

Pittosporum spp. 46,077 325,131 932,835 

Ponapea hosinoi 258,666 94,930 Ponapea ledermanniana 225,861 Premna obtusifolia 132,669 211,245 308,440 Psychotria spp. 69,209 66,257 Pterocarpus indicus 95,502 95,870 475,110 394,429 1,634,443 217,360 1,760,069 Ptychococcus ledermanninus 101,340 Rhizophora apiculata 795,752 1,448,387 1,804,800 7,246,822 5,798,818 4,375,628 1,199,763 Rhizophora mucronata 989,570 2,132,237 3,946,112 3,513,946 4,668,870 Rhizophora spp. 326,644 Rhizophora stylosa 1,192,604 544,585 705,546 374,470 Rhus taitensis 37,777 Scyphiphora hydrophyllacea 20,869 72,714 Semecarpus venenosus 186,905 939,635 551,407 212,931 Sonneratia alba 211,033 846,138 625,201 753,483 5,251,190 885,859 7,980,738 6,100,484 951,781 

Spathodea campanulata 954,101 1,390,610 1,079,957 619,166 1,444,688 

Sterculia palauensis 263,379 122,830 312,972 Swietenia macrophylla 170,104 Swietenia mahogoni 98,140 Swietenia spp. 77,665 Syzygium carolinense 29,257 85,432 321,407 390,491 Thespesia populnea 35,660 Timonius spp. 65,766 Toona ciliata 463,771 571,680 Trichospermum ikutai 28,010 38,339 95,065 111,797 

Unknown 213,046 125,767 134,333 361,218 1,186,474 1,055,855 790,758 2,593,415 1,276,253 1,948,780 Unknown 0 359,354 563,401 518,837 

Unknown 20 38,188 Xylocarpus granatum 380,634 354,801 746,614 2,732,423 680,045 4,995,571 5,768,626 2,161,994 2,864,206 

Total 29,796,297 38,070,754 66,293,998 62,387,756 35,935,865 33,623,526 40,654,019 18,380,187 35,181,336 33,205,687 32,618,154 

Table 5—Estimated gross volume of live trees ≥5 inches diameter at breast height on forest land by species and diameter 
26

Table 6—Estimated aboveground dry stem biomass of live trees ≥5 inches diameter at breast height on forest land by specdiameter class Diameter class (inches) 5.0–	 7.0–	 9.0–	 11.0–	 13.0–	 15.0–	 17.0–	 19.0–	 21.0–	 23.0–	 25.0–	 27.0–	 State Species 6.9	 8.9	 10.9	 12.9	 14.9	 16.9	 18.9	 20.9	 22.9	 24.9	 26.9	 28.9	 

Tons Chuuk Adenanthera pavonina 3,015 

Artocarpus altilis 2,750 3,080 11,595 4,868 11,784 19,720 18,356 35,842 41,029 

Cananga odorata 3,395 8,930 6,680 8,488 Cocos nucifera 2,003 53,607 56,402 9,816 Exorrhiza ponapensis 1,450 14,121 Ficus prolixa 1,004 1,047 4,779 5,899 9,685 

Glochidion spp. 2,908 3,746 3,811 Hibiscus tiliaceus 1,782 Lumnitzera littorea 1,120 

Macaranga carolinensis 4,322 1,098 

Mangifera indica 3,279 2,789 7,297 8,384 5,189 7,762 22,696 37,578 27,214 27,496 Morinda citrifolia 916 Premna obtusifolia 463 Rhizophora spp. 5,098 Thespesia populnea 557 Unknown 1,963 2,097 2,434 18,518 16,479 12,342 30,416 

Xylocarpus granatum 2,339 2,230 1,348 

Chuuk subtotal 30,251 31,033 87,402 81,799 45,307 50,091 57,531 22,026 73,420 68,244 57,911 

Kosrae Adenanthera pavonina 9,316 9,826 7,073 6,043 22,095 9,637 48,115 34,958 31,419 18,036 

Antidesma kusaiense 2,062 Artocarpus altilis 580 3,786 3,549 6,641 5,060 24,456 30,614 

Barringtonia racemosa 2,900 Bruguiera gymnorrhiza 693 Campnosperma brevipetiolata 773 4,643 4,675 9,042 12,252 25,214 Cananga odorata 3,541 Carica papaya 771 Cerbera manghas 1,285 Citrus reticulata 804 2,349 

Cocos nucifera 11,948 10,019 18,276 Cyathea spp. 12,138 6,528 4,064 2,482 

Cycas spp. 433 2,252 Dendrocnide harveyi 1,925 Elaeocarpus carolinensis 5,431 2,080 22,001 6,495 Eugenia stelechantha 3,418 2,053 6,614 17,716 

Ficus prolixa 4,605 16,283 11,016 25,993 28,077 124,827 54,124 74,475 82,293 

Ficus tinctoria 21,476 Hibiscus tiliaceus 15,806 13,082 1,431 2,840 

Horsfieldia nunu 9,103 30,905 21,414 69,177 34,047 63,463 48,374 21,760 48,412 18,905 

Mangifera indica 969 2,137 Morinda citrifolia 1,123 5,258 Neubergia celebica 3,254 3,931 1,289 4,217 Pandanus dubius 763 Pandanus spp. 4,554 Parinari laurina 2,183 2,480 4,118 15,820 14,322 43,524 56,834 Premna obtusifolia 3,297 Psychotria spp. 1,080 Ptychococcus ledermanninus 1,582 Rhizophora apiculata 2,607 Sonneratia alba 3,921 14,843 14,855 24,712 

 Kosrae subtotal 85,118 102,746 77,368 145,067 137,871 97,145 277,806 126,040 137,248 102,536 120,749 143,946 3
27

Table 6—Estimated aboveground dry stem biomass of live trees ≥5 inches diameter at breast height on forest land by specdiameter class (continued)

Diameter class (inches)

5.0–	 7.0–	 9.0–	 11.0–	 13.0–	 15.0–	 17.0–	 19.0–	 21.0–	 23.0–	 25.0–	 27.0–	 

State Species 6.9	 8.9	 10.9	 12.9	 14.9	 16.9	 18.9	 20.9	 22.9	 24.9	 26.9	 28.9	 

Tons

Pohnpei Adenanthera pavonina 1,468 12,943 17,771 

Aglaia ponapensis 3,563 7,807 2,819 7,487 8,895 

Aidia cochinchinensis 1,523 1,797 2,337 

Araucaria spp. 3,652 Artocarpus altilis 1,661 2,972 5,074 7,005 5,892 Barringtonia asiatica 1,393 1,235 

Barringtonia racemosa 5,579 2,082 6,059 5,719 

Bruguiera gymnorrhiza 10,245 14,255 18,137 60,324 31,801 59,675 22,298 44,022 

Campnosperma brevipetiolata 4,994 4,293 19,748 11,889 64,523 20,800 30,192 54,797 27,986 151,258 38,474 2Cananga odorata 37,370 26,648 12,083 5,395 14,370 8,403 

Cinnamomum carolinense 3,312 Cinnamomum spp. 3,185 10,189 Claoxylon carolinianum 434 Cocos nucifera 10,042 25,251 Commersonia bartramia 5,534 987 Cyathea ponapeana 7,018 11,558 7,954 1,398 Cyathea spp. 25,470 15,079 2,386 Cynometra ramiflora 17,823 Elaeocarpus carolinensis 6,084 5,188 4,185 9,347 35,655 21,734 23,976 62,446 

