Physiographic features

This ecological site occurs on volcanic ash deposited over lava flows on mountain slopes, interfluves and coastal plains of shield volcanoes. Lava flows are mostly aa (loose, cobbly), although there are smaller areas of pahoehoe and alluvium.

Table 2. Representative physiographic features

Climatic features

(Unless otherwise cited, the information in this section is derived from Western Regional Climate Center, cited 2020).

General principles
Air temperature in the Hawaiian Islands is buffered by the surrounding ocean so that the range in temperature through the year is narrow. This creates “iso-“ soil temperature regimes in which mean summer and winter temperatures differ by less than 6 degrees C (11 degrees F).

The islands lie within the trade wind zone. Significant amounts of moisture are picked up from the ocean by trade winds up to an altitude of more than about 6000 feet (1850 meters). As the trade winds from the northeast are forced up the mountains of the islands their moisture condenses, creating rain on the windward slopes; the leeward sides of the island receive less of this moisture, depending on the height of the mountains.

Hawaiian indigenous understanding recognized two seasons: Kau or Kauwela (dry season) when the sun was directly overhead, days are long and warm and tradewinds are stronger and more consistent; Kau started on the first new moon in May when the Pleiades set at sunrise (Handy, 1991). During Ho’oilo (wet season) the sun is declined toward the south, days are shorter, temperatures cooler and winds more variable and generally started with the first new moon in November. Ho’oilo is also the season when extensive low-pressure systems often approach the islands from the west, producing heavy rainstorms that primarily affect the leeward sides, but can envelope the entire island. (Malo, 1903, Handy 1991, Sanderson, 1993). These seasons are mostly consistent with modern observations today. These phenomena of pressure systems and seasonal differences interact with the islands’ topography which together creates the various climate zones and patterns observed in the islands. One such general pattern can be seen in the differences in rainfall amounts between winter and summer; in low elevation dry areas the differences are greater whereas wetter areas exhibit less seasonal variation in rainfall.

Summary for this ecological site
Average annual precipitation in this ecological site ranges from 7 to 20 inches (175 to 500 millimeters). Most of the precipitation occurs from October through April. Average annual temperatures range from 73 to 76 degrees F (23 to 24 degrees C). Conditions typically are very dry. Rainfall occurs as occasional light trade wind showers that drift over from the windward side of the islands and as heavier rainfall during major winter storms. Major storms are important for soil moisture recharge, and the number of major storms is highly variable; drought can result from a winter with few or no storms. Due to the latitude, daylength varies little during the year, resulting in only about a 50 percent variation in solar energy input between June maximum to December minimum; this variation is somewhat less than that found in the continental United States. Conditions are generally clear; frequent cloudiness higher on the mountain slopes usually does not shade this area due to the angle of the sun.

Soils in the Mahukona series (map units 411 and 412) receive higher average annual rainfall (20 to 35 inches or 125 to 700 millimeters) than other soils in this ecological site due to their location at the extreme north tip of Kohala, where the prevailing winds bring more moisture around the peninsula.

Table 3. Representative climatic features

Climate stations used

• (1) MAKENA GOLF CRS 249.1 [USC00515842], Kihei, HI

• (2) PUUKOHOLA HEIAU 98.1 [USC00518422], Kamuela, HI

Influencing water features

Mostly ephemeral streams flow through small gulches during periods of heavy rainfall. These gulches are associated with the areas of alluvial soils occurring in this ecological site. The narrow zones through which water typically flows are often associated with higher kiawe density than surrounding areas. Broader alluvial zones sometimes have higher kiawe density throughout, but typically in these broader zones the higher kiawe density occurs only in the narrow areas in streambeds and down at the shoreline.

Soil features

Most of the soils in this ecological site formed from volcanic ash deposited over and in the interstices of basaltic aa lava. Soils in the Kawaihae series formed from volcanic ash deposited over pahoehoe. Although pahoehoe is thought of as having a solid surface, many pahoehoe flows cracked and/or were lifted from beneath, creating rock fragments like those found in aa. The lava rock fragments found in these soils range in size from gravel (up to 3 inches, or 2 mm to 76 mm) to stones (10 to 25 inches, or 250 mm to 600 mm), but are primarily cobbles (76 mm to 250 mm, or 3 to 10 inches) and gravel. Below the layer of rock fragments is massive lava called “bluerock.” Interstices between stones are filled with fine soil material near the surface. The deepest horizon typically consists of rocks with empty voids between them.

