Ecological site VX165X01X001

4. Shrub Invaded Grassland State

3. Native Forest State

States 1, 5 and 2 (additional transitions)

1.1. Koa haole (white leadtree)/kikuyugrass-guineagrass

R1A	-	It is possible to restore State 1 Reference to a plant community resembling State 3 Native Forest. Weed control must be applied to forage species and the many opportunistic plant species that would invade the site. Weed control would be a perpetual process to maintain the site. Fire must be excluded. Domestic and feral ungulates must be excluded by a suitably designed and maintained fence. Extensive planting of native species would follow.
T1A	-	State 1 Reference transitions to State 4 Shrub Invaded Grassland through further overgrazing or abandonment. Fire will temporarily prevent this transition. Koa haole will be greatly reduced by over browsing. If the site contained abundant koa haole and was then abandoned, these small trees can greatly increase in abundance. Otherwise, there is gradual invasion by weedy shrubs and small trees.
T2A	-	State 2 Invaded Understory transitions to State 1 Reference by land clearing with heavy machinery followed by weed control. Land clearing can promote germination of the weed seed bank in the soil, requiring weed control. After clearing and weed control, the site would be planted to forage species.
R2A	-	State 2 Invaded Understory may be restored to a facsimile of State 3 Native Forest State, by removal of the introduced understory through weed control measures. Reintroduction of native understory species is required. The site must be fenced securely to exclude ungulates.
T2B	-	State 2 Invaded Understory transitions to State 5 Exotic Tree Invaded by growth of introduced tree species through and above the native canopy. Lack of reproduction leads to gradual loss of most native plants.
T3B	-	State 3 Native Forest transitions to State 1 Naturalized Grassland by clearing the forest and planting desirable forage species.
T3A	-	State 3 Native Forest State transitions to State 2 Invaded Understory through grazing, browsing, rooting, and trampling by domestic or feral ungulates (cows, sheep, deer, goats, and pigs). These activities destroy small native plant species and seedlings and saplings of large species. Regeneration of the native forest is prevented, leading to tree populations consisting almost entirely of mature plants. Lack of competition from native plants, introduction of weed seeds, and disturbance of the soil lead to an understory dominated by introduced plant species. Weeds can invade intact native forest even in the absence of ungulates and gradually bring about the transition. Invasive vines, shrubs, and small trees will grow under intact native canopies and begin to degrade the forest. Eventually, introduced grasses provide fine fuels that can carry intense fires that destroy the native tree canopy.
R4A	-	State 4 Exotic Tree Invaded State can be restored to State 1 Reference by brush management with follow-up control of re-sprouting shrubs and emerging weedy forbs. Forage species may be replanted and maintained by prescribed grazing.
T4A	-	State 4 Shrub Invaded Grassland transitions to State 5 Exotic Tree Invaded with lack of fire. Fast-growing introduced tree species invade Shrub Invaded Grassland and overtop shrubs, or christmasberry increases in stature and density to become dominant.
R5B	-	State 5 Exotic Tree Invaded State may be restored to State 1 Reference. Total clearing of the site would be necessary. If clearing is done by heavy machinery, soil disturbance would occur. This would probably induce germination of the weed seed bank and also increase the potential for soil erosion. Weed control and brush management must then be applied multiple times to control new weed germination and resprouting. After clearing and weed control, the site would be planted to forage species. Ungulates must be excluded until forages are well established; prescribed grazing must then be applied.
R5A	-	It may be possible to restore State 5 Exotic Tree Invaded to a community resembling State 3 Native Forest. Total clearing of the site would be necessary. Alternatively, it may be worthwhile to kill taller weed species in place in order to provide some shelter for the ground. If clearing is done by heavy machinery, soil disturbance would occur. This could induce germination of the weed seed bank and also increase the potential for soil erosion. Weed control would be ongoing. Protection from fire is needed, and ungulates must be excluded by a suitable fence.

State 1 submodel, plant communities

1.2. Kikuyugrass – molassesgrass

P1.1A	-	Community phase 1.1 converts to phase 1.2 by continuous grazing without adequate rest for preferred forages. This conversion can be avoided by timely application of deferred and/or prescribed grazing to allow recovery of desirable species after grazing or browsing.
P1.2A	-	Community phase 1.1 converts to phase 1.2 by continuous grazing without adequate rest for preferred forages. This conversion can be avoided by timely application of deferred and/or prescribed grazing to allow recovery of desirable species after grazing or browsing.

State 1
Reference State

This state consists of two community phases. It is naturalized grassland with introduced grasses, forbs, and trees. Scattered large trees are sometimes present.

Community 1.1
Koa haole (white leadtree)/kikuyugrass-guineagrass

This community phase consists of introduced grasslands dominated by kikuyugrass at the upper elevations of this ecological site and guineagrass at moderate elevations. Buffelgrass may occur at the lowest leeward extremes. Preferred forage species are kikuyugrass, guineagrass, and koa haole, a small leguminous tree. Other forage species are Natal redtop or rose Natal grass (Melinis repens) and hilograss (Paspalum conjugatum). With continuous heavy grazing, particularly by cattle, preferred forage grasses decrease, as will preferred small trees, vines, and shrubs. Less preferred grass, forb, and shrub species increase under such circumstances. With severe deterioration, shrubby species can increase to eventually dominate.