Elaeocarpus kusanoi 1,500 Eugenia spp. 8,906 Exorrhiza ponapensis 33,088 142,014 508,507 299,184 42,139 16,035 

Fagraea berteriana 450 1,750 Ficus tinctoria 2,981 520 Garcinia ponapensis 1,718 Glochidion spp. 1,300 Heritiera littoralis 8,242 15,276 59,776 Hibiscus tiliaceus 58,211 59,517 53,486 11,502 20,929 12,299 

Inocarpus fagifer 1,389 9,074 12,413 21,270 

Macaranga carolinensis 1,722 4,266 Mangifera indica 2,192 6,615 8,758 Myristica insularis 4,742 16,938 8,428 21,864 14,801 9,643 9,983 50,153 67,232 40,248 58,795 Palaquium karrak Pangium edule 678 4,689 Parinari laurina 12,391 Pittosporum spp. 719 5,074 14,559 

Ponapea hosinoi 4,037 1,482 

Ponapea ledermanniana 3,525 Premna obtusifolia 3,408 Pterocarpus indicus 1,550 1,556 7,712 4,288 19,412 19,579 Rhizophora apiculata 11,586 22,606 25,562 113,105 90,505 68,293 18,725 

Rhizophora mucronata 15,445 33,279 61,589 54,844 72,869 

Rhizophora stylosa 18,614 8,500 11,012 5,845 Sonneratia alba 3,294 13,206 5,836 11,760 81,958 13,826 109,717 95,213 8Spathodea campanulata 14,891 21,704 16,855 9,664 22,548 

Sterculia palauensis 4,111 1,917 4,885 Swietenia macrophylla 2,230 Syzygium carolinense 457 1,333 5,016 6,095 Timonius spp. 1,026 13,145 Toona ciliata 7,238 8,922 
28

Table 6—Estimated aboveground dry stem biomass of live trees ≥5 inches diameter at breast height on forest land by specdiameter class (continued) Diameter class (inches) 5.0–	 7.0–	 9.0–	 11.0–	 13.0–	 15.0–	 17.0–	 19.0–	 21.0–	 23.0–	 25.0–	 27.0–	 State Species 6.9	 8.9	 10.9	 12.9	 14.9	 16.9	 18.9	 20.9	 22.9	 24.9	 26.9	 28.9	 

Tons Unknown 674 3,203 40,477 19,919 

Unknown 0 5,609 8,793 8,098 

Xylocarpus granatum 1,267 1,572 6,568 36,332 7,892 77,968 90,034 33,743 44,703 40,836 

 Pohnpei subtotal 290,335 425,861 840,398 711,886 359,678 377,550 291,216 130,911 351,810 347,478 316,352 154,900 1,4

Yap Allophylus timorensis 7,788 

Areca catechu 13,437 Artocarpus altilis 493 973 3,808 2,269 5,631 

Averrhoa bilimbi 1,279 683 Barringtonia racemosa 353 

Bruguiera gymnorrhiza 1,314 1,125 3,465 

Calophyllum inophyllum 406 3,848 3,375 16,046 

Campnosperma brevipetiolata 879 Cocos nucifera 1,782 4,166 17,311 3,700 

Commersonia bartramia 1,194 1,144 2,128 Eugenia spp. 1,302 Ficus spp. 430 1,620 Ficus tinctoria 302 774 Garcinia rumiyo 2,514 Glochidion spp. 411 1,857 1,865 Heterospathe elata 6,441 Hibiscus tiliaceus 19,501 4,726 7,548 5,104 Inocarpus fagifer 947 1,757 2,597 

Lumnitzera littorea 1,855 948 

Macaranga carolinensis 2,201 1,685 Macaranga spp. 351 

Mangifera indica 726 Pandanus spp. 4,134 2,524 

Pandanus tectorius 2,314 2,778 Pangium edule 343 969 1,902 Premna obtusifolia 1,608 1,406 

Psychotria spp. 1,034 Pterocarpus indicus 2,115 7,118 3,528 8,990 

Rhizophora apiculata 833 Rhus taitensis 590 

Scyphiphora hydrophyllacea 326 1,135 Semecarpus venenosus 2,917 14,665 8,606 3,323 Swietenia mahogoni 1,869 Swietenia spp. 1,212 Trichospermum ikutai 437 598 1,484 1,745 

Unknown 2,652 Unknown 20 596 Xylocarpus granatum 2,334 1,736 3,737 6,314 2,722 

Yap subtotal 71,426 44,248 43,807 40,919 22,367 5,430 13,419 8,990 16,046 

 All FSM total 477,129 603,889 1,048,975 979,672 565,223 530,217 639,972 287,968 562,478 518,258 511,058 298,846 2,0

FSM = Federated States of Micronesia.
29

Table 7—Estimated carbon mass of live trees ≥5 inches diameter at breast height on forest land by species and diameter c

Diameter class (inches)

Species 5.0–6.9	 7.0–8.9	 9.0–10.9	 11.0–12.9	 13.0–14.9	 15.0–16.9	 17.0–18.9	 19.0–20.9	 21.0–22.9	 23.0–24.9	 25.0–26.

Tons

Adenanthera pavonina 6,166 5,647 3,536 3,022 17,519 13,704 24,058 17,479 15,709 Aglaia ponapensis 1,782 3,903 1,409 3,744 4,447 

Aidia cochinchinensis 761 898 1,169 

Allophylus timorensis 3,894 Antidesma kusaiense 1,031 

Araucaria spp. 1,826 

Areca catechu 6,719 Artocarpus altilis 2,742 5,405 12,013 10,392 5,892 15,336 11,993 12,228 33,228 20,515 

Averrhoa bilimbi 639 341 

Barringtonia asiatica 696 617 Barringtonia racemosa 4,416 1,041 3,030 2,860 Bruguiera gymnorrhiza 5,123 8,130 9,631 31,895 15,900 29,838 11,149 22,011 

Calophyllum inophyllum 203 1,924 1,687 8,023 Campnosperma brevipetiolata 3,323 2,147 12,196 2,338 5,945 36,783 16,526 27,703 27,399 13,993 75,629 

Cananga odorata 20,383 19,560 9,381 2,697 4,244 7,185 4,202 Carica papaya 386 Cerbera manghas 643 

Cinnamomum carolinense 1,656 

Cinnamomum spp. 1,592 5,094 Citrus reticulata 402 1,175 Claoxylon carolinianum 217 Cocos nucifera 1,892 39,881 54,491 15,896 

Commersonia bartramia 3,364 1,066 1,064 Cyathea ponapeana 3,509 5,779 3,977 699 Cyathea spp. 18,804 10,803 3,225 1,241 

Cycas spp. 217 1,126 

Cynometra ramiflora 8,911 

Dendrocnide harveyi 962 

Elaeocarpus carolinensis 5,757 2,594 3,132 11,001 4,673 3,248 17,827 10,867 11,988 

Elaeocarpus kusanoi 750 

Eugenia spp. 651 4,453 

Eugenia stelechantha 1,709 1,026 3,307 8,858 

Exorrhiza ponapensis 16,544 71,732 254,253 149,592 21,070 15,078 Fagraea berteriana 225 875 Ficus prolixa 2,804 8,665 7,898 15,946 14,039 62,413 4,842 27,062 37,238 Ficus spp. 215 810 Ficus tinctoria 1,642 647 10,738 

Garcinia ponapensis 859 Garcinia rumiyo 1,257 

Glochidion spp. 1,660 2,802 1,582 1,906 

Heritiera littoralis 4,121 7,638 29,888 Heterospathe elata 3,221 Hibiscus tiliaceus 46,759 39,553 31,233 8,303 11,884 6,150 Horsfieldia nunu 4,552 15,453 10,707 34,589 17,023 31,732 24,187 10,880 24,206 

Inocarpus fagifer 1,168 878 1,299 4,537 6,207 10,635 

Lumnitzera littorea 1,487 474 Macaranga carolinensis 4,123 3,525 
30Table 7—Estimated carbon mass of live trees ≥5 inches diameter at breast height on forest land by species and diameter c

Diameter class (inches)

Species 5.0–6.9	 7.0–8.9	 9.0–10.9	 11.0–12.9	 13.0–14.9	 15.0–16.9	 17.0–18.9	 19.0–20.9	 21.0–22.9	 23.0–24.9	 25.0–26.

