Second thoughts: Border Patrol plan to kill plants deserves re-examination

The Border Patrol's $2.1 million experiment to clear a stretch of the Rio Grande near Laredo of ground cover by spraying herbicide from helicopters has started to wither under the glare of public scrutiny before even getting off the ground. As reported by the Chronicle's Dane Schiller, the project scheduled to begin this week with test applications of the chemical imazapyr has been halted as protests mounted from the Mexican government and Texas border officials and environmentalists concerned about possible side effects of the defoliant. The idea was to use the herbicide to eliminate dense stands of carrizo cane and other vegetation that provided cover for people engaged in illegal activities along the river banks. The pilot project would test the effectiveness of cutting the cane and painting the roots with herbicide, simply digging out the cane manually, or using repeated airborne spraying to eliminate all vegetation. Native plants that do not obstruct the banks would eventually be seeded in the treated areas. If successful, Border Patrol officials hoped to extend the imazapyr treatments to other sections of the river. The plan stirred fears that expanded use of the chemical could taint water supplies between Laredo and Brownsville and affect public health and the delicate ecology of the Rio Grande watershed. Although the Environmental Protection Agency had approved imazapyr as safe for people and animals, it has sparked controversy and legal action when used in other parts of the country. Last year, a California judge in Humboldt County responded to a lawsuit by environmentalists and stopped a plan to use imazapyr to eliminate weeds along the Eel River. He ordered an environmental impact report based on guidelines of the state's environmental quality law. According to a fact sheet issued by the Northwest Coalition for Alternatives to Pesticides, lab rats heavily exposed to large doses of imazapyr had increased incidence of various types of cancerous tumors. Concentrations of imazapyr have been detected in soil in areas where it was used by forestry companies for as long as a year after application. It is also potentially harmful to aquatic life, particularly frogs and amphibians. With legitimate questions about the long-term effects of the chemical unanswered, the decision to postpone its use on the Rio Grande is prudent and justified. It is curious that the Border Patrol cited complaints from Mexican rather than U.S. sources as the reason for suspending the pilot project. Laredo Mayor Raul Salinas, a former FBI agent, told the Chronicle's Schiller that the desire of authorities to secure the border needs to be balanced against a thorough examination of the project's consequences. Said the mayor, "Let's do it in a sensible, reasonable way to make sure humans won't be harmed, nor the vegetation, nor the animals, nor the environment." Just as security concerns have driven the multi-billion dollar construction of the border fence forward with inadequate consideration for its economic and environmental impact on border communities, so the plan to dump herbicide along the Rio Grande needs a lot more study and public comment before it is implemented. In the meantime, for $2 million, you'd think the government could find plenty of unemployed workers to cut a mile of cane growth without resorting to potentially polluting poisons.