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Ecological site QX191X01X504

Limestone Plateau Cloud Forest

Last updated: 6/04/2025
Accessed: 12/06/2025

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General information

Provisional. A provisional ecological site description has undergone quality control and quality assurance review. It contains a working state and transition model and enough information to identify the ecological site.

MLRA notes

Major Land Resource Area (MLRA): 191X–High Limestone Plateaus of the Mariana Islands

This MLRA consists of the northern half of Guam and the islands of Saipan), Tinian, Rota, and Aguijan. Topography consists mostly of limestone plateaus. The highest elevations are 1,700 feet (520 meters) on Rota, 1,485 feet (450 meters) on Saipan, 655 feet (200 meters) on Tinian, and 860 feet (260 meters) in the northern part of Guam. The limestone plateaus were uplifted by tectonic activity. Deeply weathered volcanic rock is exposed on some ridges and slopes. Average annual rainfall is 100 inches (2,540 millimeters) on northern Guam and 80 inches (2,030 millimeters) on Saipan, Tinian, Aguijan, and Rota. The rainy season occurs from July through November; the dry season occurs from December through June. Trade winds blow from the northeast. Average annual temperature is 79 degrees F (26 degrees C). Typhoons are frequent. Soils are Alfisols, Andisols, Entisols, Mollisols, or Oxisols. The dominant soil moisture regime is ustic. The soil temperature regime is isohyperthermic. Native vegetation consists of mixed tropical hardwoods; introduced white leadtree or tangantangan trees are abundant. Introduced deer, pigs, goats, and water buffalo are common (USDA-NRCS, 2006). The main human disturbance is clearing land for cultivation. Feral pigs, feral cattle, brown tree snakes, stray dogs (Boonie dogs), and introduced deer are destructive to the native forest (Amand, 2000; CNMI SWARS Council, 2010; Donnegan et al., 2011; Liske-Clark, 2015; Willsey et al., 2019).

Classification relationships

This ecological site occurs within Major Land Resource Area (MLRA) 191 – High Limestone Plateaus of the Mariana Islands.

Ecological site concept

This ecological site occurs on the island of Rota in the Marianas Islands. It occurs on nearly level to modserately sloping (0 to 15 percent slopes) limestone plateaus at elevations ranging from 1,310 to 1570 feet (400 to 480 meters) (USDA-SCS, 1989).

Soils are shallow, well drained Entisols (lithic ustorthents) in “moist” phases of Luta series that formed in sediment over porous coralline limestone. Soil temperature regimes are isohyperthermic; soil moisture regimes are ustic. Average annual precipitation is 116 inches (2,945 millimeters) and ranges from 113 to 120 inches (2,870 to 3,050 millimeters) (PRISM, 2006). The area is often shrouded in clouds and fog. Water runoff is very low or low; permeability is moderately rapid. Effective rooting depth is 10 to 16 inches (25 to 40 cm). Available water-holding capacity is very low (1 inch) (USDA-SCS, 1989). Most of the area is vegetated by native forest (Amidon et al., 2017; Falanruw et al., 1989; Fosberg, 1960; Liu and Fischer, 2008; Stone, 1970; Wagner and Grether, 1948; Willsey et al., 2019).

