In California, P. ramorum is primarily a leaf pathogen and thrives in coastal tanoak/redwood forests and oak woodlands. There are two categories of hosts for P. ramorum....
As you practice social distancing during COVID-19, you may find yourself spending more time in the garden. As we move into nice weather, we are sharing a few gardening tips for pest management.
Powdery Mildew
Check for signs of powdery mildew on fruit trees, landscape ornamentals, and vegetables. Symptoms can vary by plant species but common symptoms include white powdery spots developing on both sides of the leaf, leaves that turn yellow or brown and fall off, twisting and distortion of leaves and shoot. Prune out small infestations and remove infected material to reduce spread.
For more on this...
/h2>Roses in the garden can be infected with a variety of bacteria, fungi, and viruses, leading to diseases like powdery mildew and rust. Roses may also be damaged by nutrient deficiencies and other environmental problems.
Our Pest Notes: Roses: Diseases and Disorders was recently updated by University of California experts John Karlik, Deborah Golino, and Maher Al Rwahnih. This free publication provides an integrated approach to managing rose problems that includes careful variety choice, proper irrigation, correct pruning, and sanitation. Although some rose enthusiasts might consider regular application of fungicides a necessary...
What is Armillaria Root Rot?
Armillaria root rot is a severe fungal disease that affects trees, woody plants, and some herbaceous plants including palms and succulents.
Also known as oak root fungus, Armillaria root rot can rapidly kill trees and presents a challenge to management since infected woody roots can persist for years underground. No plants are completely immune to Armillaria root rot, so prevention is key. Deeply planted trees are often more susceptible to this disease.
The distinctive “honey mushrooms” growing from the base of a tree signals an infection, but they may not always be present. Other visible symptoms include flat cankers on the trunk, wilting, and canopy...
/h2>The California Department of Food and Agriculture has declared a quarantine following the detection of Huanglongbing (HLB) in multiple residential citrus trees in Corona (Riverside County). This is the first time HLB has been detected in Corona.
The 107-square mile quarantine area will link up with the east side of the existing quarantine in Los Angeles, Riverside, Orange and San Bernardino counties, creating a contiguous 1,127-square-mile area. The new portion is bordered on the north by Chino Airport, on the south by Black Star Canyon, and on the east by Interstate 15.
The quarantine prohibits the movement of all citrus nursery stock or...