Pest Management & Plant Health

Toxic baits, or rodenticides, used to control rodents around the home and garden can harm nontarget animals, such as pets, birds, coyotes, and other wildlife. To reduce these negative impacts, California has passed several laws to limit what rodenticides can be used, how, and by who. Here’s what you need to…

Mosquito season is in full swing in California, and the deadly West Nile virus is making its way around the state. Health officials have identified the virus in 17 counties and there has been 1 confirmed human death so far this year. West Nile virus is one of several diseases that can be transmitted to…

Dogs use their keen sense of smell to help humans every day. Their powerful noses alert us to danger, aid in search and rescue operations, and even have the potential to diagnose diseases. But did you know that some dogs have been trained to sniff out potential invasive pests? Enter—the detector dogs! …

A virus can reduce a plant’s growth, lower its yield, and result in inferior fruit, vegetables and flowers. Viruses are often very host specific. Recognizing symptoms can help you take appropriate action, where possible, to manage a virus and hopefully prevent its spread. The following are several viruses…

The dotted paropsine leaf beetle (Paropsis atomaria), an invasive pest native to Australia, was first discovered in California in 2022 and is rapidly spreading throughout Southern California targeting eucalyptus trees. Both adult beetles and their larvae feed on eucalyptus leaves, causing significant…

Most gardeners are aware of plant diseases that can wreak havoc in their gardens. If you grow fruit trees, you may be confronted with curled, reddened peach leaves (peach leaf curl fungus). If you grow apples or pears, your trees may sometimes look like they were scorched with a blow torch (fire blight…

You have probably heard about the “good bugs” that eat pest insects around your home and garden, like ladybugs, lacewings, and spiders. You may have even purchased some beneficial insects or nematodes at a garden store. Good bugs can also help us manage invasive species, but the process is a bit more…

Tumbleweeds rolling across the landscape may make you think of classic old Western movies, but tumbleweeds, or Russian thistle, is more common today than you might think. This invasive plant can grow anywhere the soil is disturbed and once it matures, it breaks off its stem and the dried plant blows across…

The black stuff on your leaves is likely sooty moldThe black stuff on your leaves is probably sooty mold, a fungal disease growing on plants and other surfaces, and it is often seen in the spring and summer. The leaves or stems have a black coating that looks like soot. If you look closely, it is growing…