Associated sites

QX191X01X505	Very Low Available Water Capacity Soils on Limestone Plateaus and Escarpments Soils of QX191X01X505 (The Very Low Available Water Capacity Soils on Limestone Plateaus and Escarpments Ecological Site) formed in porous coralline limestone. Effective rooting depth is 2 to 16 inches; available water holding capacity is very low (1). Most of the area is vegetated by native forest. Soils of Q191X01X504 (The Limestone Plateau Cloud Forest Ecological Site) formed in limestone. Effective rooting depth is 10 to 16 inches and available water holding capacity is also very low (1). Most of the area is vegetated by native forest. Moisture is added to the soil by fog drip, which maintains moist soils.
QX191X01X002	Moderately Deep Alfic Soils on Volcanic Uplands Soils of QX191X01X002 (The Moderately Deep Alfic Soils on Volcanic Uplands Ecological Site) formed in residuum derived from andesitic marine tuff and tuffaceous breccia. They are highly weathered Alfisols that have fairly high base saturation, effective rooting depths of approximately 32 inches, surface pH of 6.2 to 6.5, and low available water holding capacity (4 inches). Most of the area is vegetated by grasses, forbs, and mixed forest of introduced and native species. Pacific Island silvergrass or swordgrass (Miscanthus floridulus) is present in some areas. white lead tree or tangantangan (Leucaena leucocephala) is not abundant. Soils of Q191X01X504 (The Limestone Plateau Cloud Forest Ecological Site) formed in fine materials over porous coralline limestone. Effective rooting depth is about 12 inches, surface pH of 7.0 to 7.2; available water holding capacity is very low (1 inch). Most of the area is vegetated by native forest. This ecological site is limited to an area that is often shrouded in clouds and fog. Moisture is added to the soil by fog drip, which maintains the soils in moist condition most of the time.
QX191X01X503	Very Shallow to Moderately Deep Soils on Limestone Plateaus Soils of QX191X01X503 (The Very Shallow to Moderately Deep Soils on Limestone Plateaus Ecological Site) formed in fine materials over porous coralline or argillaceous limestone. Effective rooting depth is 2 to 20 inches and available water holding capacity is very low to low (2 to 3 inches). Areas not farmed are vegetated by mostly introduced grass, forb, and tree species, with some areas of native upland forest. Tangantangan (Leucaena leucocephala) is abundant in places. Soils of Q191X01X504 (The Limestone Plateau Cloud Forest Ecological Site) formed in fine materials over porous coralline limestone. Effective rooting depth is about 12 inches, surface pH of 7.0 to 7.2; available water holding capacity is very low (1 inch). Most of the area is vegetated by native forest. This ecological site is limited to an area that is often shrouded in clouds and fog. Moisture is added to the soil by fog drip, which maintains the soils in moist condition most of the time.

QX191X01X505

Very Low Available Water Capacity Soils on Limestone Plateaus and Escarpments

Soils of QX191X01X505 (The Very Low Available Water Capacity Soils on Limestone Plateaus and Escarpments Ecological Site) formed in porous coralline limestone. Effective rooting depth is 2 to 16 inches; available water holding capacity is very low (1). Most of the area is vegetated by native forest. Soils of Q191X01X504 (The Limestone Plateau Cloud Forest Ecological Site) formed in limestone. Effective rooting depth is 10 to 16 inches and available water holding capacity is also very low (1). Most of the area is vegetated by native forest. Moisture is added to the soil by fog drip, which maintains moist soils.

QX191X01X002

Moderately Deep Alfic Soils on Volcanic Uplands

Soils of QX191X01X002 (The Moderately Deep Alfic Soils on Volcanic Uplands Ecological Site) formed in residuum derived from andesitic marine tuff and tuffaceous breccia. They are highly weathered Alfisols that have fairly high base saturation, effective rooting depths of approximately 32 inches, surface pH of 6.2 to 6.5, and low available water holding capacity (4 inches). Most of the area is vegetated by grasses, forbs, and mixed forest of introduced and native species. Pacific Island silvergrass or swordgrass (Miscanthus floridulus) is present in some areas. white lead tree or tangantangan (Leucaena leucocephala) is not abundant. Soils of Q191X01X504 (The Limestone Plateau Cloud Forest Ecological Site) formed in fine materials over porous coralline limestone. Effective rooting depth is about 12 inches, surface pH of 7.0 to 7.2; available water holding capacity is very low (1 inch). Most of the area is vegetated by native forest. This ecological site is limited to an area that is often shrouded in clouds and fog. Moisture is added to the soil by fog drip, which maintains the soils in moist condition most of the time.

