Paranoia, helicopters, herbicides


March 25th: An association of Hispanic residents from two Texas barrios near the Rio Grande river file a lawsuit complaining that the Department of Homeland Security has acted "arbitrarily and capriciously" in violation of the National Environmental Policy Act. The group, called Barrio de Colores, hopes to stop the Border Patrol from going forward with their plan  to apply the herbicide Imazapyr to the Carrizo cane lining the river. 

Carrizo cane (Arundo donax) grows in thick, claustrophobic stands along the Rio Grande. The forests can grow up to 30 feet high, and are scored by a maze of footpaths. One of the fastest growing plants on land, Carrizo cane has been used since ancient Egypt to make flutes and paper, and is still used by people in Mexico for baskets and pinatas.

Photo courtesy of U.S.
Department of Homeland

None of these qualities endear it to the Texas Border Patrol. To them, the cane just provides excellent cover for illegal immigrants and criminals, and they're on a mission to eradicate it.

At first glance, comparisons of the Border Patrol plan to the application of Agent Orange in Vietnam seem hystrionic. It's easy to understand why people don't want a chemical contained in products with names like "Arsenal," "Stalker," and "Assault" drifting over their homes, but the EPA characterizes Imazapyr as a low risk to human or animal health. Tom Dudley, an expert in tamarisk control who currently works at UCSB, says that, although he's "one of the most anti-chemical people around...not all chemicals are the same." He considers Imazapyr "pretty non-toxic."

However,  disagreement about how dangerous the chemical really is, environmental concerns, and the Border Patrol's failure to invite public participation in their environmental assessment have sparked a battle between the Mexican government, the Texas Border Patrol, and communities who live along the river. Ground zero is Laredo, Texas, where the first test application of Imazapyr is scheduled to start today, unless Barrio de Colores can stop it.  

Barrio de Colores charges that the Border Patrol has not been forthright about the potential for drift of the chemical from helicopter spray.  Forty percent of an herbicide leaves the "target area," according to their report, traveling as far as two or more miles from the treatment site. Since there are playgrounds, schools and homes nearby, they are concerned about their children. 

Known effects of exposure to Imazapyr are skin and eye irritation; the citizens of Laredo and Nuevo Laredo across the river are worried about potential unknown health risks. When residents of Nuevo Laredo were advised to shut down their water intake for 48 hours during application, suspicions about the supposedly harmless chemical went through the roof.

Imazapyr disrupts the synthesis of amino acids in plants. It's a highly effective, mobile, persistent chemical  herbicide that can take more than a year to break down in soil, although in water it takes about two days. Tom Dudley  says he's a little puzzled why the Border Patrol would use Imazapyr rather than glyphosphate, which breaks down much more quickly. It's a good thing to get rid of the cane, he says-- it's lousy habitat for birds, and aquatic insects don't find it habitable. To promote more biodiversity, the cane should go. However, his concern is that the widespread elimination of vegetation along the river bank could cause massive erosion. The Border Patrol says they have plans to stabilize the soil and replant with native vegetation, but considering the chemical's persistence, this could take a while. 

Barrio de Colores agrees that the cane is problematic, but wants the Texas Border Patrol to consider alternatives to the helicopter spraying, such as clearing the cane manually as they do across the river in Nuevo Laredo.  This could provide green jobs and a source of biofuels. Jay J. Johnson Castro, Sr. of the Rio Grande International Studies Center, says the group is not even opposed to using Imazapyr if truly necessary, but it needs to be applied in a more controlled, judicious way. 

The Laredo City Council voted 5-3 to allow the Border Patrol to go ahead with its plan on March 16th. The public relations officer said that permission was granted only after pointed questioning and reassurances that the Border Patrol would comply with guidelines from the Fish and Wildlife Service in its application, such as not spraying when there are tailwinds of five miles per hour or more. "There is no safe chemical," said the Council spokesperson, but "with proper precautions we can mitigate the consequences." One of those votes was a mistake, says Castro. The council member pushed the wrong button and is calling for a re-vote. 

The Mexican government opposes the Imazapyr plan, which raises questions about whether the Border Patrol is violating international environmental law. Barrio de Colores has retained top environmental lawyer Dinah Bear, who has served in the General Counsel of the Council on Environmental Quality, to make their case.