CHAPTER 4
ENDANGERED PLANTS AND ECOSYSTEMS

Well over half the threatened and endangered species listed with the U.S. Fish and Wildlife Service are plants. There are a total of 714 threatened and endangered flowering plants (713 U.S. species, 1 foreign species), 5 threatened and endangered conifers and cycads (3 U.S. species, 2 foreign species), 26 listed ferns and allied species (all U.S.), and 2 listed lichen species (both U.S.). Listed U.S. species are shown in Table 4.1, which lists flowering plants, and Table 4.2, which lists endangered conifers, ferns, and lichens. Because the status of most plant species has not been studied in detail, many more plants are probably in danger of extinction than appear on these lists.

Many factors contribute to the endangerment of plant species. Numerous species are the victims of habitat loss due to land and agricultural development. Others have declined due to pollution or habitat damage, or as a result of competition with invasive species. Still others have succumbed to introduced plant diseases. Finally, collectors or dealers often illegally seek rare, showy, or unusual plants, and have depleted populations through over-collection.

The preservation of plant species is important for many reasons. Not only are plants of aesthetic value, they are crucial components of every ecosystem on earth. Plants also serve several functions directly beneficial to humans. First, they provide genetic variation that is used in the breeding of new crop varieties—native plants provide genes that allow for adaptation to local environments, as well as resistance to pests, disease, or drought. In addition, plants are the source of numerous human medicines.

PLANTS IN DECLINE

The 1997IUCN Red List of Threatened Plants from the World Conservation Union represents the first global assessment of plants, and was the result of over 20 years of study by botanists, conservation organizations, botanical gardens, and museums around the world. It revealed that 12.5 percent—one of every eight—of the world's plant species are in danger of extinction. In the United States, the figure is even higher, with 29 percent of the nation's 16,000 plant species threatened. Other findings included:

• Of the estimated 270,000 known species of vascular plants (ferns, conifers, and flowering plants, but not mosses, lichens, and algae), 33,798 species are in danger of extinction.
• Of the plant species at risk, 91 percent are found only in a single nation. These species are particularly vulnerable, having only limited options for recovery.
• Many plant species known to have medicinal value are at risk of disappearing. For example, 75 percent of species in the yew family, a source of cancer-fighting compounds, are threatened. Twelve percent of the willow family, from which aspirin is derived, are threatened.
• About 33 percent of the dipterocarps, a tree group that includes valuable timber species in Asia, are threatened.
• The loss of each species causes a loss of genetic material that could be used to produce stronger, healthier crops for human and animal consumption.
• Close relatives to many familiar plants are at risk of extinction, including 14 percent of the rose family and 32 percent of lilies and irises.
• Numerous species whose value has not yet been studied are at risk.

According to the 1997 IUCN Red List of Threatened Plants, the primary reasons for plant endangerment are habitat loss and introduction of invasive species. The ten areas with the greatest percentage of threatened flora are St. Helena (41.2 percent), Mauritius (39.2 percent), Seychelles (31.2 percent), the United States (29 percent),

Jamaica (22.5 percent), Turkey (21.7 percent), Spain (19.5 percent), French Polynesia (19.5 percent), Pitcairn (18.4 percent), and Reunion (18.1 percent). Note that islands are disproportionately represented in the top ten. This is primarily because islands are particularly vulnerable to invasive species.

However, the 1997IUCN Red List of Threatened Plants contains regional biases—assessments of flora in North America, Australia, and Southern Africa were more comprehensive than those for other regions. It is likely that significantly greater numbers of threatened plant species will be found in Asia, the Caribbean, South America, and the rest of Africa when these areas are fully studied.

Information from the 1997 IUCN Red List of Threatened Plants is being incorporated into new versions of IUCN publications. The 2003 IUCN Red List of Threatened Species currently lists 6,774 species of threatened plants. This is almost 70 percent of the 9,706 that have been examined. However, only about 4 percent of plant

species have been studied in sufficient detail to assess their status, and the actual number of threatened species is likely to be very much higher.

The majority of IUCN-listed species are flowering plants, a diverse and well-studied group. In 2003 the IUCN reported that 6,279 of 8,526—or 74 percent of—flowering

plants were threatened. Among coniferous plants, 152 species, or 25 percent of the total, are threatened. Other IUCN-listed species include 36 true mosses (92 percent of species studied), 11 club mosses (85 percent of species studied), 42 liverworts (81 percent of species studied), 98 true ferns (60 percent of

species studied), and 151 cycads (52 percent of species studied).

Habitat loss accounts at least in part for the threatened status of 91 percent of IUCN-listed plants. The greatest number of threatened species are found in Central and South America, Central and West Africa, and Southeast Asia. Countries with the largest number of listed plants include Malaysia (681 species), Indonesia (384 species), Brazil (338 species), and Sri Lanka (280 species). Many of the threatened species from these countries represent tropical timber trees.

THE AMERICAN LANDSCAPE

Although North America has less plant diversity than the tropics, it is nonetheless amazingly rich. The diverse environmental conditions found on the continent allow representatives of most of the world's major plant groups to flourish in one region or another. For example, North America is home to more than 211 flowering plant families alone. The richest assemblages of flowering plants are found in Florida and Texas.