QX191X01X503

Very Shallow to Moderately Deep Soils on Limestone Plateaus

Soils of QX191X01X503 (The Very Shallow to Moderately Deep Soils on Limestone Plateaus Ecological Site) formed in fine materials over porous coralline or argillaceous limestone. Effective rooting depth is 2 to 20 inches and available water holding capacity is very low to low (2 to 3 inches). Areas not farmed are vegetated by mostly introduced grass, forb, and tree species, with some areas of native upland forest. Tangantangan (Leucaena leucocephala) is abundant in places. Soils of Q191X01X504 (The Limestone Plateau Cloud Forest Ecological Site) formed in fine materials over porous coralline limestone. Effective rooting depth is about 12 inches, surface pH of 7.0 to 7.2; available water holding capacity is very low (1 inch). Most of the area is vegetated by native forest. This ecological site is limited to an area that is often shrouded in clouds and fog. Moisture is added to the soil by fog drip, which maintains the soils in moist condition most of the time.

Table 1. Dominant plant species

Tree	(1) Hernandia labyrinthica (2) Elaeocarpus joga
Shrub	(1) Freycinetia reineckei
Herbaceous	Not specified

Legacy ID

F191XY504MP

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Physiographic features

This ecological site occurs on limestone plateaus (USDA-SCS, 1989). The depth to the water table is greater than 72 inches (183 centimeters).

Table 2. Representative physiographic features

Landforms	(1) Plateau
Runoff class	Very low to low
Flooding frequency	None
Ponding frequency	None
Elevation	1,310 – 1,570 ft
Slope	15%
Water table depth	72 in
Aspect	Aspect is not a significant factor

Climatic features

Summary for this Ecological Site

Rainfall statistics were determined from PRISM rainfall raster data (PRISM, 2006). Representative (20th and 80th percentiles) values for mean annual precipitation range from 113 to 120 inches (2,870 to 3,050 millimeters) while actual (10th and 90th percentiles) values for mean annual precipitation range from 105 to 121 inches (2,675 to 3,070 millimeters). Extreme values range from 77 to 122 inches (1,955 to 3,100 millimeters). The average annual precipitation is 116 inches (2,945 millimeters) and the median annual average precipitation is 119 inches (3,020 millimeters).

Temperature statistics were determined from PRISM temperature raster data (PRISM, 2006) Representative (20th and 80th percentiles) values for mean annual temperatures is about 75 degrees F (24 degrees C) while actual (10th and 90th percentiles) values for mean annual temperatures are also about 75 degrees F (24 degrees C). Extreme values range from 75 to 79 degrees F (24 to 26 degrees C). The average annual temperature is 75 degrees F (24 degrees C), and the median annual temperature is also 75 degrees F (24 degrees C).

No suitable climate stations are available that are representative of this ecological site. As such the data presented in the climate normals tables below are from the PRISM data above.

General Principles

The climate is uniformly warm and humid throughout the year. Afternoon temperatures typically are about 86 degrees F (30 degrees C); nighttime temperatures are about 68 degrees F (20 degrees C). Relative humidity is 65 to 75 percent in the afternoon to 85 to 100 percent at night. Though temperature and humidity vary only slightly throughout the year, rainfall and wind conditions vary markedly. There are two main seasons, the dry season from December through June and the rainy season from mid-July to mid-November. Moisture deficit occurs between January and June. Mean annual rainfall ranges from about 98 inches (2,490 millimeters) on the windward (eastern) side of the higher mountains to about 79 inches (2,005 millimeters) along the coast of the western side of the islands. On average, about 15 percent of the annual rainfall occurs during the dry season and 55 percent during the rainy season (Fosberg, 1960; USDA-SCS, 1988; USDA-SCS, 1989).

Throughout the year, the dominant winds are the trade winds that blow from the east or northeast. The trade winds are strongest and most constant during the dry season, when windspeeds of 15 to 25 mph (25 to 40 kph) are common. Coastal areas that have east, and northeast exposures are subject to salt spray and buffeting winds (Fosberg, 1960; USDA-SCS, 1988; USDA-SCS, 1989).