Soils in the Puako and Lalamilo series formed in alluvial volcanic ash deposited by ephemeral or permanent streams in small gulches; these soils make up a small part of the ecological site.

Soil temperature regimes are isohypothermic (very warm). Soil moisture regimes are torric (in normal years, dry for more than half of the growing season and moist for less than 90 consecutive days during the growing season) or, in Keawakapu and Mahukona soils, moister than torric, being intergrades between ustic and aridic (aridic is similar to torric). Basically, all the soils are similar as to soil moisture regime. All but the two alluvial soils are either stony, very stony, extremely stony, very cobbly, or extremely cobbly. This reduces the amount of soil material per unit of volume, which reduces overall water holding capacity of the soil. However, given the moderate to very rapid permeability of all the soils, it enables water to percolate to deeper horizons, which have finer textures and good water holding capacity in all the soils in this ecological site. This provides deep water storage for plants with tap roots, of which kiawe is the commonest example. Kiawe as a phreatophyte, thrives where it can access groundwater or deep soil moisture. Its taproot often reaches a depth of 20-25 m (Gallagher, 2010). Kiawe is also implicated as a potential cause of changes in local hydrology and mineral cycling due to it’s efficient water harvesting capability and nitrogen fixation (Dudley, 2014). All the soils are well drained. Surface soil pH of most of the soils ranges from 5.8 to 7.4; extreme pH in subsurface soils within 30 inches (75 centimeters) of the surface range from 6.8 to 8.6.

The volcanic ash soils of the Hawaiian Islands are derived mostly from basaltic ash that varies relatively little in chemical composition (Hazlett and Hyndman 1996; Vitousek 2004)). Most of these volcanic ash soils are classified today as Andisols, which have these general management characteristics: ion exchange capacity that varies with pH, but mostly retaining anions such as nitrate; high phosphorus adsorption, which restricts phosphorus availability to plants; excellent physical properties (low bulk density, good friability, weak stickiness, stable soil aggregates) for cultivation, seedling emergence, and plant root growth; resistance to compaction and an ability to recover from compaction following repeated cycles of wetting and drying; and high capacity to hold water, relative to apparent texture, that is available to plants. These characteristics are due to the properties of the parent material, the clay-size noncrystalline materials formed by weathering, and the soil organic matter accumulated during soil formation (Shoji et al. 1993).

MAKENA, OANAPUKA, WAIKUI, HAPUNA, LALAMILO, and PUAKO soils are classified as Torrands, or Andisols with a torric soil moisture regime. They are deep or very deep (40 to more than 60 inches or 100 to more than 150 centimeters) soils. They originally formed in volcanic ash and are old and weathered enough to exhibit characteristics of Andisols but not to have developed further into other soil orders.

Makena soils are stony and have no root-restricting layers.

Oanapuka soils are distinguished in this group by having vitric properties. This means they contain a large percentage of volcanic glass or coarser cinders and pumice that has not yet been weathered out of the soil. These soils have lower water holding capacity than other Andisols. However, they have other properties that are favorable to plant growth: They have lower phosphorus retention than other Andisols, so this nutrient is more available to plants; the basaltic glass weathers, releasing fresh plant nutrients; they have low bulk density, which is favorable to root penetration; and, although the mineral particles in these soils have variable charge, they develop cation exchange at pH around and above 6 (Oanapuka pH is 6.0 in the top 2 inches (5 centimeters), then ranges from 6.5 to 7.4 in the deep (to about 43 inches or 107 centimeters) layer that contains common to many roots. All other things being equal, Oanapuka soils are likely to have higher vegetation production than other soils in this ecological site.

Waikui and Hapuna soils are distinguished in this group by having mollic properties in their surface horizons. Please see the description of Keawakapu soils below for an explanation of mollic properties. These soils are all extremely cobbly. Hapuna soils are strongly cemented by calcium carbonate and silica in the horizon from about 12 to 17 inches (30 to 42 centimeters) deep; this horizon partly impedes root penetration below this depth.

