Herbicide found after dozens of trees near Mountain View library decline

Laboratory testing has found varying levels of imazapyr, an herbicide ingredient, in soil and tree samples from areas where more than 30 trees declined near the Mountain View Public Library and Pioneer Park, city officials said.

The findings confirm that imazapyr was present in the affected areas and trees, but they do not show how much the herbicide contributed to the trees’ decline or whether other factors also played a role, according to Mountain View officials.