UC Weed Science (weed control, management, ecology, and minutia)

Its that time of year again when hot weather fuels the creation of ozone, or smog. Some herbicides emit volatile organic compounds (VOCs) that contribute to ozone formation. Using herbicides that release VOCs may be restricted in certain California locations between May 1 and October 31.

Threespike goosegrass is a warm season perennial grass which is a problem weed in some almond orchards around Orland, California. It is easily identified by its distinctive (see photo) seed heads (spikes). It is usually a problem during the first years of an orchard.

June 17, 2013 CONTACT: Jeannette Warnert, (559) 240-9850, jwarnert@ucanr.

According to a previous ANR blog post, the 2013 processing tomato crop in California is experiencing worse-than-usual curly top problems, which is caused by a complex of Beet Curly Top Viruses (BCTVs) (Processing tomatoes face critical threat: curly top).

Poison hemlock, Conium maculatum, was brought from Europe into the U.S. as an ornamental in the 1880s and now occurs throughout North America. In California it is most commonly found at lower elevations and coastal regions but it is continuing to spread into other areas.