Lalamilo and Puako soils formed in volcanic ash that was transported by water to form narrow alluvial deposits in gulches. They both have fine sandy loam texture with relatively low water holding capacity, but both receive intermittent runoff. Puako soils have a surface horizon with mollic properties (see discussion under Keawakapu soils below), and they are occasionally flooded for brief periods. Lalamilo soils are very strongly cemented by calcium carbonate and silica at depths of about 63 to 65 inches (160 to 165 centimeters), which is too deep to materially affect plant growth in this environment.

Soils of the KEAWAKAPU series are classified as Aridic Haplustolls. They originally formed in volcanic ash deposited in aa but are old and weathered enough to have developed beyond Andisols to the Mollisols soil order. They are shallow (10 to 20 inches, or 25 to 50 centimeters) soils but can be as deep as 30 inches (75 centimeters) in some locations. They have an ustic soil moisture regime but are even drier, intergrading to an aridic soil moisture regime. Many of the soils in very warm, dry parts of the Hawaiian Islands are Mollisols or have mollic properties. Some of their unique properties are a combination of a relatively thick, dark surface horizon (mollic epipedon) that does not become hard when dry, a dominance of calcium among the extractable cations, high (greater than 50 percent) base saturation, and a dominance of crystalline clay minerals of moderate or high cation-exchange capacity. Although Mollisols usually form under grass in seasonally dry climates, they can form under a forest ecosystem.

KAWAIHAE soils are classified as Aridisols, which have an aridic soil moisture regime, which is a regime in which defined parts of the soil are, in normal years, dry for more than half of the growing season and moist for less than 90 consecutive days during the growing season. Soils in this series are very cobbly, and there are high sodium contents occurring from about 16 inches (41 centimeters) depth to the pahoehoe lava at about 33 inches (84 centimeters). These sodic horizons are associated with prismatic structure, and the sodium contents may impede root density below about 24 inches (61 centimeters).

Adjoining the soils described above are areas mapped as MISCELLANEOUS AREAS. By definition, they have little or no soil and support little or no vegetation. In the Five Islands Soil Survey in which this ecological site is partly located, Miscellaneous Areas are extensive, and most were mapped by low-intensity reconnaissance methods that provide less-detailed information than that presented for soil series and their phases. In many cases, however, Miscellaneous Areas in Maui, Molokai, Lanai, Oahu, and Kauai are moderately- to well-vegetated and/or contain plant and animal species of interest to conservationists. They are either difficult to access or were not considered important enough at the time of this survey to warrant full expenditure of resources. They are described in the following paragraphs.

CINDER LAND (rCL) occurs in parent materials of a mix of cinders, pumice, and volcanic ash on cinder cones. it supports a scattering of plants but is sparsely vegetated compared to surrounding soils in this ecological site.

LAVA FLOWS, AA (rLW) are lava flows that are too young to have accumulated much soil (either organic or mineral) in the interstices between aa rocks. They support lichens and a few grasses, herbs, shrubs, and scrubby trees. The amount of vegetation they support is variable, but they are sparsely vegetated compared to surrounding soils in this ecological site.

VERY STONY LAND (rVS) on Maui occurs mostly in parent materials of aa lava with volcanic ash. Fifty to ninety percent of the surface is covered with stones and boulders. Some occurrences of Very Stony Land adjoining this ecological site support vegetation as dense as, or denser than, some soil series. The array of plant species is probably similar to that found on soil series.

Table 4. Representative soil features

Table 5. Representative soil features (actual values)

Other references

DEFINITIONS

These definitions have been greatly simplified for brevity and do not cover every aspect of each topic.

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

Alluvial: Materials or processes associated with transportation and/or deposition by running water.

Aquic soil moisture regime: A regime in which the soil is free of dissolved oxygen because it is saturated by water. This regime typically exists in bogs or swamps.

Aquisalids: These are salty soils in wet areas. Although wet, the dissolved salts make the soils physiologically dry (the chemical activity, or effective concentration, of water is low). Aquisalids typically support plant species that are adapted to these conditions.

Aridic soil moisture regime: A regime in which defined parts of the soil are, in normal years, dry for more than half of the growing season and moist for less than 90 consecutive days during the growing season. In Hawaii it is associated with hot, dry areas with plants such as kiawe, wiliwili, and buffelgrass. The terms aridic and torric are basically the same.

