Nov 11, 2024Field Day set to address Pacific flatheaded borer threat in walnuts
Walnut growers in Stanislaus County are invited to a field day organized by the University of California Cooperative Extension (UCCE) on Nov. 21 to tackle the increasing impact of the Pacific flatheaded borer on walnut orchards.
The event, hosted by UCCE Stanislaus County, will be held at the UC Cooperative Extension office in Modesto from 10 a.m. to 12 p.m. Experts will discuss integrated pest management (IPM) techniques, present findings on the pest’s biology and seasonal patterns, and offer hands-on demonstrations to help growers identify the borer and its damage in the field.
According to recent UCCE research, the Pacific flatheaded borer (Chrysobothris mali) has become a significant pest in walnut orchards over the last decade, especially in areas affected by environmental stress and high summer heat. The adult beetles lay eggs on walnut branches, and larvae feed on the cambium layer, leading to weakened, wilted branches and increased tree vulnerability.
PFB has been a serious pest throughout the U.S. and Southern Canada in the past, but is rarely seen in commercial orchards, according to Washington State University Extension. PFB attacks many trees and shrubs.
The borer attacks apple, pear, peach, apricot, plum, prune and cherry trees as well as many other trees and shrubs. Larvae kill or weaken trees by girdling the trunks and lower branches. Stressed plants are most vulnerable. Newly planted nursery stock, drought stressed trees, sunburned trees and trees whose trunks are exposed to the sun usually are the most seriously affected. One borer can kill or severely weaken a small tree, according to WSU.
The meeting is part of a five-year research initiative focused on developing practical strategies for managing this pest in walnut orchards. DPR and CCA credits are available for attendees.
Register to join the field meeting on Thursday, Nov. 21, 2024, for which 2-hour DPR and CCA credits have been approved.