Botanists have divided North America into a series of ecosystems based on the underlying vegetation. Northern coniferous forests make up 28 percent of the North American continent; grasslands, 21–25 percent; arctic ecosystems, 19 percent; eastern deciduous forests, 11 percent; coastal plain ecosystems, 3 percent; desert ecosystems, 5 percent; western mountain coniferous forests, 7 percent; tidal wetlands, 1 percent; Mediterranean scrublands and woodlands, 1 percent; and beach vegetation, less than 1 percent.

Endangered U.S. Ecosystems

In 1995 the first full review of the health of the American landscape, "Endangered Ecosystems of the United States—A Preliminary Assessment of Loss and Degradation," was compiled by the National Biological Service (NBS) and published by the U.S. Geological Survey. It is still considered the definitive study of U.S. ecosystem health. Although individual species had been studied previously,

the health of the larger ecosystems had never before been considered. The study was based on surveys of state databases and the scientific literature. The report concluded that vast stretches of natural habitat, totaling nearly half the area of the 48 contiguous states, had declined to the point of endangerment. Ecosystems suffered in two ways. Quantitative losses were measured by a decline in the area of an ecosystem. Qualitative losses involved degradation in the structure, function, or composition of an ecosystem.

Of the ecosystems that had declined by over 70 percent, 58 percent were terrestrial, 32 percent were wetland areas, and 10 percent were aquatic. Forests, grasslands, barrens, and savannas dominated the list. (See Figure 4.1.) American ecosystems identified by the NBS as suffering the greatest overall decline include tall-grass prairies and oak savannas of the Midwest, deciduous forests of the East, and longleaf pine forests of the southern coastal plains. The midwestern prairies have been all but destroyed through conversion to agriculture—the original extent of these prairies is shown in Figure 4.2. As ecosystems shrink, the species that live in them become imperiled as well. The longleaf pine ecosystem of the southern coastal plain, for instance, is home to 27

species on the Endangered Species List and another 99 species that have been proposed for listing.

The full NBS list of the most endangered ecosystems of the United States appears in Table 4.3. Thirty-two American ecosystems had declined by more than 98 percent and were classified as "critically endangered." Fifty-eight had declined by 85 to 98 percent and were classified as "endangered." Thirty-eight others declined by 70 to 84 percent and were listed as "threatened."

Endangered ecosystems were found in all major regions of the United States except Alaska. The greatest losses occurred in the Northeast, the South, and the Midwest, as well as in California. A list of some Californian plant communities, most of which are unique to the state, and percentage reductions in these community types appear in Table 4.4. Native grasslands, needlegrass steppes, and alkali sink scrubs are among the communities that have declined most precipitously in California.

Endangered ecosystems are linked to many federally listed threatened and endangered species. Table 4.5 shows the endangered, threatened, proposed, and candidate species that are found in old-growth forests in the Pacific Northwest. Although the northern spotted owl has become linked to this region in the minds of many, these forest habitats are essential to numerous other endangered species. Table 4.6 provides a similar list for the endangered coastal sage scrub ecosystem in California. Table 4.7 lists species associated with the critically endangered longleaf pine and wiregrass communities of the southern coastal plain (which includes parts of North and South Carolina, Georgia, Florida, Alabama, Mississippi, and Louisiana).

Hawaiian Plants

Because of its isolation from continental land masses, many of the species found in Hawaii exist nowhere else in

the world. An estimated 90 percent of Hawaiian plant species are in fact endemic. Because of large-scale deforestation and habitat destruction on the Hawaiian islands, Hawaii is home to more endangered plants than any other state in the nation, with 312 listed species in 2004. Hawaiian plants have suffered from the introduction of invasive predators such as cows, pigs, and insects, as well as the loss of critical pollinators with the decline of numerous species of native birds and insects. Over 10 percent of Hawaiian plant species have gone extinct in the last few hundred years, and nearly 30 percent are currently believed to be imperiled.

In April 2002, a major step in protecting Hawaii's endemic flora was taken when the Fish and Wildlife Service

proposed critical habitat for native plant species on the islands of Maui and Kahoolawe. The proposal includes fifteen habitat areas covering approximately 128,000 acres. Protection of these areas would benefit at least 61 threatened and endangered species by preserving current habitat, as well as allowing for natural range expansion and the reintroduction of endangered species into portions of their historic ranges. The areas proposed for critical habitat include Hawaii state lands (45 percent), federal lands (17 percent), and privately owned land (37 percent). Only activity on federal lands is legally affected by critical habitat designation.

In July 2003 the Fish and Wildlife Service designated over 208,000 acres of critical habitat on the island of Hawaii (Big Island) as habitat for forty-one listed plant species. The area designated was 52 percent smaller than originally anticipated because it excluded a large tract of U.S. Army land as well as private land held by the Queen Liliuokalani Trust and others. The U.S. Army land was excluded because of national security concerns and because the Army agreed to voluntarily cooperate with the Fish and Wildlife Service regarding activity that affects endangered species. The Queen Liliuokalani Trust land was excluded because the trust vowed to discontinue its current efforts on behalf of endangered species if its lands were included in the critical habitat designation. Finally, land near the cities of Kailua and Kona, for which housing development was planned, was excluded from critical habitat designation because the economic and social costs of inclusion were too great.