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.

Basal area or basal cover: The cross sectional area of the stem or stems of a plant or of all plants in a stand.

Blue rock: The dense, hard, massive lava that forms the inner core of an aa lava flow.

Bulk density: the weight of dry soil per unit of volume. Lower bulk density indicates a greater amount of pore space that can hold water and air in a soil.

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.

Gleyed: A condition of soil from which iron has been reduced (in the redox chemistry sense) and removed during soil formation or that saturation with stagnant water has preserved a reduced state. If iron has been removed, the soil is the color of uncoated sand and silt particles. If iron is present in a reduced state, the soil is the color of reduced iron (typically bluish-gray). Redox concentrations (spots of oxidized iron, formerly called mottles are often present.

Hydrous: A “soil texture modifier” for volcanic ash soils having a water content at the crop wilting point of 100 percent or more; a soil that holds more water than “medial” or “ashy” 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.

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

Isomesic soil temperature regime: A regime in which mean annual soil temperature is 47 degrees F (8 degrees C) or higher but lower than 59 degrees F (15 degrees C) and mean summer and mean winter soil temperatures differ by less than 11 degrees F (6 degrees C) at a specified depth.

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.

Kipuka: An area of land surrounded by younger (more recent) lava. Soils and plant communities within a kipuka are older than, and often quite different from, those on the surrounding surfaces.

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.

Mollisols: Soils with relatively thick, dark surface horizons, high cation-exchange capacity, high calcium content, that do not become hard or very hard when dry. Mollisols are conducive to plant growth. They characteristically form under grass in climates that are seasonally dry but can form under forests.

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.

Perudic soil moisture regime: A very wet regime found where precipitation exceeds evapotranspiration in all months of normal years. On the island of Hawaii, this regime is found on top of Kohala and on parts of the windward side of Mauna Kea.

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.

Psamments: Sandy soils that have low water-holding capacity, are susceptible to wind erosion, and typically have ground water deeper than 20 inches (50 centimeters).

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.

Torric soil moisture regime: See Aridic soil moisture regime.

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

Udic soil moisture regime: A regime in which the soil is not dry in any part for as long as 90 cumulative days in normal years, and so provides ample moisture for plants. In Hawaii it is associated with forests in which hapuu (tree ferns) are usually moderately to highly abundant.

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.

OTHER REFERENCES

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Allen, M.S., 2014. Marquesan colonization chronologies and post colonization interaction: implications for Hawaiian origins and the ‘Marquesan Homeland’ hypothesis. Journal of Pacific Archaeology, 5(2), pp.1-17. Discussions of earliest Polynesian migrations to Hawaii.

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Brown, James K.; Smith, Jane Kapler, eds. 2000. Wildland fire in ecosystems: effects of fire on flora. Gen. Tech. Rep. RMRS-GTR-42-vol. 2. Ogden, UT: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. 257 p. General discussion of effects of fire impacts on composition, structure, and pattern of vegetation on the landscape.

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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 Maui.

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 land use along a climatic transect. Specific to Kohala, Island of Hawaii, but information can be generally applied to Maui.

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 Maui.

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 Maui.

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.

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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.

Dudley BD, RF Hughes and R Ostertag. 2014. Groundwater availability mediates the ecosystem effects of an invasion of Prosopis pallida. Ecological Applications 24(8): 1954-1971.

Gallagher T and M Merlin. 2010. Biology and Impacts of Pacific Island Invasive Species. 6. Prosopis pallida and Prosopis juliflora (Algarroba, Mesquite, Kiawe) (Fabaceae). Pacific Science 64(4): 489-526. Doi: 10.2984/64.4.489. Discussion of the survival adaptations (phreatophyte) of Kiawe, its population biology mechanisms (recruitment, dispersal, establishment, survival), known control methods, and how it is affected by fire.

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.

Gil CR. 2016-2017. Ananas comosus. Colegio Bolivar Agricultural Science. Available online at: https://www.colegiobolivar.edu.co/garden/wp-content/uploads/2017/06/Crosas-Ananas-comosus-2017.pdf Discusses effects of pineapple monoculture on soil condition.

