Invasive plants—plants that can disperse, establish, and spread without human assistance or disturbance—pose a serious problem in California's waterways, wildlands and rangelands. Common garden weeds, unlike invasive plants, don't generally thrive outside of cultivation.
About 1,500 non-native plant species are currently established in California, mostly in wildlands. Almost two thirds were intentionally introduced as ornamentals from the nursery industry, or for the purposes of soil stabilization, animal forage, human food, fiber or medicinal plants.
Invasive plants originally introduced as desirable ornamentals include pampasgrass, big periwinkle, and water hyacinth. Dyer's woad was once a valuable dye...
- Author: Belinda Jane Messenger-Sikes
[From the August 2016 issue of the UC IPM Green Bulletin]
A new psyllid pest that causes a distinctive, tight, typically complete rolling of leaves (Figure 1), has been found on Ficus microcarpa (Chinese banyan, Indian laurel fig) in Los Angeles, Orange, San Bernardino, Ventura, San Diego, and Riverside counties. This species of Ficus is one of our most common, useful, and widespread ornamental landscape trees. Incidentally, it has also long been a target for numerous exotic pests.
The psyllid, identified as Trioza.../span>
[From the March 2016 issue of UC IPM's Retail Nursery & Garden Center IPM News]
Asian citrus psyllid (ACP) continues to spread and to be an ever-present concern in California. Because of this, we have updated information from the April 2015 issue of UC IPM's Retail IPM newsletter to share with your customers.
Until 2013, ACP was mostly found in Southern California, but has since been found in multiple locations in the Central Valley and has been detected as far north as the San Francisco Bay Area. The psyllid is well-established in coastal and inland Southern California and it is slowly establishing itself in...
- Author: Jeannette E. Warnert
Weeds are easiest to control when they are tiny emerging plants, reported Jeanette Marantos in a Los Angeles Times blog post. Marantos got tips on weed management from Cheryl Wilen, UC Cooperative Extension integrated pest management advisor in Southern California.
Wilen recommends home gardeners use a swivel (or hula) hoe to scrape the surface and decapitate weeds. “It's a bit of exercise,” she said, "but you can do it so quickly, it's not a problem.”
Another weed control strategy is a thick layer of mulch, with does double-duty by...