- Author: Dustin Blakey
Recently brown marmorated stink bugs (Haylomorpha halys) were found in Inyo and Mono counties. This invasive pest from Asia is relatively new to our area. Its first sighting was in Bishop last year.
We have plenty of species of stink bugs on the east side, but this one is especially annoying because it tends to aggregate in large numbers and will attempt to get inside homes and structure to avoid cold weather. As our temperatures return to more normal ranges, I would expect more issues with home ingress.
We have had reports from Swall Meadows down to Big Pine, and possibly an isolated case in Olancha. My hunch is they arrived from northern California, not down south, but there is no way to tell for sure.
As of now, most stink bugs you will encounter are not BMSB. You can identify this pest by a couple notable features: like many stink bugs it is brown, but it has white bands on its antennae and has alternating white and dark coloration on its abdomen. It also has rounded shoulders; similar species in our area have pointed shoulders.
Spraying adult stink bugs doesn't do much good. The best course of action is to ensure your homes are sealed up well so they can't get in.
If these bugs do come inside, they can be trapped easily. (Squishing them is just messy and smelly. Trapping is a better choice.) Here is a video from Virginia Tech showing a good way to trap them.
Stink bug trap - Virginia Tech from VirginiaTech on Vimeo.
They can also be vacuumed up. Here is what UC IPM suggests you do:
An efficient way to collect stink bugs indoors is by sucking them up with a dry or wet vacuum. The bugs will cause the collection canister or bag and other parts of the vacuum to give off an unpleasant stink bug odor, so some people dedicate a vacuum cleaner to stink bug capture only. Alternatively, a nylon stocking can be stuffed inside the tube and securing the end over the outside of the vacuum tube with a rubber band; this way, bugs are collected in the stocking and not the vacuum cleaner bag. Individual stink bugs can be brushed off into a cut-off plastic bottle containing an inch of soapy water, where they will drown in a short period of time. If needed, the container can be fastened to a pole or broom handle to reach high locations. Stink bugs caught live also can be placed inside a plastic sealable bag and then into a freezer for 2 days to kill them. To conserve water, avoid flushing them down the toilet and avoid placing live stink bugs in the garbage so they do not become established around landfills.
Hopefully this will just be a minor nuisance for us, and nothing more.
For more information consult this page at UC IPM or send a message to our helpline at immg@ucanr.edu.
- Author: Trina Tobey
They plague every gardener's nightmares. Like something from a sci-fi movie, they are green with long legs and antennae and long piercing mouths with which they suck out fluids. They eat 100 times their body weight, and—worst of all—they multiply asexually by the dozens in a day!
My first experience with aphids as a beginning gardener was watching the leaves on my plum tree wilt. The flowers fell off and died instead of producing fruit. This prompted me to research what I could do to protect my fruit trees. Here is what I learned.
In fall it is time to start your preventative measures for aphids on fruit trees for next year. After harvest, a zinc sulfate application on plums and prunes will provide zinc to the trees as well as hasten leaf fall disrupting the aphid life cycle.
If aphids are a chronic problem in your fruit trees, you can apply supreme- or superior-type oils to kill overwintering pests during dormancy this winter. This helps to start the following season with a clean slate.
In the spring, start monitoring your trees for aphids as soon as leaves begin to bud. Check for aphids on the underside of the leaves on several areas of your trees at least twice weekly. Ants tend aphids and collect their honeydew and large numbers of ants climbing up your tree trunk is an indicator that you may have aphids. Over watering and over fertilizing can increase aphid populations so only apply the minimum necessary for healthy plant growth.
One excellent way to reduce aphid populations is to knock them off with a strong spray of water.
Several natural predators feed on aphids including lady beetles, green lacewings, brown lacewings, syrphid flies, and soldier beetles. Predators can be released onto the trees but often appear naturally in significant numbers when there is a significant aphid population. Where aphid populations are localized on a few curled leaves or new shoots, consider pruning these areas out. Drop the infested plant parts in a bucket of soapy water. If insecticide sprays are needed, insecticidal soaps or horticultural oils are generally the best choice. Avoid using broad-spectrum insecticides which will kill natural predators and consequentially could increase your aphid population.
In our area, it can help to keep weeds under control near your trees.
With these tips, you can save your home orchard from an aphid invasion like the Men in Black saved earth from an alien invasion and go back to sleeping soundly throughout the night. Good luck!
References:
Agriculture and Natural Resources, University of California (2019). Leaf Curl Plum Aphid. Retrieved from http://ipm.ucanr.edu/PMG/r606301811.html
Flint, Mary Louise (2018). Pests of the Garden and Small Farm: A Grower's Guide to Using Less Pesticide, Third Edition. Oakland, CA: The Regents of the University of California Agriculture and Natural Resources.