Tons

Macaranga spp. 175 

Mangifera indica 2,003 2,975 4,717 4,192 2,594 7,188 11,348 4,379 18,789 13,607 13,748 

Morinda citrifolia 561 458 2,629 Myristica insularis 2,371 8,469 4,214 10,932 7,401 4,821 4,991 25,077 33,616 20,124 29,397 Neubergia celebica 1,627 1,966 644 2,108 Palaquium karrak 

Pandanus dubius 382 

Pandanus spp. 4,344 1,262 

Pandanus tectorius 1,157 1,389 Pangium edule 510 485 2,345 951 

Parinari laurina 1,091 1,240 8,255 7,910 7,161 21,762 28,417 

Pittosporum spp. 360 2,537 7,280 

Ponapea hosinoi 2,019 741 

Ponapea ledermanniana 1,763 Premna obtusifolia 1,035 1,649 2,407 

Psychotria spp. 540 517 Pterocarpus indicus 775 778 3,856 3,201 13,265 1,764 14,285 

Ptychococcus ledermanninus 791 

Rhizophora apiculata 6,210 11,303 14,084 56,552 45,253 34,146 9,363 

Rhizophora mucronata 7,722 16,639 30,794 27,422 36,435 Rhizophora spp. 2,549 

Rhizophora stylosa 9,307 4,250 5,506 2,922 

Rhus taitensis 295 Scyphiphora hydrophyllacea 163 567 Semecarpus venenosus 1,459 7,333 4,303 1,662 

Sonneratia alba 1,647 6,603 4,879 5,880 40,979 6,913 62,280 47,607 7,427 

Spathodea campanulata 7,446 10,852 8,428 4,832 11,274 Sterculia palauensis 2,055 959 2,442 

Swietenia macrophylla 1,115 Swietenia mahogoni 934 

Swietenia spp. 606 Syzygium carolinense 228 667 2,508 3,047 

Thespesia populnea 278 

Timonius spp. 513 

Toona ciliata 3,619 4,461 

Trichospermum ikutai 219 299 742 872 Unknown 1,663 981 1,048 2,819 9,259 8,240 6,171 20,238 9,960 15,208 

Unknown 0 2,804 4,397 4,049 Unknown 20 298 

Xylocarpus granatum 2,970 2,769 5,826 21,323 5,307 38,984 45,017 16,872 22,352 

 Total 238,565 301,945 524,488 489,836 282,611 265,108 319,986 143,984 281,239 259,129 255,529 
31

Federated States of Micronesia’s Forest Resources, 2006

Table 8—Average understory vegetation covera on Forest Inventory and Analysis field subplots 

by species 

Standard deviation

Number across subplots

Scientific name	 Cover	 of subplots	 where species was found

Percent

Abrus precatorius L. 80.0 1

Abutilon sp. P. Mill. 9.7 3 5.5

Acalypha lanceolata Willd. 8.7 15 8.1

Achyranthes bidentata Blume 45.0 2 49.5

Ageratum conyzoides L. 1.0 1

Allamanda cathartica L. 3.0 1

Allophylus timorensis (DC.) Blume 6.0 2 5.7

Alocasia macrorrhizos (L.) G. Don 5.8 4 2.5

Alpinia carolinensis Koidz. 3.0 1

Alpinia purpurata (Vieill.) K. Schum. 9.0 2 8.5

Ananas comosus (L.) Merr. 1.0 2 0.0

Angiopteris evecta (J.R. Forst.) Hoffman 9.4 14 6.8

Angiopteris sp. Hoffmann 9.0 1

Asplenium laserpitifolium Lamarck 4.9 7 3.6

Asplenium nidus L. 4.3 61 5.0

Asplenium pellucidum Lam. 1.5 2 0.7

Asplenium polyodon G. Forst. 2.0 2 1.4

Asplenium scolopendrium L. 4.0 2 0.0

Asplenium scolopendropsis F. Muell. 3.0 1

Asplenium sp. L. 5.5 24 4.3

Asplenium tenerum Forst. f. 3.0 1

Astronidium kusaianum Hosokowa 3.0 1

Astronidium ponapense (Kanehira) Markgraf 3.0 1

Bambusa sp. Schreb. 7.2 10 9.6

Bambusa vulgaris Schrad. ex J.C. Wendl. 28.8 4 34.7

Blechnum sp. Linnaeus 5.0 1

Blechnum orientale L. 1.0 2 0.0

Blechum pyramidatum (Lam.) Urb. 9.3 8 7.7

Bolbitis heteroclita (Presl) in C. Ch. 20.1 8 14.8

Bolbitis sp. Schott. 3.0 1

Number of Canopy and Understory Species

In addition to counting and measuring overstory trees, understory vegetation cover 

and layer heights were estimated for shrubs, forbs, vines, and grasses on FIA 

subplots where a species occupied at least 3 percent cover on that subplot (table 8). 

Tree seedlings that are less than or equal to 1 inch in diameter are also estimated 

as understory vegetation cover (table 9). Special interest species (e.g., rare, endangered, medicinal, or invasive) identified by island foresters were also noted when 

found. However, if a species covered less than 3 percent of a subplot and was not 

listed as special interest, it was not enumerated.

For the 2005–2006 inventory, 96 tree species and 206 understory species were 

measured on FIA plots. On a per-plot basis (approximately one-sixth acre), the 

mean number of tree species found was 7 (fig. 14).
32

RESOURCE BULLETIN PNW-RB-262

Table 8—Average understory vegetation covera on Forest Inventory and Analysis field subplots 

by species (continued)