Designation of critical habitat in Hawaii was completed after a successful lawsuit brought against the Fish and Wildlife Service by Earthjustice, the Conservation Council for Hawaii, the Sierra Club, and the Hawaii Botanical Society.

Profiles of Some Endangered North American Plants

ENDANGERED CACTI.

Over thirty cactus species are currently listed with the U.S. Fish and Wildlife Service as either threatened or endangered. Most of these species are found in arid habitats in the Southwest, particularly Texas,

New Mexico, Arizona, and Utah. In addition to habitat loss and degradation, a prime reason for the endangerment of cactus species in general is over-collection by enthusiasts.

The star cactus is a spineless species found in Texas and parts of Mexico, and was listed as endangered across its entire range in 1993. In Texas, it is found only along a

single creek system in Starr County. The star cactus is several inches in diameter and only a few inches tall. The flowers have large yellow petals that form a deep bowl. Endangerment of this species resulted partly from over-collection in the wild by cactus enthusiasts, who greatly prize it. The star cactus has also suffered from habitat loss due to urban and agricultural development. The San Antonio Botanical Garden has attempted to aid conservation efforts by developing methods for propagating this species from seed.

The bunched cory cactus was first listed as threatened in 1979. It is a small species, reaching heights of up to four inches. The bunched cory cactus has rounded, single stems and occupies ledges and flats on limestone outcrops. Populations occur in Big Bend National Park in Texas, as well as on some private ranches—a total of approximately 25 different sites are known. Despite strict regulations against collection and monitoring in park sites, cactus poachers nonetheless continue to collect the plant illegally.

SHOWY STICKSEED.

Showy stickseed is one of the most recent plants to be added to the Endangered Species List. It was officially listed in February 2002 as endangered throughout its habitat—a single site in the Wenatchee National Forest in Chelan County in the state of Washington. Showy stickseed was once observed at a second site in Chelan County but is now believed to be extinct there. Approximately 1,000 showy stickseed plants existed in the early 1980s, but only 500 plants were found in a 2001 survey. Critical habitat was not designated for showy stickseed by the Fish and Wildlife Service because it was believed to be imprudent to reveal the location of the sole population for fear of illegal collection.

Showy stickseed is an herb eight to sixteen inches tall. When in bloom, it has large, white flowers. Endangerment is believed to have resulted from competition with invasive species such as weeds, woody shrubs, and trees. Showy stickseed requires large amounts of sunlight, which has become increasingly blocked by the larger invasive species. A long history of fire suppression has also contributed to the shading problem. The other major factor contributing to endangerment of this species is collection from the wild. Now that the species is listed under the Endangered Species Act, collection is considered a federal crime. The Fish and Wildlife Service is cooperating with the Wenatchee National Forest and the Washington Department of Transportation to help improve habitat areas for the showy stickseed. This includes thinning of invasive tree species and control of weeds. In addition, experimental propagation of the stickseed is being pursued.

DESERT YELLOWHEAD.

In March 2002, the desert yellowhead was listed as threatened in its only known habitat, 50 acres of federal land in Wyoming. There were about 12,000 plants found in a survey conducted in 2001. The desert yellowhead is related to sunflowers, and has twenty-five to eighty flowers crowded atop each twelve-inch stem. The species was first discovered in 1990. The desert yellowhead is threatened due to human activity. Portions of its current habitat are being considered for oil and gas drilling. The Fish and Wildlife Service is working with the Bureau of Land Management, which manages desert yellowhead habitat, on a conservation plan.

ROBBINS' CINQUEFOIL.

The Robbins' cinquefoil was officially listed as endangered in 1980. This plant species is related to roses, and is found in the alpine zone of the White Mountain National Forest in New Hampshire. It is a small species that bears a yellow flower. At the time of listing, there were approximately 3,700 plants surveyed. After concerted conservation efforts involving the Fish and Wildlife Service, the U.S. Forest Service, and the Appalachian Mountain Club, the population of the Robbins' cinquefoil increased to over 14,000 plants in 2001. In June 2001, the species was proposed for delisting. Critical actions that helped the population recover included a rerouting of the Appalachian Trail around the critical habitat areas of the species, as well as the building of an enclosure to protect the population from disturbance. In addition, two populations of Robbins' cinquefoil were introduced in new National Forest habitats.

LOS ANGELES BASIN MOUNTAIN PLANTS.

Numerous species of threatened and endangered plants have reached their precarious state due to urbanization and other human activity. Figure 4.3 shows the species distribution of six threatened and endangered plant species found in the mountains surrounding the Los Angeles basin. The recovery plan for these species lists current threats to species survival as including: "urban development, recreational activities, alteration of fire cycles, fire suppression and pre-suppression (fuel modification) activities, over-collecting, habitat fragmentation and degradation, and competition from invasive weeds." Some species are currently so reduced in number that extinction due to random events is also a threat.

MEAD'S MILKWEED.

