UC Weed Science

While most Californians are staying home to slow the spread of the novel coronavirus, California farmers, farmworkers and other agricultural professionals are out in the fields and packing houses working to produce food.

Last summer, I was called out to view what appeared to be a herbicide drift incidence in a commercial tomato field. The leaves of affected plants were distorted with cupping and twisting that is characteristic of the growth regulator herbicides such as 2,4-D and dicamba (Figure 1).

Here are training videos on Weed Control Techniques. You may see a few familiar faces.

How to Control Mustard with Grazing Summer mustard, sometimes also called short-pod mustard (Hirschfeldia incana) and black mustard (Brassica nigra) are common rangeland weeds on California's Central Coast. Summer mustard seems to be the more common species.

Stinkwort (Dittrichia graveolens) is a very sticky annual weed in the sunflower family with a powerful smell similar to tarweeds (Brownsey et al. 2013). Its first observation in California was in Santa Clara County in 1984.