Standard deviation

Number across subplots

Scientific name	 Cover	 of subplots	 where species was found

Percent

Bothriochloa bladhii (Retz.) S.T. Blake 35.0 1

Caesalpina bonduc (L.) Roxb. 2.7 3 1.5

Cassytha filiformis L. 33.0 5 25.6

Cayratia sp. Juss. 2.3 3 1.5

Cayratia trifolia (L.) Domin 3.0 1

Centotheca lappacea (L.) Desv. 6.1 8 7.8

Chromolaena odorata (L.) King & H.E. Robins. 11.5 24 18.3

Clerodendrum buchananii (Roxb.) Walp. 1.0 1

Clerodendrum inerme (L.) Gaertn. 5.0 1

Codiaeum sp. Juss. 1.0 1

Codiaeum variegatum (L.) A. Juss. 1.0 2 0.0

Colocasia esculenta (L.) Schott 12.3 7 21.3

Cordyline fruticosa (L.) A. Chev 1.7 10 0.8

Costus speciosus Smith 12.7 31 17.4

Crotalaria pallida Aiton 1.0 2 0.0

Curcuma australasica Hook. f. 5.0 2 2.8

Cyathula prostrata (L.) Blume 10.0 1

Cyperus sp. L. 2.5 12 2.9

Cyrtococcum accrescens (Trin.) Straph. 6.2 11 5.6

Cyrtosperma chamissonis (Schott) Merrill 3.7 6 2.7

Davallia pectinata J. Sm. 3.0 1

Davallia solida (Forster fil.) Swartz. Schrad 1.8 6 1.0

Davallia sp. Sm. 1.0 1

Decaspermum fruticosum J.R. Forst. 5.3 9 8.0

Dendrobium sp. Sw. 15.6 5 24.9

Derris elliptica (Wallich) Benth. 5.5 82 4.8

Derris trifoliata Lour. 6.4 37 8.0

Desmodium sp. Desv. 2.0 1

Desmodium triflorum (L.) DC. 6.5 2 2.1

Dieffenbachia seguine (Jacq.) Schott 10.0 1

Digitaria ciliaris (Retz.) Koel. 1.0 1

Dioscorea bulbifera L. 9.9 16 10.2

Dioscorea sp. L. 9.3 12 10.2

Diospyros sandwicensis (A. DC.) Fosberg 1.0 1

Diplazium sp. Sw. 8.0 5 5.2

Elatostema sp. J.R. & G. Forst 6.7 3 3.2

Elephantopus mollis Kunth 4.0 2 4.2

Eleusine indica (Linnaeus) Gaertn. 5.0 1

Eleutheranther ruderalis (Sw.) Schultz-Bip. 5.0 1

Embelia palauensis Mez 1.0 1

Entada phaseoloides (L.) Merr. 2.0 2 1.4

Eragrostis sp. von Wolf 40.0 1

Eurya japonica Thunb. 1.0 1

Eurya japonica var. nitida Thunb. (Korth.) Dyer 2.0 2 1.4

Fimbristylis dichotoma (L.) Vahl 1.0 1

Fimbristylis ferruginea (L.) Vahl 1.0 2 0.0

Fimbristylis globulosa (Retz.) Kunth 1.0 2 0.0

Flacourtia rukam Zoll. & Moritzi 5.0 1

Flagellaria indica Linnaeus 8.3 8 10.5
33

Federated States of Micronesia’s Forest Resources, 2006

Table 8—Average understory vegetation covera on Forest Inventory and Analysis field subplots 

by species (continued)

Standard deviation

Number across subplots

Scientific name	 Cover	 of subplots	 where species was found

Percent

Flagellaria sp. L. 6.3 20 5.4

Freycinetia ponapensis Martelli 6.1 44 4.0

Geophila repens (Linnaeus) I.M. Johnston 7.0 1

Gleichenia linearis (Luers.) Fosberg 35.8 8 27.2

Gynochthodes ovalifolia (Val.) Kaneh. 2.5 2 0.7

Haplopteris elongata (Sw.) E. H. Crane 1.0 1

Hedychium coronarium J. Koenig 3.0 1

Hedyotis cornifolia Kaneh. 35.0 1

Hedyotis sp. L. 1.7 3 1.2

Helicteres angustifolia L. 1.0 1

Hibiscus rosa-sinensis L. 1.7 3 0.6

Histiopteris incisa (Thunb.) J. Sm. 4.5 2 5.0

Hoya schneei Schltr. 6.3 24 6.2

Hoya sp. R. Br. 3.0 3 2.0

Hymenophyllum sp. Sm. 9.2 5 10.6

Hypolytrum nemorum sensu Parham, non Spreng. 6.1 12 8.9

Hypolytrum sp. Pers. 1.0 1

Hyptis capitata Jacq. 6.7 10 5.8

Ipomea sp. L. 10.8 5 16.8

Ipomoea littoralis Blume 4.3 3 1.5

Ischaemum polystachyum J. S. Presl. 46.0 7 35.7

Ischaemum sp. L. 10.4 12 12.7

Ixora casei Hance 6.0 19 5.0

Ixora trianthia Volkens 4.0 1

Lantana camara L. 3.0 1

Leea sambucina (L.) Willd. 6.3 7 4.7

Lindsaea decomposita Holttum, Fl. Malaya 3.0 1

Linsaea sp. Dry. ex Sm. 1.0 1

Ludwigia octovalis (Jacquin) Raven, Kew 3.0 1

Luffa cylindrica (Linnaeus) Roem. Syn. Pepon. 5.0 1

Lycopodiella cernua (L.) Pic. Serm. var. cernua 15.0 1

Lycopodiella cernua (L.) Pic. Serm. var. curvata 45.0 2 21.2

(Sw.) Kartesz & Gandhi

Lycopodium sp. L. 3.7 3 0.6

Lygodium scandens (L.) Sw. 3.0 1

Lygodium sp. Sw. 3.0 1

Macropiper puberlum Benth. 1.0 1

Maesa caroninensis Mez 2.7 3 1.5

Manihot esculenta Crantz 8.0 15 10.0

Mapania pandanophylla Aubl. 3.0 1

Melastoma malabathricum L. 5.1 12 6.2

Merremia peltata (L.) Merrill 18.9 79 22.3

Merremia sp. Dennst. ex Endl. 10.0 3 5.0

Microgramma lycopodioides (L.) Copeland 10.0 2 0.0

Microlepia speluncae (L.) T. Moore 6.5 2 5.0

Microsorum scolopendria (Burm. f.) 5.9 7 4.3

Microstegium glabratum (Brongn.) A. Camus 1.8 4 1.0

Mucuna platyphylla A. Gray 8.0 1
34

RESOURCE BULLETIN PNW-RB-262

Table 8—Average understory vegetation covera on Forest Inventory and Analysis field subplots 

by species (continued)

Standard deviation

Number across subplots

Scientific name	 Cover	 of subplots	 where species was found

Percent

Mussaenda frondosa L. 1.0 2 0.0

Myrtella bennigseniana (Volkens) Diels 20.0 1

Nepenthes mirabilis Druce 4.7 10 4.0

Nephrolepis acutifolia (Desv.) Christ 5.0 1

Nephrolepis biserrata (Sw.) Schott 35.0 2 28.3

Nephrolepis hirsutula (J.R. Forst.) K. Presl 18.3 3 11.6

Nephrolepis obliterata (R. Br.) J. Sm. 27.4 28 28.3

Nephrolepis saligna Carr. 9.1 22 9.1

Nephrolepis sp. Schott 9.7 29 11.1

Nothocnide repanda (Blume) Blume 4.3 4 4.0

Nypa fruticans Wurmb, Verh. Batav. Gen. 1.0 1

Oplismenus compositus (Linnaeus) Beauv. 3.0 1

Oplismenus hirtellus (L.) Beauv. var. setarius 16.5 4 16.7

(lam.) F.M. Bailey

Oplismenus sp. Beauv. 6.3 8 6.1

Pachygone ledermannii Deils 2.5 2 0.7

Paspalum conjugatum Berg. 5.9 7 5.7

Paspalum orbiculare L. 4.0 4 4.1

Passiflora foetida L. 3.0 1

Passiflora sp. L. 10.0 1

Pennisetum polystachyon (L.) J.A. Schultes 12.0 3 15.7

Pennisetum sp. L.C. Rich ex Pers. 8.0 1

Phragmites karka (Retz.) Trin. ex Steud. 5.0 1

Phymatosorus grossus (Langsd. & Fisch.) Brownlie 7.0 1

Piper betel L. 1.0 1

Piper methysticum G. Forst. 6.1 8 3.8

Piper ponapensis C. de Candolle 8.2 89 7.9

Piper sp. L. 19.1 7 27.9

Polygala paniculata L. 1.5 2 0.7

Polypodium cyathoides Sw. 2.0 1

Polypodium punctatum (Raddi) Hook. 3.0 1

Polypodium sp. L. 2.8 5 1.5

Polyscias grandifolia Volk. 4.3 4 3.8

Polyscias sp. J.R. Forst. & G. Forst. 1.0 1

Polyscias subcapitata Kanehira 5.5 8 4.4

Procris pedunculata (J.R. Forst.) Wedd. 4.7 26 2.9

Psychotria hombroniana (Baill.) Fosberg 3.0 3 2.0

Pteris plumula Desv auct. Non Retz. 3.8 6 1.3

Pteris spinescens C. Presl 5.0 6 2.8

Pteris tripartita Sw. 3.0 1

Puera sp. DC. 3.5 2 0.7

Pueraria phaseoloides (Roxb.) Benth 3.0 1

Rubus moluccanus L. 13.6 7 13.1
35

Federated States of Micronesia’s Forest Resources, 2006

Table 8—Average understory vegetation covera on Forest Inventory and Analysis field 

subplots by species (continued)

