Residents who live close to and use Highway 84 in rural San Mateo County say Caltrans has not only gone back on its promises not to broadcast-spray herbicides to kill weeds along the state highway this year, but that the state agency also may have violated federal law by unsafely applying herbicides.

A resident of Half Moon Bay who works in La Honda, who has asked that her name not be used because she fears retaliation, told the Almanac that on Wednesday, March 2, in mid-afternoon she saw a crew that included at least 10 workers, with only a few of them wearing protective gear, spraying near where Old La Honda Road meets Highway 84, across the highway from the iconic red barn.

Photos taken 10 days later clearly show large swaths of vegetation killed by the chemicals, despite the fact that Caltrans had sent out notices saying it would not broadcast-spray herbicides along Highway 84 this year. Residents say the dead vegetation covers at least a quarter-mile of roadside.

Caltrans spokeswoman Gidget Navarro said in February that Caltrans would do "spot spraying soon but no broadcast spraying." She said that spot spraying is done on isolated small areas, or at the base of plants that have been removed, to prevent re-sprouting.

The labels for the chemicals Caltrans had said it planned to use in the area, Capstone and Accord, both state that only workers in protective gear should be in the area when the chemicals are applied. "Only protected handlers may be in the area during application," the Accord label states.

"Do not enter or allow others to enter the treated area until sprays have dried," the Capstone label says.

The labels also both say: "It is a violation of federal law to use this product in a manner inconsistent with its labeling."

The witness said she saw workers with California Conservation Corps logos on their uniforms and vehicles; they were cutting and removing weeds by hand. With them, as part of the same crew, were people "in white protective gear ... with their spray stuff."

"I realized the conservation corps people had no protection," she said. Other workers were nearby chipping debris and directing traffic, which was reduced to one lane, she said.

The Capstone label also has a number of cautions about using it when it could contaminate water supplies, yet the weather prediction on March 2 was for rain within the next 48 hours, and by the end of the day of March 4, it had rained 0.6 inches in La Honda.

Photos taken on March 12 by local residents clearly show dying vegetation along ditches flowing with water.

The Capstone label says: "Do not contaminate water intended for irrigation or domestic purposes. Do not treat inside banks or bottoms of irrigation ditches, either dry or containing water, or other channels that carry water that may be used for irrigation or domestic purposes."

When contacted last week Caltrans officials said they were busy working on other projects and couldn't do anything until Monday, which is after the Almanac's deadline.