Dominant plant species

white leadtree (Leucaena leucocephala), tree
kikuyugrass (Pennisetum clandestinum), grass
guineagrass (Urochloa maxima), grass

Community 1.2
Kikuyugrass – molassesgrass

Kikuyugrass and guineagrass are still the most abundant grass species but are now less dominant. Primary increaser grass species that increase under heavy grazing include molassesgrass (Melinis minutiflora), feather fingergrass (Chloris virgata), wiregrass or Indian goosegrass (Eleusine indica), rat-tail grass (Sporobolus africanus syn. S. indicus var. capensis), crabgrass (Digitaria spp.), and Bermudagrass (Cynodon dactylon). Unpalatable increaser forbs include sensitive partridge pea (Chamaecrista nictitans), sensitive plant or shameplant (Mimosa pudica), rattlepod (Crotalaria mucronata), red pualele or lilac tasselflower (Emilia sonchifolia), and spiny amaranth (Amaranthus spinosus). Shrubby species include lantana (Lantana camara), apple of Sodom (Solanum linnaeaum), false mallow (Malvastrum coromandelianum), Sacramento bur (Triumfetta semitriloba), balloon plant (Asclepias physocarpa), christmasberry (Schinus terebinthifolius), hairy mallow (Abutilon grandifolia), and castor bean (Ricinus communis).

Dominant plant species

kikuyugrass (Pennisetum clandestinum), grass
guineagrass (Urochloa maxima), grass
molassesgrass (Melinis minutiflora), grass

Pathway P1.1A
Community 1.1 to 1.2

Community phase 1.1 converts to phase 1.2 by continuous grazing without adequate rest for preferred forages. This conversion can be avoided by timely application of deferred and/or prescribed grazing to allow recovery of desirable species after grazing or browsing.

Pathway P1.2A
Community 1.2 to 1.1

State 2
Invaded Understory State

This state consists of one community phase having an open or closed canopy of common native trees with an understory of introduced grasses, ferns, vines, small trees, and shrubs. Foraging by feral or domestic ungulates removes native understory plants and prevents regeneration of overstory species, resulting in a mature and diminishing canopy of native trees. This may occur more gradually by weed invasion into intact native forest. The understory of this plant community contains fine fuels, particularly grasses, that are susceptible to intense fires.

Dominant plant species

'ohi'a lehua (Metrosideros polymorpha), tree
Hawai'i olive (Nestegis sandwicensis), tree
pukiawe (Styphelia tameiameiae), shrub
lantana (Lantana camara), shrub
molassesgrass (Melinis minutiflora), grass

Community 2.1
Ohia lehua - olopua/pukiawe – lantana/molassesgrass

Native tree species dominate the overstory. The understory consists of a variable array of introduced plant species along with remnant native species. The overstory is dominated by ohia lehua, olopua, and other typical native dry forest species such as Hawaii kauilatree (Alphitonia ponderosa) and lama (Diospyros sandwicensis). Among native shrubs, aalii (Dodonaea viscosa) and pukiawe (Leptecophylla tameiameiae) may still be present. The introduced shrub lantana (Lantana camara) can be very abundant. The introduced vine huehue haole or corkystem passionflower (Passiflora suberosa) can become very abundant, covering the canopies of remnant, low-stature native understory plants. Introduced grass species are abundant beneath the overstory canopy, which generally is not adequately dense to inhibit their growth. Christmasberry or Brazilian pepper tree (Schinus terebinthifolius), an introduced small tree that produces a dense, shady canopy, may be abundant.

Dominant plant species

'ohi'a lehua (Metrosideros polymorpha), tree
Hawai'i olive (Nestegis sandwicensis), tree
pukiawe (Styphelia tameiameiae), shrub
lantana (Lantana camara), shrub
molassesgrass (Melinis minutiflora), grass

State 3
Native Forest State

This state consists of one community phase. This description is hypothetical, because very little native vegetation remains in this ecological site. The following description is based on similar ecological sites. The general appearance of this ecological site is an open to nearly closed canopy up to 40 feet (12 meters) tall, an understory of shrubs and small trees, and a ground layer of vines, forbs, and grasses. The canopy becomes shorter and sparser where the forest grades into drier areas near the coast.

Community 3.1
Ohia lehua – olopua/pukiawe

The tree canopy is dominated by ohia lehua (Metrosideros polymorpha) and typical dry forest species such as olopua (Nestegis sandwicensis), lama (Diospyros sandwicensis), and ae or Hawaii brushholly (Xylosma hawaiiense). Alahee (Psydrax odorata), a small tree or shrub, is common in the understory. Common shrubs are pukiawe (Leptocophylla (Styphelia) tameiameiae), aalii (Dodonaea viscosa), ilima (Sida fallax), ulei (Osteomeles anthyllidifolia), and hillside false ohelo (Wikstroemia uva-ursi). Huehue (Cocculus orbiculatus) is the most common vine. Native forbs, grasses, and ferns are present but not abundant.

