San Diego County tree care and landscape professionals and land managers have a great opportunity coming up to learn about the latest research in the ecology and management of oak pests Feb. 6th at the Balboa Park Recital Hall. UCCE has teamed up with City of San Diego Parks and Recreation, County of San Diego Ag. Commissioner, and the US Forest Service to host a workshop to provide information about oaks and oak woodlands at risk, pests and diseases threatening oaks, pesticide use and firewood management, and a new reporting program. They will specifically address the Gold Spotted Oak Borer and the Polyphagous Shot Hole Borer.
- Author: Jan Gonzales
- Author: Sabrina L. Drill
The goldspotted oak borer (GSOB) - an invasive, non-native wood borer that has already attacked and killed tens of thousands native oak trees in San Diego and Riverside Counties - continues to be a threat for the southern California region. The information provided during this training will be helpful to land managers, arborists, property owners, volunteers and others who are concerned about the stewardship of oaks and oak woodlands. Our goal is to inform as many people as we can about the threat and impact of GSOB, symptoms of a GSOB attack, how to diagnose a declining tree and what to do to limit further infestation.
Includes hands-on examples, handouts, and refreshments.
This is a FREE training event. Continuing Education Units have been requested.
Questions? Contact Jan Gonzales, firstname.lastname@example.org/span>
- Author: Jeannette E. Warnert
When actress René Russo appeared in a video about “New Oak Threats,” she wasn’t acting. The veteran of big-budget thrillers like Lethal Weapon 3 and 4 and the Thomas Crown Affair expressed her personal convictions when she called for Californians to become educated and observant guardians of California oaks.
“I love our beautiful oak trees,” Russo said. “But there’s a new pest in town, and we could potentially lose every tree that we have. It would change the face of Southern California. It’s terrifying.”
The actress says the death of 80,000 oak trees in San Diego County since 2008 from goldspotted oak borer is one example of the devastation wreaked by one invasive pest.
“We need your help to save the trees,” Russo said.
Goldspotted oak borer, a native of southeastern Arizona, feed beneath the bark of certain oak trees. After several years, the damage to nutrient- and water-conducting tissue kills the tree.
Polyphagous shot hole borer carries a fungus from tree to tree when it burrows in bark to lay eggs. The fungus grows and spreads throughout susceptible trees. Some trees suffer branch die-back, while others are killed outright. The polyphagous shot hole borer is not only a threat to oaks but it can also affect more than 200 other tree species, including native California sycamore, avocado, and many popular street tree species.
“It’s really a whole landscape changer,” said certified arborist Rosi Dagit of the Resource Conservation District of the Santa Monica Mountains. “All of our street trees, our urban landscape trees and all of our wildland trees are at risk. What we really need are eyes on the ground.”
In the second half of the video, Sabrina Drill, UC Cooperative Extension advisor in Los Angeles County, explains what Southern Californians can do to protect trees.
- Visit the website Southern California Oak Pests (http://ucanr.edu/socaloakpests) to learn about the pests.
- Educate your friends, neighbors and community leaders about the pests.
- Don’t move firewood in and out of your local area. If you buy firewood, ask where it came from. On camping trips, burn wood you collect or purchase and don’t take any home. For more on firewood see the website Dontmovefirewood.org.
- Learn what to look for and report your observations on the Southern California oak pests website.
- Be an advocate for your trees.
“Hopefully, we can get this done,” Russo said. “We’ve lived with these beautiful oak trees for thousands of years. It would be devastating to lose them.”
The video, a joint effort of UC Cooperative Extension and the Resource Conservation District of the Santa Monica Mountains, was produced, directed and edited by Toby Keeler of Fine Cut Inc.
- Author: Sabrina L. Drill
There's been some recent news coverage about new threats to our oaks. Gold Spotted Oak Borer was recently found in Riverside County in Idylwild, and Rosi Dagit from the RCD of the Santa Monica Mountains wrote about GSOB and the Poylphagous Shot Hole Borer in the Topanga Messenger. "Imagine what Topanga and the Santa Monica Mountains would look like if all the oaks were gone. While we have long focused on development as a major threat to our oaks, there are some new threats, possibly as close as your woodpile that could be even more devastating to our trees" she writes. You can read it here.
- Author: Sabrina L. Drill
A new study published in the Journal of Economic Entomology reports that 50% of the wood showed signs of insect infestation, and live insects were found in 47% of firewood bundles purchased from big box stores, gas stations and grocery stores in Colorado, New Mexico, Utah and Wyoming.
Untreated firewood can harbor pathogens and destructive insects such as the gold spotted oak borer, the Polyphagous shot hole borer, the emerald ash borer, and other boring and bark beetles and transport them to uninfested areas. Furthermore, the risk of moving insects in untreated firewood is high, the authors found, because insects continued to emerge over 500 days from the date of purchase.
There are currently no national regulations on the commercial firewood industry that require firewood to be treated before use or sale to reduce the transport of live insects or pathogens on or in the wood. Several state and federal agencies are attempting restrict the transport of firewood for sale to reduce the risk of introducing invasive pests The authors concluded that heat-treating firewood so that insects or pathogens are killed prior to shipping would be prudent. This would not restrict firewood commerce as much as bans on firewood movement across state borders.
For more information, visit http://www.dontmovefirewood.org/