Handy ESC Handy EG and Pukui MK. 1972. Native Planters in Old Hawaii Their Life, Lore, and Environment. (Revised Edition, 1991). Bernice P. Bishop Museum Bulletin 233. Honolulu. Hawaiian understanding of climate, weather and seasons.

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.

Juvik JO and D Nullet. 1993. Relationships between rainfall, cloud-water interception, and canopy throughfall in a Hawaiian montane forest. IN: Tropical Montane Cloud Forests. Proc. Int. Sym., San Juan, PR. Hamilton LS, JO Juvik, and FN Scatena, eds. East-West Center. Field study of fog drip on Mauna Kea.

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 Maui.

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.

Leopold LB. 1949. The interaction of trade wind and sea breeze, Hawaii. Journal of Meteorology 6: 312-320. Study of the naulu winds that operate on the west slope of Haleakala.

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.

Lincoln, NK; Rossen, J; Vitousek, P; Kahoonei, J; Shapiro, D; Kalawe, K; Pai, M; Marshall, K; Meheula, K. 2018. "Restoration of ‘Āina Malo‘o on Hawai‘i Island: Expanding Biocultural Relationships" Sustainability 10, no. 11: 3985. https://doi.org/10.3390/su10113985

Malo, David. 1903. Hawaiian Antiquities. N.B. Emerson (trans.). Bishop Museum Special Publication 2. Honolulu. Hawaiian understanding of climate, weather and seasons.

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 Maui.

Mubyana T. 1997/98. Effects of continuous sugarcane and pineapple cropping on organic matter and soil microbial biomass. Journal of African Research and Development 27&28:258-269. Comparison of effects of pineapple cropping on soils compared with sugarcane and virgin uncropped soils. Pineapple cropping decrease pH, exchangeable cations, OM, biomass C, and flush of N.

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.

Sanderson, M (ed.). 1993. Prevailing Trade Winds, Weather and Climate in Hawaii. University of Hawaii Press. Honolulu. Hawaiian understanding of climate, weather and seasons.

Schroeder TA. 1981. Characteristics of local winds in northwest Hawaii. Journal of Applied Meteorology 20: 874-881. Study of naulu winds in Kohala, Island of Hawaii.

Sherman LA and KR Brye. 2019. Soil chemical property changes in response to long-term pineapple cultivation in Costa Rica. Agrosystems, Geosciences and Environment. Available online at: https://acsess.onlinelibrary.wiley.com/doi/full/10.2134/age2019.07.0052 Discusses deleterious effects of pineapple cultivation on soil chemical properties.

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.

Stone CP, SW Smith and JT. Tunison. 1992. Fire and Alien Plants in Hawaii: Research and Management Implications for Native Ecosystems. University of Hawaii Cooperative National Park Resources Studies Unit. Honolulu, Hawaii.

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.

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.

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.

USDI-USGS. 2006. Assessment of Invasive Plant Species Distributions on Haleakala Ranch, East Maui. Price J and JD Jacobi. USGS Hawaii Cooperative Studies Unit, Pacific Aquaculture and Coastal Resources Center, University of Hawaii at Hilo. Discussion and mapping of occurrences of important invasive plant species on Haleakala Ranch, west face of Haleakala.

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 Maui.

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.

Wilmshurst, J.M., Hunt, T.L., Lipo, C.P. & Anderson, A.J. 2011. High-precision radiocarbon dating shows recent and rapid initial human colonization of East Polynesia. Proceedings of the National Academy of Sciences, USA, 108:1815–1820. Discussions of earliest Polynesian migrations to Hawaii.

Contributors

John Proctor
Carolyn Wong
Mike Kolman
Mathew Cocking
Joe May
Lori Metz
Kendra Moselely
Amy Koch
Michael Constantinides
David Clausnitzer
Jennifer Higashino

Approval

Kendra Moseley, 5/08/2025

Acknowledgments

Assistance, advice, review, and/or insights:

Elena Dosamantes, NRCS
Darren Pinnegar, NRCS
Jamin Johanson, NRCS
Tyler Annetts, NRCS
Kekai Kapu
Randy Bartlett, Puu Kukui Watershed Preserve
Alison Cohan, The Nature Conservancy
Kristin Almasin, Ulapalakua Ranch
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
Jason Hew, NRCS
Pulelehua Kimball, NRCS
Jennifer Higashino, USFWS and 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