During the rainy season the trade winds may break down and be replaced by a weak, westerly monsoon influence that brings heavy showers or steady and sometimes torrential rains. The islands lie in the path of typhoons from the southeast and east. They bring heavy rains and violent winds that may result in a surge of water onto low-lying coastal areas. They occur most frequently during the latter half of the year. The chance of having one or more typhoons pass close to the islands in any particular year is about once in three years. The chance of having a typhoon move directly across an island is about once in eight years (Fosberg, 1960; USDA-SCS, 1988; USDA-SCS, 1989).

Table 3. Representative climatic features

Frost-free period (characteristic range)	365 days
Freeze-free period (characteristic range)	365 days
Precipitation total (characteristic range)	113-120 in
Frost-free period (actual range)	365 days
Freeze-free period (actual range)	365 days
Precipitation total (actual range)	105-121 in
Frost-free period (average)	365 days
Freeze-free period (average)	365 days
Precipitation total (average)	116 in

Soil features

A moist phase of one soil component is associated with this ecological site; Luta (Entisols) (USDA-SCS, 1988; USDA-SCS, 1989). Soil temperature regimes are isohyperthermic; soil moisture regimes are ustic. They are shallow and well drained. The underlying coralline limestone is porous (USDA-SCS, 1989).

Table 4. Representative soil features

Parent material	(1) Limestone
Surface texture	(1) Cobbly clay loam
Family particle size	(1) Loamy
Drainage class	Well drained
Permeability class	Moderate
Depth to restrictive layer	10 – 16 in
Soil depth	10 – 16 in
Surface fragment cover <=3"	Not specified
Surface fragment cover >3"	15%
Available water capacity (0-40in)	1 in
Calcium carbonate equivalent (0-40in)	Not specified
Electrical conductivity (0-40in)	Not specified
Sodium adsorption ratio (0-40in)	Not specified
Soil reaction (1:1 water) (0-10in)	7 – 7.2
Subsurface fragment volume <=3" (0-40in)	8%
Subsurface fragment volume >3" (0-40in)	13%

Ecological dynamics

The main human disturbance was phosphate mining. Feral pigs, feral cattle, and introduced deer are destructive to the forest (CNMI SWARS Council, 2010; Donnegan et al., 2011; Liske-Clark, 2015; Willsey et al., 2019).

The main natural disturbance is strong storms that can damage or kill vegetation by high wind speeds. Natural fire is rare in forested areas due to the low amounts of fine fuels on the ground (CNMI SWARS Council, 2010; Donnegan et al., 2011; Liske-Clark, 2015; Willsey et al., 2019).

State and transition model

Custom diagram

Standard diagram

Figure 1. State-and-Transition Model for F191XY504MP (The Limestone Plateau Cloud Forest Ecological Site).

More interactive model formats are also available. View Interactive Models

More interactive model formats are also available. View Interactive Models
Click on state and transition labels to scroll to the respective text

Ecosystem states

1. Reference State

2. Naturalized Grassland State

3. Cleared and Abandoned State

4. Grazed Woodland State

T1A	-	The Reference State (1) may transition to the Naturalized Grassland State (2) by mechanical clearing of the land followed by invasion by or planting of introduced forage species.
T1B	-	The Reference State (1) may transition to the Cleared and Abandoned State (3) by clearing the forest, temporary cultivation of crops, abandonment, and invasion by mostly introduced species.
R2A	-	The Naturalized Grassland State (2) can be restored to a facsimile of the Reference State (1) by suppressing the forage species and replanting native trees.
T2A	-	The Naturalized Grassland State (2) will transition to the Cleared and Abandoned State (3) from community phase 2.1 if the forage species are reduced in cover and vitality by heavy grazing before abandonment, allowing invasion of the site by weedy shrub, forb, and vine species.
R3B	-	The Cleared and Abandoned State (3) can be restored to a facsimile of the Reference State (1) by brush and weed control followed by replanting of native trees.
R3A	-	The Cleared and Abandoned State (3) may be restored to the Naturalized Grassland State (2) by brush control, weed control, reseeding of desired forage species, and cutting back white leadtree to a shorter stature.
T3A	-	The Cleared and Abandoned State (3) will transition to the Grazed Woodland State (4) by continued growth and spread of small Philippine acacia, possible invasion by other tree species, and closure of the overstory to shade out most shrubs, forbs, and grasses.
R4A	-	The Grazed Woodland State (4) may be restored to a facsimile of the Reference State (1) by brush and weed control followed by replanting of native trees.
R4B	-	The Grazed Woodland State (4) may be restored to the Cleared and Abandoned State (3) by clearing and abandoning the site, allowing lower-growing species that require sunlight to invade.

