UC Research on Effects of Herbicide Milestone

Milestone, a herbicide from Dow AgroSciences, was registered about 9 years ago in California for mainly cattle ranged applications, targeting problem weeds.

Guy Kyser with the Department of Plant Sciences at UC Davis looked at how the herbicide was affecting good perennial grasses.

“Its used mostly for broadleaf weeds, its been a real help with the Yellow Starthistle. There was some concern about whether it might affect seedling grasses, especially the perennial native plants that we want to replant after controlling yellow star thistle, because it got a little bit of soil residual, which is good for thistles but we wanna make sure it wasn’t hurting our grasses, and that’s what this trial is. We treated several rates of Milestone, and replanted with several species of native California perennial grasses, to see if there was any impact on the seedlings.

Kyser found out that the important grass species are more tolerant to Milestone applied at the time of planting, then when milestone is applied to young seedlings. He noted that California Brome is the most tolerant grass to Milestone.

Kyser’s research was featured at the recent 58th annual UC Davis Weed Day.