Mead's milkweed is a federally listed threatened species with populations in Kansas, Missouri, Iowa, and Illinois. The species has already gone extinct in Wisconsin and Indiana. Most population loss is attributed to agriculture. Figure 4.4 shows the counties where Mead's milkweed currently persists, counties where it once existed but is now extinct, and counties where reintroductions into suitable habitat are taking place. Table 4.8 lists the summary of threats to Mead's milkweed as well as the recommended recovery actions that appeared in the species recovery plan, published in September 2003 by the Fish and Wildlife Service.

ENDANGERED FORESTS

Forests perform a wide variety of social and ecological functions. They provide homes and sustenance for forest dwellers, protect and enrich soils, affect local and regional climate through the evaporation and storage of water, and help stabilize the global climate by processing carbon dioxide.

Forests are broadly classified by latitude as either tropical, temperate, or boreal. Tropical forests, or rainforests, are predominantly evergreen and occur close to the equator, in areas with plentiful rain and little temperature variation year-round. There are tropical forests in Central and South America, Africa, South and Southeast Asia, and Australia. Tropical forests are characterized by the greatest diversity of biological species. For example, as many as one hundred distinct tree species may inhabit a square kilometer. Vegetation is often so dense in tropical forests that very little light penetrates to the ground. Temperate forests are found in areas with distinct warm and cold seasons, including North America, northern Asia, and western and central Europe. Many temperate forests are made up of deciduous trees—species that shed their leaves during winter. Plant diversity is not as great in temperate forests as in rainforests. There are perhaps three or four tree species per square kilometer. Boreal forests, also known as taiga, are found at high latitudes in extremely cold climates where the growing season is short. Precipitation generally falls as snow rather than rain. Boreal forest flora includes evergreen trees and lichen ground cover. Boreal forests are present in Siberia, Scandinavia, Alaska, and Canada.

Deforestation

Deforestation refers to the destruction of forests through the removal of trees, most often by clear-cutting or burning. It results in habitat loss for countless species of plants as well as animals. Deforestation is occurring globally, but is proceeding at a particularly alarming rate in the world's tropical rainforests, which comprise the most diverse ecosystems in the world. Deforestation is one of the most pressing environmental issues today.

In addition to destruction of habitat for numerous plant and animal species, the loss of forests has other effects as well. For example, forests play a crucial role in the global cycling of carbon—vegetation stores two trillion tons of carbon worldwide, roughly triple the amount stored in the atmosphere. When forest trees are cleared, the carbon they contain is oxidized and released to the air, adding to the carbon dioxide in the atmosphere. The burning of the Amazon rainforests and other forests thus has a two-fold effect—the release of large amounts of carbon dioxide into the atmosphere and the loss of the trees that help absorb carbon dioxide.

Furthermore, deforestation also results in forest fragmentation, which is itself detrimental for several reasons. First, forest fragmentation creates more "edge" habitats and destroys habitat for deep-forest creatures. Second, fragmentation isolates plant and animal populations, making them more vulnerable to local extinction. Third, some non-native species thrive in edge habitats, and are able to invade and displace native species in a fragmented habitat. In North America, for example, songbirds like the wood thrush and the promontory warbler are declining due to increasing numbers of blue jays and parasitic brown-headed cowbirds, both of which flourish at forest edges. Finally, most trees are more susceptible to weather at forest edges.

Rainforests

Tropical forests are the world's most biologically rich habitats. These storehouses of biological diversity cover less

than 1 percent of the earth, but are home to 50 to 90 percent of the world's species. Many rainforest species have yet to be discovered and described by humans. In May 2002 for example, ornithologists announced the discovery of a new species of parrot, described as possessing green feathers, a hooked neck like a vulture, and a bald orange head. If new discoveries are being made even among well-studied groups such as birds, one can only imagine the untold number of insects or plants that remain to be studied.

Tropical forests are also the most critically endangered of habitats and are shrinking faster than ever—about 42 million acres a year are lost, or 80 acres each minute. The primary threats to rainforests are logging and clearing for farms and ranches. Satellite photographs show that as much as 10 percent of the Amazon rainforest has been destroyed, mainly through "slash and burn" clearing for agricultural use. Conservative estimates suggest rates of decline as high as 6.5 percent per year for rainforests in the Cote d'Ivoire in Africa, and an average of 0.6 percent per year for all tropical forests. At this pace, all rainforests will be cleared within 177 years. Given the growth in human population and economic activity in developing countries, the rate of deforestation is more likely to increase than to stabilize. Losses have been greatest so far in West Africa, Brazil, Central America, Mexico, Southeast Asia, and Madagascar.

The major underlying causes of tropical deforestation are underdevelopment, unemployment, and poverty among the growing populations of tropical countries. Unrestricted by enforceable regulations, farmers clear forests to create meager cropland that is often useless three years after its conversion—this is because tropical forest soils are poor, because almost all available nutrients are locked up in the trees and other biomatter. Logging and the conversion of forestland to unsustainable, short-term agricultural use have resulted in the destruction of habitats, declining fisheries, erosion, and flooding. Forest loss also disrupts regional weather patterns and contributes to global climate change. Finally, it eliminates plant and animal species that may serve important medical, industrial, and agricultural purposes. However, arguments for protective measures that might not pay off for many decades are often of little interest to farmers with families to feed. Developing countries frequently voice resentment over what they see as the hypocrisy of industrialized nations, which invariably engaged in similarly destructive practices to build their own economies.