Dominant plant species

'ohi'a lehua (Metrosideros polymorpha), tree
Hawai'i olive (Nestegis sandwicensis), tree
pukiawe (Styphelia tameiameiae), shrub

State 4
Shrub Invaded Grassland State

This state consists of one community phase. It may have developed from abandoned grazing land, land cleared by wildfire, or abandoned farmland. Shrubs are dominant in canopy cover and stature. Typically, an array of introduced grass species is present. There is a moderate but increasing cover of small trees, some which potentially can grow to large stature. This tree cover creates the potential for a transition to State 5 Exotic Tree Invaded.

Community 4.1
Christmasberry (Brazilian peppertree)/lantana/kikuyugrass – molassesgrass

This community is dominated by small trees, shrubs, and grasses. The most common introduced trees present are christmasberry (Schinus terebinthifolius) and, if it has not been eliminated by excessive browsing, koa haole (Leucaena leucocephala). Lantana (Lantana camara) is the most common shrub. Molassesgrass is common between shrubs and beneath koa haole.

Dominant plant species

Brazilian peppertree (Schinus terebinthifolius), shrub
lantana (Lantana camara), shrub
kikuyugrass (Pennisetum clandestinum), grass
molassesgrass (Melinis minutiflora), grass

State 5
Exotic Tree Invaded State

This state is comprised of one community phase dominated by introduced trees. Density and composition of understory shrubs, forbs, and grasses varies greatly with overstory closure and height, which affects the susceptibility of this plant community to fire. The density, vigor, and biomass of introduced vegetation can be very high, making restoration to other states expensive and difficult.

Community 5.1
Christmasberry (Brazilian peppertree) – common guava/lantana

In many cases, the overstory consists of very dense christmasberry that is 15 to 25 feet (4.5 to 3.25 meters) tall with very little understory. Introduced tree species such as silk oak (Grevillea robusta), autograph tree (Clusia rosea), kukui (Aleurites moluccana), and octopus tree (Schefflera actinophylla) that have greater height potentials than christmasberry may overtop the christmasberry canopy and eventually dominate the site. Remnant, mature ohia lehua (Metrosideros polymorpha) trees may be present but are not able to regenerate. Native alahee (Psydrax odorata) trees sometimes are able to reproduce and maintain a sparse population in the understory. The overstory composition can be highly variable from site to site, but christmasberry is often the most abundant species. Christmasberry often dominates the understory (<13 feet or 4 meters tall) and can be so dense as to exclude most other species. Where more light is available, the small, introduced trees common guava (Psidium guajava) and koa haole (Leucaena leucocephala) are common. Lantana (Lantana camara) is the most common shrub.

Dominant plant species

Brazilian peppertree (Schinus terebinthifolius), tree
guava (Psidium guajava), tree
lantana (Lantana camara), shrub

Restoration pathway R1A
State 1 to 3

It is possible to restore State 1 Reference to a plant community resembling State 3 Native Forest. Weed control must be applied to forage species and the many opportunistic plant species that would invade the site. Weed control would be a perpetual process to maintain the site. Fire must be excluded. Domestic and feral ungulates must be excluded by a suitably designed and maintained fence. Extensive planting of native species would follow.

Transition T1A
State 1 to 4

State 1 Reference transitions to State 4 Shrub Invaded Grassland through further overgrazing or abandonment. Fire will temporarily prevent this transition. Koa haole will be greatly reduced by over browsing. If the site contained abundant koa haole and was then abandoned, these small trees can greatly increase in abundance. Otherwise, there is gradual invasion by weedy shrubs and small trees.

Transition T2A
State 2 to 1

State 2 Invaded Understory transitions to State 1 Reference by land clearing with heavy machinery followed by weed control. Land clearing can promote germination of the weed seed bank in the soil, requiring weed control. After clearing and weed control, the site would be planted to forage species.

Restoration pathway R2A
State 2 to 3

State 2 Invaded Understory may be restored to a facsimile of State 3 Native Forest State, by removal of the introduced understory through weed control measures. Reintroduction of native understory species is required. The site must be fenced securely to exclude ungulates.

Transition T2B
State 2 to 5

State 2 Invaded Understory transitions to State 5 Exotic Tree Invaded by growth of introduced tree species through and above the native canopy. Lack of reproduction leads to gradual loss of most native plants.

Transition T3B
State 3 to 1

State 3 Native Forest transitions to State 1 Naturalized Grassland by clearing the forest and planting desirable forage species.

