Pioneers crossing the US Southwest over a century ago were often slowed in their progress by great fields of thorny cactus. Today, commercial harvest, land development, and ranching practices are threatening to wipe out some species of the once plentiful desert plant, botanists warn.
"Some species you could pick forever with little impact," says Joseph Dowhan, a botanist with the US Fish and Wildlife Service.But he warns that "several species are apt to become extinct in the near future."
Big Bend National Park in southwestern Texas has been particularly hard hit by poachers. "They come in on burros and clean out everything within 100 yards of the trail," says John Pearson of the Big Bend Natural History Association. Removing plants from federal property is illegal.
Most of the plants are shipped to other parts of the country. The sale of cactuses as houseplants has become a booming business and some observers believe a major portion of them come from the wild.
Some 21 species of cactus are already protected under the Endangered Species Act from international and interstate commerce. Also, the United States is party to an international treaty that regulates the export of any species of cactus.
But that is not enough, assert botanists like Mr. Dowhan. The US Fish and Wildlife Service wants to add 69 more species to the list of endangered or threatened cactuses. Dowhan also urges stronger state laws for protection of native plants. California, Arizona and New Mexico have such laws, but Texas does not.
Faith Campbell of the Natural Resources Defense Council, a Washington research and lobbying group, says putting cactuses on the endangered species list is only a partial answer. "We need a program to control collection before a species becomes endangered," she says. This might include stringent state controls limiting the number of cactus plants that can be harvested from the wild.
Environmentalist groups have pushed for including plants in the Lacey Act, which now only protects wildlife. Expanding the federal law would mean that any violation of a state law protecting a plant species would carry a federal penalty once the plant was sold in the interstate market.
An effort to protect native plants in Texas failed in the last state legislature and some conservationists are not optimistic about a law passing this year. A botanist with the Texas Parks and Wildlife Dev partment concedes "there is a legitimate reason for concern" about some species of cactus. But he sees little evidence of political support for protecting cactus in Texas.
Arizona has what many consider an exemplary program for protecting cactus and other native plants. Seven full-time enforcement officials help prevent illegal collection of cactus. Still, director of compliance Richard Countryman says the illegal cactus trade is "big business" in Arizona. Some 90 arrests for illegal trafficking in plants were made last year, most of them dealing with cactuses.
Many of the cactuses sold in Arizona as houseplants come from Texas. Shipments as large as 70,000 plants come into the state, and the practice is perfectly legal as long as the plants are not on the federal endangered species list.
Bel Weniger, a botanist at Our Lady of the Lake College in San Antonio, says cactuses are also threatened in western Texas by the loss of habitat. Construction goes on without any attention to protecting native plants, and ranchers increasingly are clearing land with herbicides that destroy cactus, he claims. Cactus has long been a nuisance to ranchers and can be dangerous to grazing cattle.