The Spotted Lanternfly (SLF) is an invasive pest that poses a great threat to California's agriculture. It was first discovered in the U.S. in Pennsylvania in 2014 and has since taken the east coast by storm, causing damage to many plant species and proving to be difficult to control. Although this pest hasn't been found in California, it is important to keep an eye out to catch an invasion early.
What does the spotted lanternfly look like?
The SLF adult is about 1 inch in length with grayish wings, black spots, and red hind wings. Egg masses are laid in the fall on the east coast and resemble splotches of mud. They are often laid on smooth surfaces like branches, rocks, or outdoor furniture. Early nymphs are very small, wingless, and black with white spots. The last nymphal stage is 1/2 inch long and red with white and black markings.
What damage does the spotted lanternfly cause?
On the east coast, the spotted lanternfly's preferred host is the invasive tree-of-heaven (Ailanthus altissima), but it will also feed heavily on grapes, maples, willows, and birch trees. SLF feeds on plant sap and excretes honeydew, which can cause sooty mold to grow on leaves and fruit. It is known to kill black walnut saplings, tree-of-heaven, and grapevines. However, for most other plants SLF is considered a plant stressor and healthy plants can usually tolerate feeding.
What can you do to help keep the spotted lanternfly out?
Spotted lanternfly is easily transported to new areas as egg masses on firewood, stone, cars, and furniture. Check vehicles and trailers when traveling to areas where SLF has been confirmed. Inspect items purchased or shipped from these areas, and don't move firewood. Familiarize yourself with the various ways that SLF egg masses may appear and report any potential sightings to the CDFA Pest Hotline: 1-800-491-1899.
If you want to learn more, visit the UC IPM Spotted Lanternfly page and consider taking the California Master Gardener Spotted Lantern Fly training module.
There are several flatheaded boring beetles in California, however only a few are of particular concern. The goldspotted oak borer (GSOB), Agrilus auroguttatus, is a metallic wood-boring beetle that threatens our native trees. Since it was introduced to Southern California on contaminated firewood in the early 2000s, this pest has caused extensive damage to woodlands and native oaks.
What does the goldspotted oak borer look like?
Adult GSOB are 0.4 inch long and 0.08 inch wide with bullet-shaped bodies. They are black with an iridescent green sheen and six distinct gold spots on their back.
What damage does the goldspotted oak borer cause?
Goldspotted oak borers only attack oaks (Quercus spp.). They are particularly damaging to coast live oak and California black oak. Adult beetles lay eggs on host trees and the larvae bore into the wood, feeding on the tree's vascular tissue. The larvae feed on the tree until they pupate into adults and exit the tree, leaving D-shaped exit holes in the bark. Extensive GSOB feeding can girdle trees, disrupting water and nutrient uptake and eventually causing the tree to die.
What can you do about the goldspotted oak borer?
Don't move firewood! The most important way to prevent the spread of invasive wood borers like GSOB, is to buy firewood where you're going to burn it. If you live in an area of Southern California where GSOB is present, avoid planting susceptible trees. If you need to remove an infested tree, keep the cut wood away from healthy oaks and tarp or grind the wood to kill any larvae present. To report possible sightings, fill out the Goldspotted Oak Borer Symptoms Reporting Form at https://ucanr.edu/sites/gsobinfo/What_You_Can_Do/Report_GSOB_Symptoms/
To learn more about this invasive pest visit the UC IPM Pest Notes: Goldspotted Oak Borer or the UC ANR Goldspotted Oak Borer page.
- Editor: Jennifer Hopkins
Invasive Spotlight: Highway Iceplant
You've probably seen this invasive plant growing along highways or the coast in California. Highway iceplant, Carpobrotus edulis, was intentionally introduced to prevent soil erosion along highways and coasts but it has since invaded many different ecosystems and outcompetes native plant species. The California Invasive Plant Council (Cal-IPC) rated this plant as an A-1 species, meaning it is one of the “most invasive and damaging species that are widespread in the state.”
What does highway iceplant look like?
The highway iceplant, also known as the hottentot fig, is a succulent with fleshy three-sided stems. It grows as dense ground-covering mats and produces large yellow to light pink flowers in the late spring and early summer.
What can you do about highway iceplant?
For decades iceplant was widely promoted as an ornamental landscape plant. While its popularity has dwindled, it may still be available for sale in some nurseries. Avoid buying and planting iceplant. Instead, choose plants native to California and visit the PlantRight website to find similar-looking alternative plants. If you have iceplant on your property, it can easily be removed by hand pulling. Be sure to get all live shoots as it can regrow from any node left behind.
For more information, visit the UC IPM Pest Notes: Invasive Plants or the Cal-IPC Plant Report on the highway iceplant.
The Spotted Lanternfly (SLF) is an invasive pest that poses a great threat to California's agriculture. It was first discovered in the U.S. in Pennsylvania in 2014, and has since taken the east coast by storm, causing damage to many plant species and proving to be difficult to control. Although this pest hasn't been found in California, it is important to keep an eye out to catch an invasion early.
What does the spotted lanternfly look like?
The SLF adult is about 1 inch in length with grayish wings, black spots, and red hind wings. Egg masses are laid in the fall on the east coast and resemble splotches of mud. They are often laid on smooth surfaces like branches, rocks, or outdoor furniture. Early nymphs are very small, wingless, and black with white spots. The last nymphal stage is 1/2 inch long and red with white and black markings.
What damage does the spotted lanternfly cause?
On the east coast, the spotted lanternfly's preferred host is the invasive tree-of-heaven (Ailanthus altissima), but it will also feed heavily on grapes, maples, willows, and birch trees. SLF feeds on plant sap and excretes honeydew, which can cause sooty mold to grow on leaves and fruit. It is known to kill black walnut saplings, tree-of-heaven, and grapevines. However, for most other plants SLF is considered a plant stressor and healthy plants can usually tolerate feeding.
What can you do to help keep the spotted lanternfly out?
Spotted lanternfly is easily transported to new areas as egg masses on firewood, stone, cars, and furniture. Check vehicles and trailers when traveling to areas where SLF has been confirmed. Inspect items purchased or shipped from these areas, and don't move firewood. Familiarize yourself with the various ways that SLF egg masses may appear and report any potential sightings to the CDFA Pest Hotline: 1-800-491-1899.
If you want to learn more, visit the UC IPM Spotted Lanternfly page and consider taking the California Master Gardener Spotted Lantern Fly training module.
You've probably seen this invasive plant growing along highways or the coast in California. Highway iceplant, Carpobrotus edulis, was intentionally introduced to prevent soil erosion along highways and coasts but it has since invaded many different ecosystems and outcompetes native plant species. The California Invasive Plant Council (Cal-IPC) rated this plant as an A-1 species, meaning it is one of the “most invasive and damaging species that are widespread in the state.”
What does highway iceplant look like?
The highway iceplant, also known as the hottentot fig, is a succulent with fleshy three-sided stems. It grows as dense ground-covering mats and produces large yellow to light pink flowers in the late spring and early summer.
What can you do about highway iceplant?
For decades iceplant was widely promoted as an ornamental landscape plant. While its popularity has dwindled, it may still be available for sale in some nurseries. Avoid buying and planting iceplant. Instead, choose plants native to California and visit the PlantRight website to find similar-looking alternative plants. If you have iceplant on your property, it can easily be removed by hand pulling. Be sure to get all live shoots as it can regrow from any node left behind.
For more information, visit the UC IPM Pest Notes: Invasive Plants or the Cal-IPC Plant Report on the highway iceplant.