Standard deviation

Number across subplots

Scientific name	 Cover	 of subplots	 where species was found

Percent

Rumohra aristata (Forst.) Ching 3.0 1

Sacciolepis indica (L.) Chase 18.7 3 17.0

Salacia chinensis L. 10.3 3 12.7

Salacia naumanni Engl. 20.0 2 14.1

Scaevola sericea Vahl var. taccada (Gaertn.) 8.8 4 5.4

Thieret & B. Lipscomb

Schizaea dichotoma (L.) Sm. 1.5 2 0.7

Scirpodendron ghaeri Merrill 3.0 1

Scleria lithosperma L. (Sw.) 8.6 16 11.6

Scleria sp. Berg. 5.2 5 5.9

Selaginella sp. Beauv. 7.0 1

Sida sp. L. 1.0 2 0.0

Sphagneticola trilobata (L.) Pruski 4.0 2 1.4

Stachytarpheta jamaicensis (L.) Vahl 3.0 1

Syzgium stelechanthum (Diels) Glassman 5.0 1

Tabernaemontana sp. L. 4.0 1

Tacca leontopetaloides (L.) Kuntze 1.5 2 0.7

Tectaria grandifolia (Presl) Copel. 10.1 12 7.5

Tectaria sp. Cav. 7.3 17 11.2

Thelypteris heterocarpa (Blume) Morton 13.4 7 9.5

Thelypteris maemonensis (W.H. Wagner & 21.3 3 15.8

Grether) Stone

Thelypteris sp. Schmidel 12.3 40 12.9

Thelypteris truncata (Poir.) K. Iwats. 6.0 3 3.6

Trichomanes sp. L. 1.0 1

Triphasia trifolia (Burm. f.) P. Wilson 2.0 4 2.0

Unknown annual grass 1 1.0 1

Unknown fern 0 0.0 11 0.0

Unknown forb 0.0 60 0.0

Unknown grass 1 10.5 27 23.6

Unknown perennial grass 1 3.3 4 3.3

Unknown perennial grass 1a 1.0 2 0.0

Unknown perennial grass 2 2.0 1

Unknown perennial grass 2a 1.3 3 0.6

Unknown sedge 0.0 1

Unknown shrub 0.0 32 0.0

Unknown sp. 4.2 20 2.9

Unknown vine 5.0 1

Vigna marina (Burm.) Merrill 10.0 1

Wollastonia biflora (L.) DC. 4.7 3 1.5

a Percentage cover of “1” indicates cover less than or equal to 1 percent. Cover estimates are averaged among subplots 

where each species was found. In total, 252 subplots were surveyed for vegetation cover. The number of subplots where 

a species was found and the standard deviation for cover estimates provide an idea of spatial variability for each species 

across the island group. Understory vegetation includes the epiphytes and climbing vines.
36

RESOURCE BULLETIN PNW-RB-262

Table 9—Average understory tree covera on Forest Inventory and Analysis field 

subplots by species 

Standard deviation

Number across subplots

Scientific name	 Cover	 of subplots	 where species was found

Percent

Acacia spp. 2.0 1

Adenanthera pavonina 6.2 17 7.1

Aglaia ponapensis 9.3 74 10.0

Aidia cochinchinensis 6.7 11 9.8

Albizia lebbeck 2.0 1

Angiopteris evecta 2.5 2 0.7

Annona muricata 1.0 1

Antidesma kusaiense 3.5 6 0.8

Antidesma sphaerocarpum 1.5 2 0.7

Antidesma spp. 3.0 1

Areca catechu 3.4 5 1.5

Artocarpus altilis 1.4 12 0.7

Averrhoa bilimbi 1.0 1

Barringtonia racemosa 5.3 12 4.8

Bruguiera gymnorrhiza 1.8 21 1.3

Calophyllum inophyllum 4.7 3 4.7

Campnosperma brevipetiolata 2.1 10 1.4

Cananga odorata 1.9 10 0.7

Carica papaya 1.0 1

Cerbera manghas 1.0 1

Cinnamomum carolinense 2.0 1

Cinnamomum spp. 3.0 1

Claoxylon carolinianum 2.8 4 0.5

Cocos nucifera 2.5 37 2.0

Commersonia bartramia 5.4 5 2.3

Crateva religiosa 1.3 4 0.5

Cyathea ponapeana 4.7 13 3.1

Cyathea spp. 7.6 33 5.9

Cynometra ramiflora 4.0 1

Dendrocnide harveyi 3.0 2 2.8

Diospyros elliptica 4.0 2 1.4

Discocalyx ponapensis 2.5 2 0.7

Elaeocarpus carolinensis 2.4 5 1.5

Eucalyptus spp. 5.0 1

Eugenia stelechantha 4.4 35 3.0

Exorrhiza ponapensis 7.9 25 6.3

Ficus spp. 4.6 5 3.6

Ficus tinctoria 2.3 15 1.4

Ficus virens 3.0 1

Garcinia rumiyo 2.8 4 2.4

Garcinia spp. 3.0 1

Glochidion ramiflorum 3.5 8 2.8

Glochidion spp. 3.1 8 2.0

Heritiera littoralis 7.0 4 9.0

Heterospathe elata 42.5 2 10.6

Hibiscus tiliaceus 4.4 34 4.9

Horsfieldia nunu 2.7 19 1.7

Inocarpus fagifer 7.0 5 7.4

Leucaena leucocephala 6.0 1

Macaranga carolinensis 4.5 37 4.2
37

Federated States of Micronesia’s Forest Resources, 2006

Table 9—Average understory tree covera on Forest Inventory and Analysis field 

subplots by species (continued)