Conservation of tropical forests presents a considerable challenge. The creation of "protected areas" alone has often proven ineffectual, mostly because the people who exploit forests are given no other options for meeting their economic needs. Many conservationists have started

to focus on the promotion of sustainable development within rainforests. Agroforestry describes an agricultural strategy that involves the maintenance of diversity within developed tropical forest areas. This includes planting many different types of crops in patches that are mixed in among grazing lands and intact forest. Agroforestry often focuses on crops that produce goods for an indefinite period of time, including citrus fruits, bananas, cacao, coffee, and rubber.

Agroforestry can help to maintain soil quality as well as tropical biodiversity, allowing for a sustained productivity that makes it unnecessary to clear more and more areas of forest. In addition, rainforest conservationists have promoted the harvest of sustainable rainforest products, rather than unsustainable products such as timber. Sustainable harvests include those of medicines, food, and rubber.

Finally, a recent trend is certification of tropical timber. It is estimated that as much as 70 percent of tropical timber available for sale in the United States represents "stolen timber" obtained through illegal logging. The Forest Stewardship Council, based in Oaxaca, Mexico, runs a program that certifies timber obtained from forests managed as sustainable environments. Large wood suppliers, such as Home Depot in 1999, opted to give preference to certified wood by 2002 following extensive picketing by protesters at several stores.

North American Forests

In 2003, the U.S. Forest Service reported that the United States has a total of 747 million acres of forestland. Of these, 20 percent belong to the National Forests, 13 percent are controlled by other federal agencies, 8 percent are owned by states, 49 percent are held by nonindustrial landowners, and 10 percent are held by industrial landowners.

Many U.S. forests are highly imperiled. One of the greatest threats to forests is deforestation via clear cutting, a method of logging in which all the trees in an area are cut. Serious damage to the old-growth forests of the Pacific Northwest, for example, is visible from National Aeronautics and Space Administration (NASA) satellite photos. Old-growth forests harbor many unique species, including numerous species that are threatened or endangered. An alternative to clear-cutting is selective management, in which only some trees are removed from an area. Even selective management practices, however, frequently deplete forests more quickly than they are able to recover. The lumber industry continues to battle with environmentalists and the U.S. Forest Service over the right to log National Forest lands, including the unique redwood forests of the West Coast. (See Figure 4.5.)

Huge forest fires raged through the western United States in 2000 and 2002. The Forest Service reported that these were two of the worst fire seasons in over fifty years. In 2002 forest fires scorched over 7 million acres and caused over $1.7 billion in damages. The fires were partly the result of long decades of fire suppression. In response, President Bush announced the "Healthy Forest Initiative" in 2002. This initiative was immediately attacked by conservationists, who claimed that its only aim was to roll back federal regulations on logging, and that it was intended to benefit logging companies rather than to protect people or wildlife. Conservationists further argued that the Bush Administration was merely using the forest fires as an excuse for forwarding its pro-business/anti-environment agenda.

In addition to logging and fire risk, the Forest Service highlighted several other major threats to forests in its 2003 forest health update. These include:

• Invasive insects and pathogens. Sudden Oak Death, caused by a new, unidentified pathogen, has killed thousands of oak and other species in coastal forests, mixed evergreen forests, and urban-wildland interfaces in California and southern Oregon. White Pine Blister Rust is a non-native fungus from Asia that has killed white pine trees in the western United States and Canada. The gypsy moth, first introduced from native habitats in Europe and Asia in the 1800s, continues to damage eastern U.S. forests. The hemlock woolly adelgid, native to Asia and introduced in the 1920s, continues to kill hemlock trees in the eastern United States.
• Invasive plants. About 1,400 species of non-native plants are recognized as pest species that threaten forests and grasslands. Invasive plant species currently affect over 100 million acres of U.S. forestland. The Forest Service spends about $16 million annually in preventing the spread of invasive plants such as the "mile a minute" weed, which infests northeastern forests, and leafy spurge, which affects ecosystems in southern Canada and the northern United States.
• Outbreaks of native insects. Certain native insects, including bark beetles, mountain pine beetles, and southern pine beetles, can also lay waste to native forests when they occur in large outbreaks.

TONGASS NATIONAL FOREST.

During the first millennium a.d., an expanse of ancient forest flourished along the entire western coast of the United States and Canada. Today, a portion of this habitat, a 500-mile expanse along the southeastern coast of Alaska, has been preserved as Tongass National Forest. Tongass National Forest represents an unblemished stretch of trees and other wildlife that has existed as a completely intact ecosystem for over a thousand years. It includes 17 million acres of pristine woodland and has never experienced an extinction in modern times. The Tongass preserve comprises 26 percent of the world's temperate rainforest and is the largest on earth.

In the mid-twentieth century, however, the federal government began to negotiate with logging companies to open small portions of the ancient forest for clear-cutting. This has generated ongoing debate in Congress. In the 1990s loggers appealed to the government to open more access roads to facilitate logging, whereas environmentalists fought to preserve the area from human tampering altogether. In May 2000 the National Forest Service drafted a proposal urging renewed protection of roadless areas. A lawsuit brought by the Natural Resources Defense Council in 2003 succeeded in protecting Tongass and other roadless national forests from logging. The Bush Administration exempted Tongass from these protections and is attempting to open 2.5 million acres of the forest to logging.