State 1 submodel, plant communities

1.1. Hernandia – Yogga/Freycinetia

1.2. Tahitian Screwpine – Sea Hibiscus/Freycinetia

1.1A	-	Community phase 1.1 may shift to phase 1.2 by damage from powerful storms.
1.2A	-	Community phase 1.2 reverts to phase 1.1 by regrowth of the original dominant species if given enough time between strong storm events. Browsing and grazing by introduced ungulates may inhibit this process by destruction of tree seedlings.

State 2 submodel, plant communities

2.1. Guineagrass – Elephant Grass

2.2. Guineagrass – Mission Grass/Balsampear

2.1A	-	Community phase 2.1 will shift to phase 2.2 by overgrazing, which allows invasion by unpalatable grass and forb species.
2.2A	-	Community phase 2.2 will revert to phase 2.1 with properly managed grazing, which allows desirable species to gradually regain dominance, and possible spot weed control.

State 3 submodel, plant communities

3.1. Small Philippine Acacia/Old World Forkedfern

State 4 submodel, plant communities

4.1. Small Philippine Acacia – Woman’s Tongue/Guineagrass – Mission grass

State 1
Reference State

The Reference State (1) has two community phases both consisting of a diverse native forest.

Community 1.1
Hernandia – Yogga/Freycinetia

Dominant canopy species are Elaeocarpus or yogga (Elaeocarpus joga), Hernandia (Hernandia labyrinthica), chelilai (Fagraea berteroana var. galilai), screwpine (Pandanus spp.), Pacific banyan (Ficus prolixa var. prolixa), fig (F. tinctoria), artocarpus (Artocarpus mariannensis), Pipturus argenteus, Guamia mariannae, and umbrella catchbirdtree (Pisonia umbellifera). Shrubs and many ferns inhabit the undergrowth. Freycinetia reineckei and alyxia (Alyxia spp.) are common lianas. A liana is a long-stemmed woody vine that is rooted in the soil at ground level and uses trees, as well as other means of vertical support, to climb up to the canopy in search of direct sunlight. Epiphytic ferns and orchids are abundant (Amidon et al., 2017; Falanruw et al., 1989; Fosberg, 1960; Liu and Fischer, 2008; Stone, 1970; Wagner and Grether, 1948; Willsey et al., 2019).

Dominant plant species

Community 1.2
Tahitian Screwpine – Sea Hibiscus/Freycinetia

Storm damage to dominant overstory trees allows fast-growing or abundant subdominant species to temporarily become more abundant. Some typical species include Tahitian screwpine (Pandanus tectorius), sea hibiscus (Hibiscus tiliaceus), and Freycinetia reineckei (CNMI SWARS Council, 2010; Donnegan et al., 2011; Liske-Clark, 2015; Willsey et al., 2019).

Dominant plant species

Tahitian screwpine (Pandanus tectorius), tree
sea hibiscus (Hibiscus tiliaceus), tree
(Freycinetia reineckei), shrub

Pathway 1.1A
Community 1.1 to 1.2

Community phase 1.1 may shift to phase 1.2 by damage from powerful storms.

Pathway 1.2A
Community 1.2 to 1.1

Community phase 1.2 reverts to phase 1.1 by regrowth of the original dominant species if given enough time between strong storm events. Browsing and grazing by introduced ungulates may inhibit this process by destruction of tree seedlings.