Transition T3A
State 3 to 2

State 3 Native Forest State transitions to State 2 Invaded Understory through grazing, browsing, rooting, and trampling by domestic or feral ungulates (cows, sheep, deer, goats, and pigs). These activities destroy small native plant species and seedlings and saplings of large species. Regeneration of the native forest is prevented, leading to tree populations consisting almost entirely of mature plants. Lack of competition from native plants, introduction of weed seeds, and disturbance of the soil lead to an understory dominated by introduced plant species. Weeds can invade intact native forest even in the absence of ungulates and gradually bring about the transition. Invasive vines, shrubs, and small trees will grow under intact native canopies and begin to degrade the forest. Eventually, introduced grasses provide fine fuels that can carry intense fires that destroy the native tree canopy.

Restoration pathway R4A
State 4 to 1

State 4 Exotic Tree Invaded State can be restored to State 1 Reference by brush management with follow-up control of re-sprouting shrubs and emerging weedy forbs. Forage species may be replanted and maintained by prescribed grazing.

Transition T4A
State 4 to 5

State 4 Shrub Invaded Grassland transitions to State 5 Exotic Tree Invaded with lack of fire. Fast-growing introduced tree species invade Shrub Invaded Grassland and overtop shrubs, or christmasberry increases in stature and density to become dominant.

Restoration pathway R5B
State 5 to 1

State 5 Exotic Tree Invaded State may be restored to State 1 Reference. Total clearing of the site would be necessary. If clearing is done by heavy machinery, soil disturbance would occur. This would probably induce germination of the weed seed bank and also increase the potential for soil erosion. Weed control and brush management must then be applied multiple times to control new weed germination and resprouting. After clearing and weed control, the site would be planted to forage species. Ungulates must be excluded until forages are well established; prescribed grazing must then be applied.

Restoration pathway R5A
State 5 to 3

It may be possible to restore State 5 Exotic Tree Invaded to a community resembling State 3 Native Forest. Total clearing of the site would be necessary. Alternatively, it may be worthwhile to kill taller weed species in place in order to provide some shelter for the ground. If clearing is done by heavy machinery, soil disturbance would occur. This could induce germination of the weed seed bank and also increase the potential for soil erosion. Weed control would be ongoing. Protection from fire is needed, and ungulates must be excluded by a suitable fence.

Additional community tables

Supporting information

Other references

ANNOTATED REFERENCES

Abrahamson I. 2013. Fire regimes in Hawaiian plant communities. In: Fire Effects Information System, US Dept. of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory. Available" www.fs.fed.us/database/feis/fire_regimes/Hawaii/all.html Review of fire regimes and history for multiple generalized plant communities in the Hawaiian Islands.

Armstrong RW. 1973. Atlas of Hawaii. University of Hawaii Press, Honolulu. General reference for climate, land use, land forms, etc.

Athens JS. Ch. 12 Hawaiian Native Lowland Vegetation, IN Prehistory in Historical Ecology in the Pacific Islands – Prehistoric Environmental and Landscape Change. Kirch, PV and TL Hunt, eds. 1997. Yale U. Press, New Haven. General discussion of effects of prehistoric Polynesians on native lowland vegetation.

Burney DA, HF James, LP Burney, SL Olson, W Kikuchi, WL Wagner, M Burney, D McCloskey, D Kikuchi, FV Grady, R Gage II, and R Nishek. 2001. Fossil evidence for a diverse biota from Kauai and its transformation since human arrival. Ecological Monographs 71:615-641. General discussion of effects of prehistoric Polynesians on native vegetation.

Christensen CC. 1983. Report 17: Analysis of land snails. In Archaeological investigations of the Mudlane-Waimea-Kawaihae Road Corridor, Island of Hawaii: an Interdisciplinary Study of an Environmental Transect. Clark JT. and Kirch PV, eds. Dept. of Anthropology, Bernice Pauahi Bishop Museum, Report 83-1, Honolulu, HI. Native land snails as indicators of original vegetation and environment along a climatic transect. Specific to Kohala, Island of Hawaii, but information can be generally applied to other islands.

Clark JT. 1983. Report 3: The Waimea-Kawaihae Region: Historical Background. In Archaeological investigations of the Mudlane-Waimea-Kawaihae Road Corridor, Island of Hawaii: an Interdisciplinary Study of an Environmental Transect. Clark JT and Kirch PV, eds. Dept. of Anthropology, Bernice Pauahi Bishop Museum, Report 83-1, Honolulu, HI. Historical landuse along a climatic transect. Specific to Kohala, Island of Hawaii, but information can be generally applied to other islands.

Clark JT. 1983. Report 7: Archaeological investigations in Section 4. In Archaeological investigations of the Mudlane-Waimea-Kawaihae Road Corridor, Island of Hawaii: an Interdisciplinary Study of an Environmental Transect. Clark JT and Kirch PV, eds. Dept. of Anthropology, Bernice Pauahi Bishop Museum, Report 83-1, Honolulu, HI. Prehistoric landuse along a climatic transect. Specific to Kohala, Island of Hawaii, but information can be generally applied to other islands.