WETLANDS

Wetlands are transitional areas between land and water bodies where water periodically floods the land or saturates the soil. The term wetland includes environments such as marshes, swamps, bogs, and estuaries. Wetlands may be covered in shallow water most of the year or be wet only seasonally. Plants and animals found in wetlands are uniquely adapted to these conditions.

Wetlands in the United States are highly diverse because of regional differences in climate, geology, soils, and vegetation. There are approximately 105.5 million acres of wetlands in the country. The majority of this is freshwater wetland (95 percent, or 100.5 million acres). The rest is tidal, or saltwater, wetland and is found along the coasts. Wetlands are found in nearly all states—there are arctic tundra wetlands in Alaska, peat bogs in the Appalachians, and riparian (riverbank) wetlands in the arid west. Table 4.9 lists some of the different types of wetlands and their acreage in the forty-eight contiguous United States, as well as how acreage has changed in the decade from 1986 to 1997.

As of 2004, well over half the original North American wetlands have vanished. A few states have lost nearly all their original wetlands. With the recognition of the importance of wetlands and the institution of protective measures, the pace of wetland loss has slowed in recent decades. About 58,500 wetland acres were lost each year between 1986 and 1997, with forested wetlands suffering the most damage. Although this represents an 80 percent drop from the previous decade, wetland loss is still significant. (See Figure 4.6.) The new land uses of these converted wetlands are shown in Figure 4.7. Wetlands provide critical habitats for fish and wildlife. They also purify polluted water and check the destructive power of floods and storms. Finally, wetlands provide recreational opportunities such as fishing, hunting, photography, and wildlife observation.

Endangered Bog Plants

Bogs are non-tidal wetland ecosystems that form where poor drainage and low oxygen levels combine with a low mineral content to retard the decay of organic material. Over time, peat, partially decayed organic substances, begins to solidify, forming layers over the surface of ponds. Migrating birds and amphibians, including some salamanders, are among the animals most commonly found in bog habitats. Bog flora includes coarse, grasslike plants called sedges and unusual carnivorous plants such as sundew and pitcher plants. Carnivorous plants capture and digest small insects in order to obtain nutrients unavailable in their unique environments, most often minerals such as nitrogen and phosphorus. The leaves of the sundew are covered with hundreds of tiny "tentacles" that are used to trap insects. The sundew traps an average of five insects per month. Pitcher plants maintain a pool of acidic fluid at the bottom of their "pitchers." Hairs on the inside of the pitchers point downward, preventing insects from exiting once they enter. Insects are attracted to the pitchers by the enticing red color inside.

Bog plants are threatened primarily by encroaching urbanization. Boggy wetlands are either drained or filled for use as dumping grounds. In addition, the suppression of naturally occurring fires discourages the formation of bog ecosystems. One bog species, the funnel-shaped green pitcher plant, first appeared on the Endangered Species List in 1979. Found in Alabama, North Carolina, and Georgia, it has declined largely due to collection by humans, who find these insect-eating plants both interesting and exotic. The collection of carnivorous plant species has also disrupted bog ecosystems by allowing mosquitoes and flies to proliferate.

The Florida Everglades

The Everglades covers approximately 5,000 square miles of southern Florida. It includes a wide diversity of both temperate and tropical habitat types, including saw-grass prairies, mangrove swamps, pine forests, cypress forests, marshes, and estuaries, and represents one of the wildest and most inaccessible areas in the United States. The area was formed by centuries of water flow from Lake Okeechobee in south-central Florida to Florida Bay, and is often described as a shallow "river of grass." The highest land in the Everglades is a mere seven feet above sea level. Everglades National Park is the largest remaining subtropical wilderness in the United States, and is home to endangered species such as the American crocodile, Florida panther, wood stork, and West Indian manatee. The Everglades became a National Park in 1947, and the region has also been designated an International Biosphere Reserve, a World Heritage Site, and a Wetland of International Importance.

Everglades habitats are now threatened by many factors. First, water control through an extensive system of canals and levees has brought both droughts and floods to Everglades lands. Much of the Everglades' water has traditionally been diverted for irrigation or to supply metropolitan areas. In fact, the portion of the Everglades inundated by water has been reduced drastically over the twentieth century, destroying numerous habitat areas. Occasional releases of large amounts of water, on the other hand, flood habitats, harming species such as alligators, whose nests may be washed away. Pollution is a second factor in Everglades deterioration. Harmful pollutants now found in the Everglades include fertilizers and pesticides from agricultural runoff, as well as mercury. Fertilizers encourage the rampant growth of vegetation that chokes wetlands, while pesticides and mercury poison species. One plant species that is affected is Garber's spurge, a beach herb that thrives in sandy peripheral soil. With its decline, parts of the Everglades have been more prone to soil erosion. Invasive species have also altered Everglades habitats. Alien species such as Brazilian pepper and Australian pine have reduced native plant populations. Finally, fire suppression related to human encroachment has caused habitat alteration. Park officials now adhere to a prescribed burn schedule, setting fires in three-to ten-year intervals as necessary.