Standard deviation

Number across subplots

Scientific name	 Cover	 of subplots	 where species was found

Percent

Mangifera indica 2.8 12 1.9

Melochia aristata 1.0 2 0.0

Meryta senfftiana 1.0 1

Metroxylon amicarum 5.5 2 6.4

Morinda citrifolia 2.2 43 2.0

Morinda spp. 10.0 1

Musa spp. 3.5 24 2.7

Mussaenda frondosa 1.0 1

Myristica hypargyraea 1.0 2 0.0

Myristica insularis 5.5 15 4.7

Neubergia celebica 4.8 4 3.5

Pandanus cominsii 14.0 72 15.2

Pandanus dubius 4.0 1

Pandanus ponapensis 5.0 2 0.0

Pandanus spp. 11.7 24 13.8

Pandanus tectorius 4.7 12 4.2

Pangium edule 2.0 2 1.4

Parinari laurina 29.2 9 26.1

Pemphis acidula 1.0 1

Pipturus argenteus 6.5 2 4.9

Pisonia grandis 1.0 2 0.0

Ponapea hosinoi 7.5 2 6.4

Premna obtusifolia 3.0 13 3.0

Premna spp. 2.0 2 0.0

Psychotria spp. 3.6 7 1.7

Pterocarpus indicus 4.3 3 2.3

Rhizophora apiculata 2.1 13 1.7

Rhizophora mucronata 1.3 3 0.6

Rhizophora spp. 1.5 2 0.7

Rhizophora stylosa 4.0 2 2.8

Rhus taitensis 2.1 10 1.1

Scyphiphora hydrophyllacea 7.7 3 10.7

Semecarpus venenosus 2.9 9 2.1

Sonneratia alba 1.3 4 0.5

Spathodea campanulata 12.3 7 13.8

Swietenia macrophylla 7.0 2 4.2

Swietenia mahogoni 4.0 1

Syzygium carolinense 1.0 3 0.0

Syzygium samarangense 1.0 1

Terminalia catappa 1.0 1

Timonius spp. 2.8 4 1.7

Trichospermum ikutai 4.0 2 4.2

Unknown 0 1.0 1

Unknown 14 13.5 2 9.2

Unknown 3 5.0 1

Xylocarpus granatum 2.1 21 1.9

a Percentage cover of “1” indicates cover less than or equal to 1 percent. Cover estimates are averaged among 

subplots where each species was found. A total of 252 subplots were surveyed for vegetation cover. The number 

of subplots where a species was found and the standard deviation for cover estimates provide an idea of spatial 

variability for each species across the island group.
38

RESOURCE BULLETIN PNW-RB-262

Figure 14—For the 2005–2006 inventory, the average number of tree species found per 

one-sixth-acre plot was seven.

Tree Damage and Mortality

We estimated about 11 percent of the individual trees (≥ 5 inches diameter at breast 

height) in the FSM show some sign of damage (table 10). The most prevalent damage types are lost apical dominance (damage to the primary growing leader), vines 

in crowns, and conks (shelf fungus indicating rot) (fig. 15). Of the damaged trees, 

the prevalence of lost apical dominance was high (34 percent) often indicating damage to the central growing leader from insects, disease, or physical damage. Vines 

in the crowns were also common (27 percent of damages), although their effect on 

their supporting tree hosts was not quantified. Effects ranged from some additional 

weight to instances of strangulation or smothering. For the identifiable damaging 

agents, damage by other vegetation, damage from humans (silvicultural/cutting), 

and weather ranked as the most prevalent primary damage agents (fig. 16).

About 1.5 percent of the trees sampled during the inventory were dead. The 

most prevalent identifiable dead trees were Cyathea spp. (16.6 percent of total dead), 

Hibiscus tiliaceus (10 percent), and Cyathea ponapeana (8 percent) (fig. 17).

0

2

4

6

8

10

12

14

16

18

20

1–2 3–4 5–6 7–8 9–10 11–12 13–14 14–15

Number of plots

Number of tree species on Forest Inventory and Analysis plots
39

Federated States of Micronesia’s Forest Resources, 2006

Figure 15—Loss of apical dominance is very common in the Federated States of Micronesia. 

Damage from vines also was prevalent (recorded when the vines occupied 20 percent or more of 

the crown). Conks (fruiting shelf fungi indicating rot) were also common damages.

Figure 16—Disturbance from other vegetation and damage from humans were the most common 

identifiable damaging agents for trees.

33%

27%

16%

10%

5%

4%

3% 2%

Primary damage agent

Vegetation

Unknown

Silvicultural/cutting

Weather

Insect

Physical

Disease

Fire

34%

27%

14%

13%

4%

3%2% 3%

Type of tree damage

Loss of apical dominance

Vines in the crown

Conks

Open wounds

Broken or dead branches

Cracks and seams

Damaged buds/foliage

Other
40

RESOURCE BULLETIN PNW-RB-262

Figure 17—Dead trees were fairly abundant in the Federated States of Micronesia. Cyathea spp., 

Hibiscus tiliaceus, and Cyathea ponapeana were the most common dead trees of those species 

identified.

0

2

4

6

8

10

12

14

16

18

Dead trees (percent)

Species

Cyathea spp.

Campnosperma brevipetiolata

Hibiscus tiliaceus

Cyathea ponapeana

Musa spp.

Swietenia macrophylla

Cananga odorata

Rhizophora apiculata

Xylocarpus granatum

Adenanthera pavonina

Exorrhiza ponapensis

Myristica insularis

Semecarpus venenosus

Parinari laurina

Epiphytes

In the moist environment of the tropics, many plant species are found growing on 

longer lived trees. These epiphytes use the trees primarily for support, but they also 

use space, moisture, and nutrients that might otherwise be used by the tree. When 

the epiphytes accumulate over many years, their weight can be excessive, leading 

to the breakage of branches and occasionally snapping the stems of trees. In the 

FSM, we rated epiphytic loading on trees as a summation of loading on the bole, 

branches, and canopy. We estimate that about 55 percent of the trees (≥ 5 inches 

diameter at breast height) in the FSM had few to no epiphytes, and 45 percent of 

the trees had moderate to high amounts of epiphytes (table 11).
41

Table 10—Number of trees by primary damage type and species for all trees

No Broken	 Broken	 Broken	 	 Cracks/	 Damaged	 Loss of apical	 Open	 

Species	 damage	 bole	 or dead	 roots	 Conks	 seams	 foliage/shoots	 dominance	 wounds	 

Number of trees

Adenanthera pavonina 1,031,561 28,018 239,671 11,986 

Aglaia ponapensis 2,415,284 11,986 

Aidia cochinchinensis 203,862 

Allophylus timorensis 11,365 

Antidesma kusaiense 479,342 

Antidesma spp. 221,861 

Araucaria spp. 23,973 11,986 

Areca catechu 912,405 

Artocarpus altilis 1,976,825 30,954 15,477 252,569 

Averrhoa bilimbi 187,027 

Barringtonia asiatica 334,581 

Barringtonia racemosa 1,404,051 11,986 11,986 

Bruguiera gymnorrhiza 2,161,895 19,161 

Calophyllum inophyllum 41,341 22,730 9,306 

Campnosperma brevipetiolata 1,567,666 23,973 23,973 11,986 

Cananga odorata 4,614,388 223,744 11,986 11,986 208,267 

Carica papaya 10,207 

Cerbera manghas 17,810 

Cinnamomum carolinense 11,986 19,161 

Cinnamomum spp. 23,973 

Citrus reticulata 40,829 10,207 

Claoxylon carolinianum 459,919 

Cocos nucifera 630,735 30,622 

Commersonia bartramia 2,410,929 

Cyathea ponapeana 795,537 

Cyathea spp. 2,794,633 

Cycas spp. 53,431 

Cynometra ramiflora 11,986 

Dendrocnide harveyi 683,392 

Diospyros ferrea 115,917 

Elaeocarpus carolinensis 843,925 10,207 

Elaeocarpus kusanoi 471,906 

Eugenia spp. 508,509 

Eugenia stelechantha 6,173,861 221,861 

Exorrhiza ponapensis 5,070,993 76,643 

Fagraea berteriana 11,986 11,986 11,986 Ficus prolixa 313,588 17,810 275,292 

Ficus spp. 484,337 

Ficus tinctoria 745,406 9,306 

Garcinia ponapensis 19,161 

Garcinia rumiyo 143,833 

Glochidion spp. 1,418,169 141,568 15,477 

Heritiera littoralis 95,804 
42Table 10—Number of trees by primary damage type and species for all trees (continued)