- Author: Dustin Blakey
If you have cats (and you like them) chances are you've tried giving them a sniff of catnip to see what happens. Of my last two cats, only one seemed to notice. Many cats don't respond at all to catnip's fragrance. But that's probably fine with the catnip plant (Nepeta cataria). You see, cats probably aren't the plant's target.
In this video, you'll learn a bit about how catnip works and what scientists think its active ingredient (nepetalactone) is for and its relationship with common garden pest. Even if you're not all that interested in catnip, the video features lots of clips of cats. Isn't that why we have the Internet?
- Author: Dustin Blakey
This is the time of year that folks get concerned about defoliation of their elm trees. Usually the culprit is a small yellow beetle called, appropriately enough, the Elm Leaf Beetle. It eats elm leaves.
The adults cause small shot holes in the leaves, but the larvae will turn a leaf into skeletons. That's what we're seeing now in late July and early August. The larvae have big appetites!
This is the second generation of the pest this year. The first happened in June. Soon the larvae will crawl down the tree to pupate and repeat the cycle once again. Aberdeen and points south will probably have 3 generations this year. Bishop and Big Pine may also have 3 if the weather stays warm and we have a long autumn, but usually have 2 generations since the growing season is shorter.
There isn't much point in spraying the tree canopy now or using systemic insecticides this late in the season. If you notice the larvae crawling down the tree, it is probably worthwhile to do a band spray on the trunk with an approved insecticide. This is about when that happens on average in Independence and Lone Pine. Big Pine and Bishop are a week or two behind. Since the heat started early, we may be sooner than average this year. The only way to know is to inspect your trees often. Temperature drives development of this pest.
If you notice an accumulation of pupae at the base of the tree, vacuum or sweep them up right away.
Largely this is a pest of humans more than elms if your trees are otherwise healthy. They aren't doing the tree any good, but most of the problem is the mess and lack of foliage in landscapes. Keep that in mind if you decide to treat. There are dozens of elms in Owens Valley that get these every year and never get treated, yet are still alive and well.
You can find a lot more information about these insects on the Elm Leaf Beetle page at the UC IPM program website. It includes information that can help you to decide whether to attempt control of them.
David Haviland, Entomology Advisor, UCCE Kern County
Over the past few weeks there have been numerous reports of bug invasions near Ridgecrest, Inyokern, and other cities in the high desert of eastern Kern County. Residents and business owners have reported large aggregations of bugs within their homes, businesses, and on the streets. There have been no reports of damage to agricultural crops, landscape plants, or people. However, the nuisance and paranoia associated with bugs crawling on business walls and people has led to numerous inquiries into what is going on and how long it will last.
The bugs belong to a family of insects called lygaeids that are commonly referred to as seed bugs. Seed bugs use their straw-like mouthparts to extract moisture and nutrients from a wide range of plants, especially ones with seeds. The specific species of insects being found in Ridgecrest and surrounding areas is called Melacoryphus lateralis. It does not have a common name. This bug is very similar in appearance to other insects in the families Lygaeidae and Rhopalidae, such as the boxelder bug and milkweed bugs. It is not a beetle.
M. lateralis is found throughout the western United States and is most common in desert areas of Arizona, Nevada, Texas, and southern California. Immature and adult insects feed on native desert plants and then fly to find new feeding sites or mates when they are adults. Adults are highly attracted to lights and can fly long distances, especially in search of succulent plants on which to feed as desert plants become dry during mid-summer.
Populations of this insect vary from year to year with outbreaks most commonly reported in the Sonoran Desert areas of Arizona in years with elevated monsoon-like weather associated with above-average rainfall. In the areas around Ridgecrest, above-normal populations of this pest in 2015 are likely the result of a mild winter followed by above-normal rainfall in February that provided ample food for nymphs throughout the desert. Then, in July and August, the combination of drying host plants and the attractiveness of lights has caused mass migrations of the bugs to urban homes and landscapes.
Management of the bugs is difficult due to the migratory nature of adults. Pesticides that kill insects on contact, such as home perimeter treatments used by licensed pest control companies, can provide excellent control of bugs that they come in contact with, but are unlikely to have any residual effects after one or two days. Businesses and homeowners are encouraged to keep doors closed and turn off lights whenever possible after dusk to reduce the risk of attracting bugs. Once bugs get inside structures, vacuuming is the preferred method for their removal. Outdoors the bugs can be swept with a broom or blown away from business entrances, porches, or parking lots with a leafblower.
Nobody is certain how long the insects will be around. However, reports from Arizona suggest that aggregations of adults occur in July and August, which suggests that populations are likely to become reduced over the next few weeks. These reports also suggest that the outbreaks that are occurring in 2015 are likely a one-time anomaly that won't repeat itself again unless the favorable environmental conditions for the bugs are repeated. For the sake of Ridgecrest residents, let's hope that doesn't occur.