Clark JT. 1983. Report 8: Archaeological investigations of agricultural sites in the Waimea area. In Archaeological investigations of the Mudlane-Waimea-Kawaihae Road Corridor, Island of Hawaii: an Interdisciplinary Study of an Environmental Transect. Clark JT and Kirch PV, eds. Dept. of Anthropology, Bernice Pauahi Bishop Museum, Report 83-1, Honolulu, HI. Prehistoric landuse along a climatic transect. Specific to Kohala, Island of Hawaii, but information can be generally applied to other islands.

Craighill ES and EG Handy. 1991. Native Planters in Old Hawaii – Their Life, Lore, and Environment. Bernice P. Bishop Museum Bulletin 233, Bishop Museum Press, Honolulu, HI Discussion of early agriculture in Hawaii.

Cuddihy LW and CP Stone. 1990. Alteration of Native Hawaiian Vegetation: Effects of Humans, Their Activities and Introductions. Honolulu: University of Hawaii Cooperative National Park Resources Study Unit. General account of human effects on native Hawaiian vegetation.

Deenik J and AT McClellan. 2007. Soils of Hawaii. Soil and Crop Management, Sept. 2007, SCM-20. Cooperative Extension Service, College of Tropical Agriculture and Human Resources. University of Hawaii at Manoa. Available online at: https://www.ctahr.hawaii.edu/oc/freepubs/pdf/SCM-20.pdf Discussion of soil orders and their practical implications in Hawaii.

Dixon JB and Schulze DG, eds. 2002. Soil Mineralogy with Environmental Applications. Volume 7. Soil Science Society of America. Available online at: https://acsess.onlinelibrary.wiley.com/doi/book/10.2136/sssabookser7 Exhaustive treatment of basics of soil mineralogy and implications for environmental management.

Giambelluca TW and TA Schroeder. 1998. Climate. In Atlas of Hawaii, 3rd edition. SP Juvik, JO Juvik, and RR Paradise, eds. pp. 49-59. Honolulu: University of Hawaii Press. Standard geographical reference work for Hawaii.

Hazlett RW and DW Hyndman. 1996. Roadside Geology of Hawaii. Mountain Press Publishing Company, Missoula MT. General account of geologic history of Hawaii.

Henke LA. 1929. A Survey of Livestock in Hawaii. Research Publication No. 5. University of Hawaii, Honolulu. Provides early accounts of introduction and spread of ungulates in Hawaii.

Horrocks M. 2009. Sweet potato (Ipomoea batatas) and banana (Musa sp.) microfossils in deposits from the Kona Field System, Island of Hawaii. Journal of Archaeological Science, May 2009. Specific to Kona on the Island of Hawaii, but useful information about early Hawaiian land use and agriculture.

Imada, C. 2012. Hawaiian Native and Naturalized Vascular Plants Checklist (December 2012 update). Bishop Museum Technical Report 60. Bishop Museum Press, Honolulu. Constantly-updated list of vascular plants of Hawaii, including latest nomenclature and species occurrences on each island.

Kirch PV. 1982. The impact of the prehistoric Polynesians in the Hawaiian ecosystem. Pacific Science 36(1):1-14. General discussion of effects of prehistoric Polynesians on native vegetation.

Kirch PV. 1983. Introduction. In Archaeological investigations of the Mudlane-Waimea-Kawaihae Road Corridor, Island of Hawaii: An Interdisciplinary Study of an Environmental Transect. Clark JT and Kirch PV, eds. Dept. of Anthropology, Bernice Pauahi Bishop Museum, Report 83-1, Honolulu, HI. Generalized account of land use and vegetation along a climatic transect. Specific to Kohala on the Island of Hawaii, but generally applicable to other islands.

Kirch PV. 1985. Feathered Gods and Fishhooks: An Introduction to Hawaiian Archaeology and Prehistory. Honolulu: University of Hawaii Press. General discussion of effects of prehistoric Polynesians on native vegetation.

Kirch PV. 2000. On the Road of the Winds: An Archaeological History of the Pacific Islands Before European Contact. Berkeley: University of California Press. General discussion of effects of prehistoric Polynesians on native vegetation.

Little EL Jr. and RG Skolmen. 1989. Common Forest Trees of Hawaii (Native and Introduced). US Department of Agriculture-US Forest Service Agriculture Handbook No. 679. (out of print). Available at www.fs.fed.us/psw/publications/documents/misc/ah679.pdf Information on common native and introduced tree species in Hawaii. Especially useful for introduced species.

Maly K and O Maly. 2004. He Moolelo Aina: A Cultural Study of the Puu O Umi Natural Area Reserve and Kohala-Hamakua Mountain Lands, Districts of Kohala and Hamakua, Island of Hawaii. Kumu Pono Associates, Hilo HI. Account of natural vegetation and human effects that can be applied to all related ecological sites.

McEldowney H. 1983. Report 16: A description of major vegetation patterns in the Waimea-Kawaihae region during the early historic period. Archaeological investigations of the Mudlane-Waimea-Kawaihae Road Corridor, Island of Hawaii: An Interdisciplinary Study of an Environmental Transect. Clark JT and Kirch PV, eds. Dept. of Anthropology, Bernice Pauahi Bishop Museum, Report 83-1, Honolulu, HI. Generalized account of land use and vegetation along a climatic transect. Specific to Kohala on the Island of Hawaii, but generally applicable to other islands.