State 2
Naturalized Grassland State

The Naturalized Grassland State (2) consists of two community phases consisting mostly of introduced grass species.

Community 2.1
Guineagrass – Elephant Grass

Guineagrass (Urochloa maxima) is the main grass species; elephant grass (Pennisetum purpureum) may also be abundant. These large grasses are very competitive, excluding many other species. Some leguminous forbs may be present, including calopo (Calopogonium mucunoides), flor de conchitas or centre (Centrosema pubescens), Sarawak bean (Vigna hosei Syn. Dolichos hosei), bonavist-bean or lablab (Lablab purpureus ssp. purpureus Syn. Dolichos lablab), Hawai'i ticktrefoil (Desmodium sandwicense Syn. D. uncinatum), and greenleaf ticktrefoil (D. intortum) (CNMI SWARS Council, 2010; Donnegan et al., 2011; Liske-Clark, 2015; Willsey et al., 2019).

Dominant plant species

guineagrass (Urochloa maxima), grass
elephant grass (Pennisetum purpureum), grass

Community 2.2
Guineagrass – Mission Grass/Balsampear

Guineagrass (Urochloa maxima) is still common but has been heavily grazed, leaving openings for other species such as mission grass (Pennisetum polystachion) to invade the site. Unpalatable forbs such as balsampear (Momordica charantia) are common. Other possible common, but not abundant, species are romerillo (Bidens alba), scaly swordfern (Nephrolepis hirsutula), Philippine ground orchid (Spathoglottis plicata), monarch fern (Phymatosorus scolopendria), climbing hempvine (Mikania scandens), Jack in the bush (Chromolaena odorata), and Canadian horseweed (Conyza canadensis) (CNMI SWARS Council, 2010; Donnegan et al., 2011; Liske-Clark, 2015; Willsey et al., 2019).

Dominant plant species

guineagrass (Urochloa maxima), grass
mission grass (Pennisetum polystachion), grass
balsampear (Momordica charantia), other herbaceous

Pathway 2.1A
Community 2.1 to 2.2

Community phase 2.1 will shift to phase 2.2 by overgrazing, which allows invasion by unpalatable grass and forb species.

Pathway 2.2A
Community 2.2 to 2.1

Community phase 2.2 will revert to phase 2.1 with properly managed grazing, which allows desirable species to gradually regain dominance, and possible spot weed control.

State 3
Cleared and Abandoned State

The Cleared and Abandoned State (3) consists of one community phase dominated by weedy, mostly introduced species.

Community 3.1
Small Philippine Acacia/Old World Forkedfern

Common species in this community phase are small Philippine acacia (Acacia confusa) and Old World forkedfern (Dicranopteris linearis). Guineagrass (Urochloa maxima) is still present in patches. Other abundant species may be mission grass (Pennisetum polystachion), giant false sensitive plant (Mimosa diplotricha), scaly swordfern (Nephrolepis hirsutula), Philippine ground orchid (Spathoglottis plicata), monarch fern (Phymatosorus scolopendria), climbing hempvine (Mikania scandens), Jack in the bush (Chromolaena odorata), and Canadian horseweed (Conyza canadensis) (CNMI SWARS Council, 2010; Donnegan et al., 2011; Liske-Clark, 2015; Willsey et al., 2019).

Dominant plant species

small Philippine acacia (Acacia confusa), tree
Old World forkedfern (Dicranopteris linearis), shrub

State 4
Grazed Woodland State

The Grazed Woodland State (4) consists of a variable mix of introduced tree species, sometimes with a few native species, that form a dense forest. Small Philippine acacia (Acacia confusa) may dominate, or other tree species may gradually invade a site. Cattle may forage in these forests, but carrying capacity is low (CNMI SWARS Council, 2010; Donnegan et al., 2011; Liske-Clark, 2015; Willsey et al., 2019).