Multiple efforts were made in the 1990s and early 2000s to help restore the Everglades. Florida's Everglades Forever Act, passed in 1994, attempted to limit agricultural runoff as well as set water quality standards. The Comprehensive Everglades Restoration Plan, passed by Congress in 2000, is a 38-year project drawn up by the U.S. Army Corps of Engineers. It aims to restore natural water flow patterns in the Everglades and to redirect water to the marshes. In December 2000, President Bill Clinton signed the Water Resources Development Act of 2000, which committed over $4 billion to Everglades restoration.

Tidal Wetlands—The Mangroves

Mangrove forests are among the most biodiverse wetland ecosystems on earth. They are found in tropical coastal waters, often near river mouths. The tree species found in mangrove forests possess special roots that allow them to survive in brackish water. Mangrove forests harbor numerous unique species worldwide, such as crab-eating monkeys, fishing cats, and diverse species of birds and fish. They also provide food and wood for local communities, stabilize coastlines, and provide barriers from the sea during storms. Mangrove forests once lined three-quarters of the world's tropical coasts. Now, according to the World Resources Institute, an environmental advocacy group, less than half these forests remain. Indonesia, a country of more than 13,000 islands, possesses the most mangrove forestland of any country. Brazil and Australia also have extensive mangrove habitats.

Mangroves are disappearing in part because they have traditionally been regarded as sinister, malarial wastelands. In Florida, for example, mangroves were flooded every year to control mosquito populations. Mangrove forests have also been sold to logging companies for paper pulp, pest-proof timber, and chipboard for coastal development. Many mangrove forests have also been replaced with saltwater ponds for commercial shrimp farming. The shrimp industry is perhaps the most immediate threat to mangrove forests today.

During the Vietnam War, herbicides were dumped on an estimated 124,000 hectares (approximately 306,410 acres) of mangrove forests in South Vietnam. These areas remain, for the most part, entirely barren—a true wasteland.

PLANT CONSERVATION

Protection under the Endangered Species Act

The Endangered Species Act of 1973 protects listed plants from deliberate destruction or vandalism. Plants also receive protection under the consultation requirements of the act—that is, all federal agencies must consult with the Fish and Wildlife Service to determine how best to conserve species as well as to ensure that no issued permits will jeopardize listed species or harm their habitats.

However, many conservationists believe that plants receive less protection than animals under the Endangered Species Act. First, the Endangered Species Act only protects plants that are found on federal lands. It imposes no restrictions on private landowners whose property is home to endangered plants. Critics also complain that the Fish and Wildlife Service has been slow to list plant species. Hundreds of plant species first proposed for listing in 1976 are still awaiting action. Critics also charge that damage to plant habitats is not addressed with the same seriousness as for animal species. The Fish and Wildlife Service only rarely designates critical habitat for plant species, and only rarely acquires national wildlife refuges to protect plants. Finally, of all Fish and Wildlife Service funds spent on threatened and endangered species, about half goes to a handful of listed animal species. Plants typically receive less than 3 percent of the total, and about 15 percent of plant species receive no funding at all—twice the proportion of animals that receive no funding.

In June 2000, in an effort to bolster conservation efforts for plants, the Fish and Wildlife Service announced an agreement with the Center for Plant Conservation, a national association of botanical gardens and arboreta. The two groups will cooperate in developing conservation measures to help save North American plant species, particularly those listed as threatened or endangered. Central to the effort will be the creation of educational programs aimed at informing the public about the importance of plant species for aesthetic, economic, biological, and medical reasons. The Center for Plant Conservation will also aid in developing recovery plans for listed species.

Wildcrafting

Wildcrafting describes the harvest of forest resources for profit or recreation without damaging habitat. Wildcrafting has enjoyed a resurgence since the government and courts curtailed logging on public land in the early 1990s. The wildcrafting industry brings in hundreds of millions of dollars annually.

In 1995 American exports of commercial moss and lichen alone amounted to $14 million, according to U.S. Forest Service scientists. Mushrooms—matsutakes, chanterelles, and morels—also bring good prices. Burls, hard woody growths on trees, which become unusually attractive when sanded and polished, can be used for furniture, cabinets, and trims. Ferns and shrubs for floral arrangements, Christmas greens, and more than 100 medicinal herbs are also collected.

The U.S. Forest Service, which issues permits to wildcrafters on public lands, is still examining how much wildcrafters can harvest without causing damage. Some rangers and environmentalists worry that forest products may be over-harvested, causing habitat damage, or that trampling will damage the forest floor.

Plant-Derived Medications

Numerous plant species have medicinal uses—in fact, the global market in plant-derived medications is worth $40 billion annually. Unfortunately, less than 1 percent of plant species have been evaluated for potential medical use. With as many as 50 plant species disappearing daily, botanists calculate that the planet's diversity could be reduced by 10 percent by the year 2015. Extinction will deprive future generations of potentially powerful medications. The rapid destruction of tropical rainforests is particularly alarming, as 60 percent of higher plant species occupy those ecosystems.