Mueller-Dombois D and FR Fosberg. 1998. Vegetation of the Tropical Pacific Islands. Springer-Verlag New York, Inc. General account of tropical Pacific Island vegetation, with section on Hawaii. Discussion of likely effect of stoniness on soil moistue storage in dry habitats.

Palmer DD. 2003. Hawaii’s Ferns and Fern Allies. University of Hawaii Press, Honolulu. Standard reference for Hawaiian ferns and fern allies.

Pratt HD. 1998. A Pocket Guide to Hawaii’s Trees and Shrubs. Mutual Publishing, Honolulu. Useful guide to common tree and plant species, with color photos.

Reppun F, Silva JHS, Wong K, and Deenik JL. 2017. A Soil Phosphorus Primer for Hawaiian Soils. Soil and Crop Management, August 2017, SCM-33. College of Tropical Agriculture and Human Resources, University of Hawaii at Manoa. Available online at: https://www.ctahr.hawaii.edu/oc/freepubs/pdf/SCM-33.pdf Practical discussion of soil phosphorus for Hawaii.

Ripperton JC and EY Hosaka. 1942. Vegetation zones of Hawaii. Hawaii Agricultural Experiment Station Bulletin 89:1-60. Broad-scale map of vegetation zones in Hawaii.

Rock JF. The Indigenous Trees of the Hawaiian Islands. 1st edition 1913, reprinted 1974, Charles E. Tuttle Company, Rutland, VT and Tokyo, Japan. Very useful account observations of native vegetation in Hawaii from early 20th century. Can be paired with GIS layer of place names to locate species observations.

Shoji SD, M Nanzyo, and R Dahlgren. 1993. Volcanic Ash Soils: Genesis, Properties and Utilization. Elsevier, New York. Detailed discussion of volcanic ash soils. Not specific to Hawaii, but very informative.

Silva JA and R Uchida, eds. 2000. Plant Nutrient Management in Hawaii’s Soils, Approaches for Tropical and Subtropical Agriculture. College of Tropical Agriculture and Human Resources, University of Hawaii at Manoa. Available online at: https://www.ctahr.hawaii.edu/oc/freepubs/pdf/pnm0.pdf Practical discussion of plant nutrient management for Hawaii.

Sohmer SH and R Gustafson. 2000. Plants and Flowers of Hawaii. University of Hawaii Press, Honolulu. A good general discussion, with color photographs, primarily of native Hawaiian plants and vegetation types.

Soil Survey Staff. 2014. Soil Taxonomy, Twelfth Edition. USDA – NRCS. Standard book of soil taxonomy; useful for terminology and interpretation of soils, also.

Steadman DW. 1995. Prehistoric extinctions of Pacific island birds: biodiversity meets zooarchaeology. Science 267:1123-1131. Discussion of loss of many bird species, including flightless birds, with information about disturbances and vegetation changes.

USDA-NRCS-PIA Threatened & Endangered Species GIS files. Not publicly available. Specific locations of observations of many native Hawaiian plant species.

USDA-NRCS. 2011. Soil Survey Laboratory Information Manual. Soil Survey Investigations Report No. 45, Version 2.0. National Soil Survey Center, Lincoln, Nebraska. Detailed information about interpretation of soil laboratory results.

USDA-NRCS. 2006. Major Land Resource Regions. USDA Agriculture Handbook 296. http://soils.usda.gov/MLRAExplorer Description of MLRAs of Hawaii.

USDA-NRCS. Island of Hawaii Soil Surveys 801 and 701. Available online at https://websoilsurvey.sc.egov.usda.gov/App/HomePage.htm The latest NRCS soil survey for the island of Hawaii.

USDA-SCS. 1972. Soil Survey of Islands of Kauai, Oahu, Maui, Molokai, and Lanai, State of Hawaii. Foote DE, Hill EL, Nakamura S, and F Stephens, in cooperation with The University of Hawaii Agricultural Experiment Station. The latest NRCS soil survey for these islands. Some of the taxonomic names are outdated.

USDI-USGS. 2006. A GAP Analysis of Hawaii. Final Report and Data. GIS map of vegetation types and land use in Hawaii based on remote sensing. Very general, occasionally inaccurate, but useful.

Vitousek P. 2004. Nutrient Cycling and Limitation: Hawai`i as a Model Ecosystem. Princeton University Press, Princeton and Oxford. Discussion of development of soils, soil nutrients, and plant species in Hawaiian Archipelago.

Wagner WL, DR Herbst, and SH Sohmer. 1999. Manual of the Flowering Plants of Hawaii, Revised Edition. Bishop Museum Press, Honolulu. Standard reference of flowering plants of Hawaii.