No Broken	 Broken	 Broken	 	 Cracks/	 Damaged	 Loss of apical	 Open	 

Species	 damage	 bole	 or dead	 roots	 Conks	 seams	 foliage/shoots	 dominance	 wounds	 

Number of trees

Heterospathe elata 125,012 

Hibiscus tiliaceus 9,466,076 31,147 119,777 697,610 33,287 31,147 2,062,869 861,003 

Horsfieldia nunu 1,275,780 10,207 17,810 56,035 10,207 71,242 17,810 

Inocarpus fagifer 133,576 

Lumnitzera littorea 435,152 15,477 22,730 11,365 

Macaranga carolinensis 2,343,652 9,306 23,973 

Macaranga spp. 9,306 

Mangifera indica 504,667 15,477 164,788 

Morinda citrifolia 187,666 

Morinda spp. 115,917 

Musa nana 11,365 

Musa spp. 4,208,217 19,161 10,207 

Myristica insularis 1,086,235 

Neubergia celebica 356,741 

Palaquium karrak 11,986 

Pandanus cominsii 3,015,649 

Pandanus dubius 17,810 

Pandanus spp. 659,944 18,611 9,306 

Pandanus tectorius 435,412 11,365 34,094 11,365 115,917 

Pangium edule 329,103 

Parinari laurina 793,497 17,810 

Pittosporum spp. 43,133 

Ponapea hosinoi 221,229 

Ponapea ledermanniana 11,986 

Premna obtusifolia 684,735 9,306 10,207 11,365 11,365 Premna spp. 447,933 

Psychotria spp. 143,033 

Pterocarpus indicus 785,158 

Ptychococcus ledermanninus 35,621 

Rhizophora apiculata 826,325 11,365 

Rhizophora mucronata 862,236 

Rhizophora spp. 108,338 

Rhizophora stylosa 459,859 76,643 

Rhus taitensis 693,553 

Scyphiphora hydrophyllacea 1,415,679 11,365 22,730 

Semecarpus venenosus 274,111 9,306 9,306 46,528 

Sonneratia alba 672,933 106,011 19,161 Spathodea campanulata 2,581,794 11,986 11,986 322,595 35,959 

Sterculia palauensis 334,485 

Swietenia macrophylla 19,161 

Swietenia mahogoni 294,501 

Swietenia spp. 
43

Table 10—Number of trees by primary damage type and species for all trees (continued)

No Broken	 Broken	 Broken	 	 Cracks/	 Damaged	 Loss of apical	 Open	 

Species	 damage	 bole	 or dead	 roots	 Conks	 seams	 foliage/shoots	 dominance	 wounds	 

Number of trees

Syzygium carolinense 746,546 

Thespesia populnea 15,477 

Timonius spp. 243,820 19,161 

Toona ciliata 38,322 Trichospermum ikutai 27,917 

Unknown 2,874,152 15,477 19,161 9,306 

Unknown 0 57,482 

Unknown 14 115,917 

Unknown 20 125,222 

Unknown 5 141,568 Xylocarpus granatum 822,984 19,161 15,477 49,686 11,365 

 Total 83,456,594 128,229 389,347 27,116 1,523,451 309,802 232,025 3,614,946 1,389,585 
44

RESOURCE BULLETIN PNW-RB-262

Table 11—Estimated number of live trees ≥ 5 inches diameter at breast height on forest land by epiphyte 

loading (amounts of nontree vegetation in the canopy and branches) and species

Epiphyte loadings

Species	 None	 Low	 Moderate	 High	 All loadings

Number of trees

Adenanthera pavonina 53,431 189,807 234,478 61,305 539,022

Aglaia ponapensis 11,986 98,253 107,877 218,117

Aidia cochinchinensis 43,134 19,161 62,294

Allophylus timorensis 11,365 11,365

Antidesma kusaiense 17,810 17,810 35,621

Araucaria spp. 11,986 11,986 11,986 35,959

Areca catechu 170,471 34,094 204,566

Artocarpus altilis 121,685 249,366 176,202 128,186 675,439

Averrhoa bilimbi 34,094 11,365 45,459

Barringtonia asiatica 35,959 35,959

Barringtonia racemosa 41,986 56,373 82,125 47,945 228,431

Bruguiera gymnorrhiza 508,388 191,608 176,016 22,730 898,741

Calophyllum inophyllum 9,306 29,976 11,365 22,730 73,376

Campnosperma brevipetiolata 39,102 45,265 320,168 258,888 663,423

Cananga odorata 207,258 370,909 357,573 149,660 1,085,401

Carica papaya 10,207 10,207

Cerbera manghas 17,810 17,810

Cinnamomum carolinense 31,147 31,147

Cinnamomum spp. 11,986 11,986 23,973

Citrus reticulata 51,036 51,036

Claoxylon carolinianum 11,986 11,986

Cocos nucifera 227,340 244,556 158,820 108,850 739,566

Commersonia bartramia 71,918 56,629 32,657 11,986 173,190

Cyathea ponapeana 47,945 23,973 71,918 203,768 347,604

Cyathea spp. 17,810 315,688 668,778 207,475 1,209,752

Cycas spp. 35,621 17,810 53,431

Cynometra ramiflora 11,986 11,986

Dendrocnide harveyi 17,810 17,810 35,621

Elaeocarpus carolinensis 41,783 57,815 77,742 186,106 363,446

Elaeocarpus kusanoi 11,986 11,986 23,973

Eugenia spp. 19,161 23,351 42,512

Eugenia stelechantha 71,242 17,810 17,810 106,863

Exorrhiza ponapensis 346,109 1,546,325 1,758,589 810,000 4,461,023

Fagraea berteriana 11,986 23,973 35,959

Ficus prolixa 71,242 306,586 68,908 446,737

Ficus spp. 11,365 9,306 20,670

Ficus tinctoria 33,278 53,770 21,292 108,340

Garcinia ponapensis 19,161 19,161

Garcinia rumiyo 27,917 27,917

Glochidion spp. 15,477 65,041 51,624 11,986 144,128

Heritiera littoralis 38,322 57,482 95,804

Heterospathe elata 79,553 45,459 125,012

Hibiscus tiliaceus 262,995 845,490 762,305 691,109 2,561,899

Horsfieldia nunu 56,035 572,956 343,607 155,295 1,127,894

Inocarpus fagifer 56,933 68,847 19,161 144,941

Lumnitzera littorea 87,777 11,365 99,142

Macaranga carolinensis 32,657 9,306 128,580 63,422 233,964

Macaranga spp. 9,306 9,306

Mangifera indica 56,638 200,313 101,357 358,307

Morinda citrifolia 25,684 10,207 10,207 10,207 56,306
45

Federated States of Micronesia’s Forest Resources, 2006

Table 11—Estimated number of live trees ≥ 5 inches diameter at breast height on forest land by epiphyte 

loading (amounts of nontree vegetation in the canopy and branches) and species (continued)