Community 4.1
Small Philippine Acacia – Woman’s Tongue/Guineagrass – Mission grass

Small Philippine acacia (Acacia confusa) is often dominant, along with woman’s tongue (Albizia lebbeck). Other common introduced tree species are royal poinciana (Delonix regia) and African tulip tree (Spathodea campanulata). Possible native species are Guamia mariannae, Melanolepis multiglandulosa, and wild coffee (Psychotria spp). Invasive vines such as Jack in the bush (Chromolaena odorata) are likely to be present. Guineagrass (Urochloa maxima) and mission grass (Pennisetum polystachion) persist in sunny openings (CNMI SWARS Council, 2010; Donnegan et al., 2011; Liske-Clark, 2015; Willsey et al., 2019).

Dominant plant species

small Philippine acacia (Acacia confusa), tree
woman's tongue (Albizia lebbeck), tree
guineagrass (Urochloa maxima), grass
mission grass (Pennisetum polystachion), grass

Transition T1A
State 1 to 2

The Reference State (1) may transition to the Naturalized Grassland State (2) by mechanical clearing of the land followed by invasion by or planting of introduced forage species.

Transition T1B
State 1 to 3

The Reference State (1) may transition to the Cleared and Abandoned State (3) by clearing the forest, temporary cultivation of crops, abandonment, and invasion by mostly introduced species.

Restoration pathway R2A
State 2 to 1

The Naturalized Grassland State (2) can be restored to a facsimile of the Reference State (1) by suppressing the forage species and replanting native trees.

Transition T2A
State 2 to 3

The Naturalized Grassland State (2) will transition to the Cleared and Abandoned State (3) from community phase 2.1 if the forage species are reduced in cover and vitality by heavy grazing before abandonment, allowing invasion of the site by weedy shrub, forb, and vine species.

Restoration pathway R3B
State 3 to 1

The Cleared and Abandoned State (3) can be restored to a facsimile of the Reference State (1) by brush and weed control followed by replanting of native trees.

Restoration pathway R3A
State 3 to 2

The Cleared and Abandoned State (3) may be restored to the Naturalized Grassland State (2) by brush control, weed control, reseeding of desired forage species, and cutting back white leadtree to a shorter stature.

Transition T3A
State 3 to 4

The Cleared and Abandoned State (3) will transition to the Grazed Woodland State (4) by continued growth and spread of small Philippine acacia, possible invasion by other tree species, and closure of the overstory to shade out most shrubs, forbs, and grasses.

Restoration pathway R4A
State 4 to 1

The Grazed Woodland State (4) may be restored to a facsimile of the Reference State (1) by brush and weed control followed by replanting of native trees.

Restoration pathway R4B
State 4 to 3

The Grazed Woodland State (4) may be restored to the Cleared and Abandoned State (3) by clearing and abandoning the site, allowing lower-growing species that require sunlight to invade.

Additional community tables

Supporting information

Other references

References for QX191X01X504 (The Very Shallow to Moderately Deep Soils on Limestone Plateaus Ecological Site).

Amand, A. (2000). Boiga irregularis (Brown Tree Snake) on Guam and Its Effect on Fauna. Restoration and Reclamation Review, 6 1-6.

Amidon, F., Metevier, M., and Miller, S. E. (2017). Vegetation Mapping of the Mariana Islands: Commonwealth of the Northern Mariana Islands and Territory of Guam. US Fish and Wildlife Service and Pacific Islands Climate Change Cooperative. Final Report November 2017.

CNMI SWARS Council. (2010). Commonwealth of the Northern Mariana Islands (CNMI) Statewide Assessment and Resource Strategy 2010-2015+. CNMI Forestry.

Donnegan, J. A., Butler, S. L., Kuegler, O., Hiserote, B. A. (2011). Commonwealth of the Northern Mariana Islands’ Forest resources, 2004. Resource. Bull. PNW-RB-261. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 40 p.