Between 25 and 40 percent of all prescription drugs in the United States contain active ingredients derived from plants. For example, Cinchona ledgeriana is the source of quinine, the oldest malaria medicine. The Madagascar periwinkle, found in a country that has lost 80 percent of its vegetation, provides two potent compounds used in the treatment of cancer. Vinblastine is used to treat Hodgkin's disease, and vincristine is used to treat leukemia. Sales of these two drugs exceed $180 million a year. Wild yam is the source of diosgenin (a key ingredient in some oral contraceptives), steroids, and muscle relaxants used in anesthesia. Morphine, a powerful pain medication, comes from the opium poppy. Scopolamine, a drug used for motion sickness, is derived from a plant called Hyocyamus niger. Taxol, a drug used to treat ovarian cancer, comes from the Pacific yew.

Numerous plants are also found on the non-prescription medicinal herb market. In the United States, some 175 North American species alone are available on the non-prescription market. In North America and Europe, herbal medicine markets have increased by 10 percent per year for over a decade. Examples of medicinal herbs include mullein, which is said to relieve asthma, and ginseng, which is claimed to boost vitality.

The use of medicinal plants is even greater in non-industrial societies, where large segments of the population rely on traditional medicine. Traditional healers in South Asia use nearly 2,000 plant species. Over 5,000 species are used by traditional healers in China. Over 1,300 species are used by healers in Amazonia. Furthermore, nearly 100 commercial drugs derived from plants were originally discovered by traditional healers.

Medicinal plants are declining in many areas as a result of habitat degradation and non-sustainable use. In fact, a report from the New Scientist ("Herbal medicine boom threatens plants," 8 January 2004) suggests that, of the 50,000 medicinal plants in use, two-thirds are harvested from the wild, and 4,000–10,000 of these are now endangered. Because health fads change constantly, causing demand for certain plants to change to over time, herbal remedy companies have little incentive to harvest in a sustainable way.

The African cherry, used by traditional healers in Cameroon, has declined so much due to overexploitation that the market has now collapsed. Much of the African cherry harvested had been exported to Western Europe, where the plant is used to treat prostate disease. In North America, medically valuable species such as the Pacific yew, a "trash" evergreen found in old-growth forests of the Pacific Northwest, have been cleared to make way for tree species profitable to the timber industry. The cessation of logging in the Pacific Northwest—in order to protect northern spotted owl habitat as required by the Endangered Species Act—has protected the Pacific yew as well.

In 1990 the National Institute for Biodiversity in Costa Rica entered into a landmark deal with Merck, a pharmaceutical company, in which the institute would provide rights to drug exploration, while Merck would fund tropical forest conservation and research. Tropical forests have produced at least forty-seven major pharmaceutical drugs, and scientists estimate that several hundred more plants with medicinal properties have yet to be discovered. This agreement became a model for other such arrangements. However, no deals were attempted in the United States until 1996, when the idea caught the attention of U.S. conservationists. That year Dr. James Tiedje, director of the National Science Foundation's Center for Microbial Ecology at Michigan State University, reported that a single gram of temperate forest soil could harbor as many as 10,000 species of bacteria. By 2000 a group of drug manufacturers had agreed to support a 270-acre pharmaceutical preserve in upstate New York, the first preserve outside the tropics set aside specifically for chemical prospecting. Scientists already have discovered a mold that produces a substance called cyclosporin, which is used to prevent the rejection of transplanted organs.

ECOSYSTEMS APPROACHES TO CONSERVATION

Many environmentalists are now calling for the protection of entire ecosystems, which they believe will be more effective in preserving biodiversity than focusing on individual endangered species. Ecosystem approaches consider entire communities of species as well as their interactions with the physical environment, and aim to develop integrated plans involving wildlife, physical resources, and sustainable use.

Several federal agencies have produced ecosystem-level analyses of U.S. land areas. The U.S. Forest Service has divided the U.S. into different ecoregions based on vegetation patterns. (See Figure 4.8.) The U.S. Environmental Protection Agency's National Health and Environmental Effects Research Laboratory has identified Level III ecoregions based on various factors including climate and vegetation. Figure 4.9 illustrates the Level III ecoregions for the state of Alaska. The most prominent environmental challenges in each ecoregion have also been identified. The Fish and Wildlife Service has divided the country into a series of fifty-three ecosystem units based on the location of watershed areas. (See Figure 4.10.) Each unit is associated with a team that develops a comprehensive strategy for conservation. Central to ecosystem conservation strategies is the preservation of large, intact areas of habitat.

Ecosystem approaches to conservation sometime require compromise with developers as well. This is the case for several Habitat Conservation Plans developed in recent years. In Southern California developers and environmentalists had long battled over hundreds of thousands of biologically rich acres lying between Los Angeles and Mexico that were home to uncounted species of plants and animals. Developers wanted to build there, while federal regulators wanted to protect the habitat for wildlife. Haggling over small parcels of land had already cost significant time and money and caused frustration on both sides. A compromise resolution permitted developers to develop some large parcels of land while setting aside other large, intact regions as conservation areas. A similar agreement between developers and environmentalists was reached in the Texas Hill Country. The Balcones Canyonlands Conservation Plan set aside 111,428 acres for ecosystem enhancement while allowing uncontested development of many thousands of acres of land in the central Texas corridor.