Epiphyte loadings

Species	 None	 Low	 Moderate	 High	 All loadings

Number of trees

Musa nana 11,365 11,365

Musa spp. 1,530,285 343,051 226,286 92,597 2,192,218

Myristica insularis 86,267 246,902 155,823 488,991

Neubergia celebica 117,070 53,431 170,502

Palaquium karrak 11,986 11,986

Pandanus dubius 17,810 17,810

Pandanus spp. 74,444 9,306 58,350 18,611 160,711

Pandanus tectorius 107,470 11,365 118,835

Pangium edule 18,611 21,292 11,986 11,986 63,876

Parinari laurina 124,673 77,404 11,986 214,064

Pittosporum spp. 11,986 19,161 11,986 43,134

Ponapea hosinoi 11,986 23,973 35,959 71,918

Ponapea ledermanniana 11,986 11,986

Premna obtusifolia 11,365 29,976 57,183 11,986 110,510

Psychotria spp. 17,810 9,306 27,116

Pterocarpus indicus 55,120 68,919 63,876 187,915

Ptychococcus ledermanninus 35,621 35,621

Rhizophora apiculata 711,360 95,804 19,161 11,365 837,690

Rhizophora mucronata 728,110 114,965 19,161 862,236

Rhizophora spp. 108,338 108,338

Rhizophora stylosa 536,502 536,502

Rhus taitensis 11,365 11,365

Scyphiphora hydrophyllacea 34,094 34,094

Semecarpus venenosus 46,528 65,139 65,139 46,528 223,333

Sonneratia alba 201,815 166,001 95,804 95,804 559,424

Spathodea campanulata 323,632 203,768 47,945 575,345

Sterculia palauensis 76,643 19,161 95,804

Swietenia macrophylla 19,161 19,161

Swietenia mahogoni 11,365 11,365

Swietenia spp. 11,365 11,365

Syzygium carolinense 11,986 47,945 59,932

Thespesia populnea 15,477 15,477

Timonius spp. 31,147 31,147

Toona ciliata 19,161 19,161 38,322

Trichospermum ikutai 27,917 9,306 37,222

Unknown 55,736 49,565 101,550 34,088 240,939

Unknown 0 19,161 38,322 57,482

Unknown 20 9,306 9,306

Xylocarpus granatum 629,363 22,730 125,012 777,105

 Total 7,669,235 7,230,917 7,815,005 4,520,136 27,235,293
46

RESOURCE BULLETIN PNW-RB-262

Forest Dynamics

The forests of the FSM are generally dense forests with larger trees, reflected in 

high basal area and wood volume on a per-acre basis (table 12). Gap-phase dynamics typically characterize tropical forests where little human intervention occurs 

(Brokaw 1985). Species die and are replaced on an individual basis as the forest 

renews itself. In more heavily disturbed areas, cohorts of regeneration, maturity, 

and senescence are common. Forest structure and species composition change 

through time as a result of forest succession and disturbance dynamics. The forests 

of the FSM have been strongly influenced by a long history of shifting human 

settlement and disturbance, both human caused and climatic. Human populations 

have fluctuated, and resulting land use has changed. Within the last century, the 

most important land use changes have involved the conversion of forests to agricultural and urban uses, and disturbance by military actions, especially on Chuuk. 

Table 12—Estimated number of trees per acre, basal area per acre, net and gross volume per acre, and 

standard errors (SE) for trees ≥5 inches, 2005–2006

Chuuk	 SE	 Kosrae	 SE	 Pohnpei	 SE	 Yap	 SE	 Total	 SE

Trees per acre 137 21 166 29 208 18 123 20 179 12

Basal area (ft2 per acre) 98 21 142 38 158 16 51 12 132 12

Net volume (ft3 per acre) 2,411 813 4,357 1,397 4,582 552 1,026 334 3,752 417

Gross volume (ft3 per acre) 2,423 815 4,358 1,398 4,645 564 1,027 334 3,788 422

Much of the flat land on Chuuk had been planted with coconut (Cocos nucifiera

L.) and sweet potato (Ipomoea batatas (L.) Lam.) prior to and during World War II 

and now supports agroforest (Mueller-Dombois and Fosberg 1998). Yap has had a 

long history of agroforestry use in the form of tree gardens that supported formerly 

extensive human populations (Mueller-Dombois and Fosberg 1998). Much of the 

native vegetation there has been altered. Pohnpei’s intact upland forest is currently 

threatened by commercial introductions of kava. A “Grow Low” campaign sponsored by the Conservation Society of Pohnpei and The Nature Conservancy seeks 

to conserve intact upland forests by promoting the cultivation of agricultural crops 

at lower elevations. The interpretation of 1975 aerial photography showed Pohnpei 

to be about 16 percent agroforest, but that percentage was adjusted upward to 33 

percent using the proportion of field plots found to be agroforest in 1983 (MacLean 

et al. 1986). From the mapping work in 2005–2006, Pohnpei’s agroforest was 
47

Federated States of Micronesia’s Forest Resources, 2006

estimated to be about 16 percent of total land cover (table 2). Using the 2006 inventory plots, the inventory-based estimate for agroforest area would be only about 9 

percent of total land cover. However, the standard error of the field-plot estimate is 

about 45 percent of the estimate meaning the percentage of agroforest is 9 percent, 

plus or minus 4.5 percent. On Kosrae, the abundance of precipitation and the 

difficulty in access to the steep topography has permitted the persistence of dense 

upland rain forest with tremendous epiphyte growth. In the lowlands, the landscape 

has been modified to provide food and fiber via agroforest. However, as sea levels 

rise, Kosrae is faced with the possibility of substantial loss of flat, lowland areas 

owing to tidal surges and inundation. Food and water security have become important concerns for low-lying Pacific islands and atolls that are facing the loss 

of arable lands, both through urbanization and inundation from rising sea levels.

Acknowledgments

The FIA Pacific Island inventories are the result of cooperative effort between a 

number of groups and agencies. Foremost, the help and expertise of local island 

foresters and ecologists made the data collection and plant identification efforts 

possible; sincere thanks to Margie Falanruw, Pong Chingyan, Nixon Daniel, 

Rosando Frederik, Tarita Holm, Marciano Imar, Killion Isisaki, Carlos Kufen, 

Henry Layirang, Epipanio Lengsi, Simon Lihpai, Roseo Marquez, Falaniko Mika, 

Larko Mikel, Longona Misa, David Palacios, Walter Peter, D.J. Primo, Francis 

Ruegorong, Valentine Santiago, Sleeper Sared, John Silbanuz, Simon Stowers, 

Raphaella Tinngian, and Eric Waguk. The USDA Forest Service, State and Private 

Forestry in the Pacific Southwest Region has been a strong supporter of natural 

resource assessments in the Pacific Islands. Many thanks to the Pacific Islands 

Imagery Consortium partners for sharing costs on imagery and interpretation. 

Thanks to Tim Flynn and David Lorence at the National Tropical Botanical Garden 

and staff at the Bishop Museum for species identification and training; Lisa Fischer 

and Zhafeng Liu (Leo) at the Remote Sensing Lab in the Pacific Southwest Region. 

We also thank Dale Weyermann, John Chase, and Chuck Veneklase with FIA for 

work in geographic information systems, programming, and technical support. 

Dave Azuma, Tom Brandeis, and Margie Falanruw offered very helpful comments 

on prior drafts.
48

RESOURCE BULLETIN PNW-RB-262

Metric Equivalents

When you know:	 Multiply by:	 To find:

Inches 2.54 Centimeters

Feet .305 Meters

Miles 1.609 Kilometers

Acres .405 Hectares

Square miles 2.59 Square kilometers

Cubic feet .028 Cubic meters

Tons 907 Kilograms

Tons per acre 2.24 Tonnes or megagrams per hectare

Cubic feet per acre .07 Cubic meters per hectare

Trees per acre 2.471 Trees per hectare

Degrees Fahrenheit (°F – 32)/1.8 Degrees Celsius

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