Falanruw, M. C., Cole, T. G., Ambacher, A. H. (1989). Vegetation survey of Rota, Tinian, and Saipan, Commonwealth of the Northern Mariana Islands. Resource. Bull. PSW-27. Berkeley, CA: Pacific Southwest Forest and Range Experiment Station, Forest Service, U.S. Department of Agriculture.

Fosberg, F. R. (1960). The Vegetation of Micronesia. I. General descriptions, the vegetation of the Marianas Islands, and a detailed consideration of the vegetation of Guam. Bulletin of the American Museum of Natural History 199:1.

Liske-Clark, J. (2015). Wildlife Action Plan for the Commonwealth of the Northern Mariana Islands, 2015-2025. CNMI DLRN-Division of Fish and Wildlife, Saipan, MP.

Liu, Z. and Fischer, L. (2008). Commonwealth of the Northern Mariana Islands Vegetation Mapping Using Very High Spatial Resolution Imagery. USDA Forest Service Pacific Southwest Region, Forest Health Protection, McClellan, CA.

PRISM Climate Group, Oregon State University. (2006). https://prism.oregonstate.edu, data created 4 Feb 2014, accessed 09 Oct 2024. Pacific Islands Project: Average monthly precipitation, minimum and maximum temperature, relative humidity, and mean dew point temperature for the period 1971-2000 (completed 2006). Covers Hawaii, Kosrae, Manua, Pohnpei, Tutuila, Guam, CNMI, and Palau. Project sponsored by USDA Natural Resources Conservation Service.

Stone, B. C. (1970). The Flora of Guam. A Manual for the Identification of the Vascular Plants of the Island. Micronesica – Journal of the University of Guam, vol. 6, July 1970.

USDA-NRCS. (2006). Major Land Resource Regions. USDA Agriculture Handbook 296. http://soils.usda.gov/MLRAExplorer

USDA-Soil Conservation Service. (1989). Soil Survey of the Islands of Aguijan, Rota, Saipan, and Tinian, Commonwealth of the Northern Mariana Islands.

USDA-Soil Conservation Service. (1988). Soil Survey of Territory of Guam.

Wagner, W. H. and Grether, D. F. (1948). The Pteridophytes of Guam. Occasional Papers of Bernice P. Bishop Museum, volume XIX, number 2. Honolulu, Hawaii.

U. S. Department of Interior, Fish & Wildlife Service. (2023). Download seamless wetlands data by state. National Wetlands Inventory website. U.S. Department of the Interior, Fish and Wildlife Service, Washington, D.C. Accessed April 24, 2024. [https://www.fws.gov/program/national-wetlands-inventory/download-state-wetlands-data].

Willsey, T., Kwon, J. A., Reeves, M. K., Amidon, F., and Miller, S. E. (2019). Mariana Islands Forest. Encyclopedia of the World's Biomes. https://doi.org/10.1016\B978-0-12-409548-9.12012-3

Contributors

David Clausnitzer PhD
John Proctor
Ann Tan
Daniel Bowman
Amy Koch
Kendra Moseley
Sarah Quistberg
Brandan Brazee
Daniel Block
Jill Fick-Beaton

Approval

Curtis Talbot, 6/04/2025

Acknowledgments

Assistance, advice, review, and/or insights:

Michael Constantinides, NRCS-PIA
Jennifer Higashino, USFWS and NRCS
Mike Kolman, NRCS
Bart Lawrence, NRCS
Pamela Sablan, NRCS

Rangeland health reference sheet

Interpreting Indicators of Rangeland Health is a qualitative assessment protocol used to determine ecosystem condition based on benchmark characteristics described in the Reference Sheet. A suite of 17 (or more) indicators are typically considered in an assessment. The ecological site(s) representative of an assessment location must be known prior to applying the protocol and must be verified based on soils and climate. Current plant community cannot be used to identify the ecological site.

Author(s)/participant(s)
Contact for lead author
Date	06/04/2025
Approved by	Curtis Talbot
Approval date
Composition (Indicators 10 and 12) based on	Annual Production