Welch DJ 1983. Report 5: Archaeological investigations in Section 2. In Archaeological investigations of the Mudlane-Waimea-Kawaihae Road Corridor, Island of Hawaii: An Interdisciplinary Study of an Environmental Transect. Clark JT and Kirch PV, eds. Dept. of Anthropology, Bernice Pauahi Bishop Museum, Report 83-1, Honolulu, HI. Prehistoric landuse along a climatic transect. Specific to Kohala, Island of Hawaii, but information can be generally applied to other islands.

Western Regional Climate Center, cited 2020. Climate of Hawaii. Available: https://wrcc.dri.edu/Climate/narrative_hi.php Detailed summary of climate of Hawaiian Islands.

Whistler, WA. 1995. Wayside Plants of the Islands: A Guide to the Lowland Flora of the Pacific Islands. Isle Botanica, Honolulu. Reference of common introduced plant species in lowland areas of the Pacific Islands including Hawaii; with color photographs.

DEFINITIONS

Aa lava: A type of basaltic lava having a rough, jagged, clinkery surface and a vesicular interior.

Ash field: a land area covered by a thick or distinctive deposit of volcanic ash that can be traced to a specific source and has well defined boundaries. The term “ash flow” is erroneously used in the Physiographic section of this ESD due to a flaw in the national database.

Ashy: A “soil texture modifier” for volcanic ash soils having a water content at the crop wilting point of less than 30 percent; a soil that holds relatively less water than “medial” and “hydrous” soils.

Available water capacity: The amount of soil water available to plants to the depth of the first root-restricting layer.

CaCO3 equivalent: The amount of free lime in a soil. Free lime exists as solid material and typically occurs in regions with a dry climate.

Canopy cover: The percentage of ground covered by the vertical projection downward of the outermost perimeter of the spread of plant foliage. Small openings within the canopy are included.

Community pathway: A description of the causes of shifts between community phases. A community pathway is reversible and is attributable to succession, natural disturbances, short-term climatic variation, and facilitating practices, such as grazing management.

Community phase: A unique assemblage of plants and associated dynamic soil properties within a state.

Dominant species: Plant species or species groups that exert considerable influence upon a community due to size, abundance, or cover.

Drainage class: The frequency, duration, and depth of a water table in a soil. There are seven drainage classes, ranging from “excessively drained” (soils with very rare or very deep water tables) to “well drained” (soils that provide ample water for plant growth but are not so wet as to inhibit root growth) to “very poorly drained” (soils with a water table at or near the surface during much of the growing season that inhibits growth of most plants).

Electrical conductivity (EC): A measure of the salinity of a soil. The standard unit is deciSiemens per meter (dS/m), which is numerically equivalent to millimhos per centimeter (mmhos/cm). An EC greater than about 4 dS/m indicates a salinity level that is unfavorable to growth of most plants.

Friability: A soil consistency term pertaining to the ease of crumbling of soils.

Ion exchange capacity: The ability of soil materials such as clay or organic matter to retain ions (which may be plant nutrients) and to release those ions for uptake by roots.

Isothermic soil temperature regime: A regime in which mean annual soil temperature is 59 degrees F (15 degrees C) or higher but lower than 72 degrees F (22 degrees C) and mean summer and mean winter soil temperatures differ by less than 11 degrees F (6 degrees C) at a specified depth.

Major Land Resource Area (MLRA): A geographic area defined by NRCS that is characterized by a particular pattern of soils, climate, water resources, and land uses. The island of Hawaii contains nine MLRAs, some of which also occur on other islands in the state.

Makai: a Hawaiian word meaning “toward the sea.”

Mauka: a Hawaiian word meaning “toward the mountain” or “inland.”

Medial: A “soil texture modifier” for volcanic ash soils having a water content at the crop wilting point of 30 to 100 percent; a soil that holds an amount of water intermediate to “hydrous” or “ashy” soils.

Naturalized plant community: A community dominated by adapted, introduced species. It is a relatively stable community resulting from secondary succession after disturbance. Most grasslands in Hawaii are in this category.

Oxisols: Soils characteristic of humid, tropical or subtropical regions that formed on land surfaces that have been stable for a long time. In Hawaii, they typically occur on islands or parts of islands that have been volcanically inactive for a long time. Oxisols are highly weathered, consist largely of quartz, kaolin clays, and aluminum oxides, and have low ion exchange capacity and loamy or clayey texture.

Pahoehoe lava: A type of basaltic lava with a smooth, billowy, or rope-like surface and vesicular interior.

Parent material: Unconsolidated and chemically weathered material from which a soil is developed.

pH: The numerical expression of the relative acidity or alkalinity of a soil sample. A pH of 7 is neutral; a pH below 7 is acidic and a pH above 7 is basic.

Phosphorus adsorption: The ability of soil materials to tightly retain phosphorous ions, which are a plant nutrient. Some volcanic ash soils retain phosphorus so strongly that it is partly unavailable to plants.

Reference community phase: The phase exhibiting the characteristics of the reference state and containing the full complement of plant species that historically occupied the site. It is the community phase used to classify an ecological site.

Reference state: A state that describes the ecological potential and natural or historical range of variability of an ecological site.

Residuum: Unconsolidated mineral material that has chemically and physically weathered from rock and has not moved from its place of origin.

Restoration pathway: A term describing the environmental conditions and practices that are required to recover a state that has undergone a transition.

Sodium adsorption ratio (SAR): A measure of the amount of dissolved sodium relative to calcium and magnesium in the soil water. SAR values higher than 13 create soil conditions unfavorable to most plants.

Soil moisture regime: A term referring to the presence or absence either of ground water or of water held at a tension of less than 1500 kPa (the crop wilting point) in the soil or in specific horizons during periods of the year.

Soil temperature regime: A defined class based on mean annual soil temperature and on differences between summer and winter temperatures at a specified depth.

Soil reaction: Numerical expression in pH units of the relative acidity or alkalinity or a soil.

Spodosols: Soils with a spodic B horizon that has an accumulation of black or reddish amorphous materials that have a high pH-dependent ion exchange capacity, coarse texture, and few base cations. Above the spodic horizon there often is a light-colored albic horizon that was the source of the amorphous materials in the spodic horizon.

State: One or more community phases and their soil properties that interact with the abiotic and biotic environment to produce persistent functional and structural attributes associated with a characteristic range of variability.

State-and-transition model: A method used to display information about relationships between vegetation, soil, animals, hydrology, disturbances, and management actions on an ecological site.

Transition: A term describing the biotic or abiotic variables or events that contribute to loss of state resilience and result in shifts between states.

Ultisols: Soils that have been intensively leached and weathered. They have a B horizon that has accumulated clay that has translocated there from higher horizons. They have moderate to low cation exchange capacity and low base saturation. The highest base saturation normally is in the few centimeters directly beneath the surface due to cycling of bases by plants.

Ustic soil moisture regime: A regime in which moisture is limited but present at a time when conditions are suitable for plant growth. In Hawaii it usually is associated with dry forests and subalpine shrublands.

Contributors

David Clausnitzer
John Proctor
Mike Kolman
Carolyn Auweloa
Jennifer Higashino
Kendra Moseley
Mathew Cocking
Amy Koch

Approval

Kendra Moseley, 5/08/2025

Acknowledgments

Assistance, advice, review, and/or insights:

Randy Bartlett, Puu Kukui Watershed Preserve
Alison Cohan, The Nature Conservancy
Michael Constantinides, NRCS-PIA
Gordon Cran, Kapapala Ranch
Diana Crow, Ulupalakua Ranch
Lance DeSilva, Hawaii DLNR
Kerri Fay, Waikamoi Preserve, The Nature Conservancy
Alex Franco, Kaupo Ranch
Ranae Ganske-Cerizo, NRCS
Carl Hashimoto, NRCS
Bob Hobdy, consultant, Maui
Wallace Jennings, NRCS
Mel Johansen, The Nature Conservancy
Jordan Jokiel, Haleakala Ranch
David Leonard, volunteer
Penny Levin
Reese Libby, GIS - NRCS
Hannah Lutgen, Maui SWCD
Joseph May, NRCS
Scott Meidel, Haleakala Ranch
Anna Palomino, Hoolawa Farms Inc.
Jon Price, USGS
Tamara Sherrill, USFWS, Maui Nui Botanical Garden
Amber Starr, Hana Ranch
Kahana Stone, NRCS
Mark Vaught, Water Resources, Alexander & Baldwin
Jacqueline Vega, NRCS
Rich von Wellsheim, Whispering Bamboos, Kipahulu

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	05/09/2025
Approved by	Kendra Moseley
Approval date
Composition (Indicators 10 and 12) based on	Annual Production

Indicators

Number and extent of rills:
Presence of water flow patterns:
Number and height of erosional pedestals or terracettes:
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
Number of gullies and erosion associated with gullies:
Extent of wind scoured, blowouts and/or depositional areas:
Amount of litter movement (describe size and distance expected to travel):
Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
Presence and thickness of compaction layer (usually none; describe soil profile features which may be mistaken for compaction on this site):
Functional/Structural Groups (list in order of descending dominance by above-ground annual-production or live foliar cover using symbols: >>, >, = to indicate much greater than, greater than, and equal to):

Dominant:

Sub-dominant:

Other:

Additional:
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
Average percent litter cover (%) and depth ( in):
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
Potential invasive (including noxious) species (native and non-native). List species which BOTH characterize degraded states and have the potential to become a dominant or co-dominant species on the ecological site if their future establishment and growth is not actively controlled by management interventions. Species that become dominant for only one to several years (e.g., short-term response to drought or wildfire) are not invasive plants. Note that unlike other indicators, we are describing what is NOT expected in the reference state for the ecological site:
Perennial plant reproductive capability:

Download reference sheet

Click on box and path labels to scroll to the respective text.

Ecosystem states

4. Shrub Invaded Grassland State

3. Native Forest State

States 1, 5 and 2 (additional transitions)