- Author: Anne E Schellman
Are you fascinated by insects? Do you want to learn more about them but aren't sure how? The Stanislaus County UCCE Master Gardeners are offering a chance to help you get started. Instructor Anne Schellman will present on how to classify and identify insects and the process for collecting and pinning. You'll also watch a hands-on demonstration on how to pin and “style” your insect to look its best in your collection, followed by trying it out yourself!
This class is designed for adults (18 and over) interested in starting their own collection. Join us on Tuesday, May 14, at the San Joaquin Agricultural Center in Stockton from 9:30 a.m. to 12:00 p.m. The cost is $40 and includes a glass-topped collection box, pins, preservation strip, and educational materials. We will also provide a light breakfast of fruit, granola bars, tea, and coffee.
If you want to attend up, please sign up ASAP! The class is limited to 30 people and there are only 14 spaces left. Visit http://ucanr.edu/bugs2019
Payment online is by credit card only. If you would prefer to pay cash or check, contact Anne Schellman at (209) 525-6862 or aschellman@ucanr.edu. We will need your payment by Friday, May 10.
- Author: Dustin Blakey
I drove down to Ridgecrest last week hoping to check out the wildflowers. While I did eventually get to see some great blooms, I had to stop a couple times to clear off my windshield which looked something like this:
In March the annual northern migration of painted lady butterflies (Vanessa cardui) had arrived in southern California, eventually arriving in our area. No doubt you have seen those that didn't collide with my windshield in great numbers on fruit tree blossoms and and other blooms.
This is a annual event, but according to Dr. Art Shapiro their numbers are huge on years that have large wildflower blooms. The last major large migration was in 2005.
The Eastern Sierra is a favored path for their travels to the Pacific Northwest. It will take several generations of the butterflies to make it northward, and then the process will repeat in the autumn when they return to Texas and Mexico for the winter.
NBC News down south did a piece on these butterflies. You can see it here.
I always find these mass migrations of insects interesting. I am glad that in this case it's something harmless and beautiful.
However, where they decide to nest can quickly turn them from friend to foe!
I was recently weeding a planting bed near our barbecue when I was stung in the abdomen and chest by a couple of aggressive little wasps. Our outdoor fire pit and dining area are in the same general area and we, and our dog, hang out there all the time. The wasps were flying around a stacked-rock retaining wall, so I sprayed some hornet and wasp spray into the crevices and figured I had solved the problem.
But a week later when I saw several wasps flying around the same area, I was surprised to see them emerging from the ground behind the wall. I decided I needed some help with the situation and immediately called Deb Conwayn with GirlzWurk in Saratoga. Deb is a beekeeper, does bee removal and relocation, and sells amazing honey. I was lucky to reach her right away and she came to our house the same day.
When we removed a large section of the stacked wall and dug a few feet into the soil, we found a huge, eight-layer yellowjacket nest. Deb guessed that there were at least 5,000 live yellowjackets in there! She smoked and removed the hive and vacuumed up the wasps. Apparently, they had created their nest in an abandoned gopher hole.
These yellowjackets were smaller and darker than most that I had seen so I sent the photos off to UC Davis for identification. Per Lynn Kimsey, director of the Bohart Museum of Entomology and professor of entomology at Davis, mine was a Vespula vulgaris, or common wasp. “It's the second most abundant yellowjacket in California after Pensylvanica, the so-called western yellowjacket.” said Kimsey.
Vesplua is a small genus of social wasps. They, along with their sister genus, Dolichovespula, are known as yellowjackets or yellow jackets. Vespula vulgaris have a stronger tendency to nest in the ground than other species.
Their normal habitat is dry grasslands and woodlands, however, they have certainly adapted to our urban areas. Only the queens survive the winter. They emerge in the spring to build their paper-like nests (made from chewed wood pulp) in hidden cavities like animal burrows, tree stumps, or in crevices like rock walls.
The initial brood of larva, which is cared for by the queen, hatch into workers who continue to build and protect the nest. They also care for the subsequent broods. Workers only live about two to four weeks and are replaced throughout the summer.
Again, all wasps can be beneficial and definitely serve a purpose. But, if you or a family member are allergic to their venom or they have taken up residence in a place that is intolerable, you may want to take action to relocate or eradicate them.
Deb Conway services most of the South Bay and can be reached at 408-373-0454. Find other good bee removal services at BeeRemovalSource.
by UC Master Gardener Rebecca Jepsen
This article first appeared in the October 28, 2018 print issue of the San Jose Mercury News.
The tarantula hawk (Pepsis formosa) is actually a spider wasp that can grow up to 2 1/2 inches long with a 4-inch-wide wingspan. This one had a beautiful blackish-blue, metallic body with vivid, bright orange wings. Some have shiny blue/black wings that match its body. It has long black antennae and six velvety black legs with hook-like claws on the ends.
As the name indicates, they prey on tarantulas, which they need as hosts for their larvae. (I have only seen one tarantula on my property in the six plus years we have lived here).
Only the females sting. She will fly low to the ground looking for spiders. When she finds a tarantula's burrow she will disturb the web, mimicking trapped-prey. When the tarantula emerges to inspect its web, she will sting and paralyze it. She will then drag the tarantula back into its burrow, lay a single egg on its body and then cover over the opening to the burrow.
When the egg hatches, the larva will feed on the still-living spider, avoiding the vital organs in order to keep the host alive as long as possible. After approximately three weeks to a month, the larva will emerge from the now-dead tarantula's body.
Adult tarantula hawks feed on pollen and nectar from flowers, and juice from fruits and berries. They seem to be especially attracted to milkweed, soapberry trees, and mesquite trees. Males live approximately two months or less; females can live longer.
Although the tarantula wasp is not aggressive and stings are relatively rare, it is reportedly one of the most painful stings of any insect in the world. The stinger is a fierce 1/3 of an inch long. The pain is said to be absolutely excruciating and so debilitating that you can lose control of your body. If you get stung, it is recommended that you lay down as quickly as possible to avoid stumbling and falling and causing further injury. An intense, burning pain will last for about 5 minutes. You may experience swelling and soreness around the area for a few days – but it will pass and is not life-threatening.
Fun facts:
- Species of tarantula hawks have been seen as far north as Utah and as far south as Argentina, with more than 250 species living in South America.
- Fifteen species of Pepsis are found in the United States, most of them residing in the desert.
- They are generally active during the summer months. They avoid the hottest part of the day (mine was out in early evening).
- Due to their extremely large stingers, they have very few predators; only roadrunners and bullfrogs will take them on.
- The tarantula hawk is the state insect of New Mexico.
So, definitely admire this wasp from afar, but avoid contact, and make sure your kids and pets do as well!
by UC Master Gardener Rebecca Jepsen
This article first appeared in the August 26, 2018 print issue of the San Jose Mercury News.
- Author: Alison Collin
Two years ago, overwhelmed by carpets of wormy, windfall apples I resorted to tossing them into a large plastic stock tank that had numerous holes in its sides, remnants of its original purpose - a crawdad washing device.
However, after a couple of weeks I needed the container and on tipping it over was astounded (and a bit revolted) to find that the bottom contained layers of hundreds of larvae. They were dark, grayish brown. I had not been aware of pest flies in the area, and there was no odor, but the huge numbers of larvae present gave me cause for concern. Research showed that I had just made my acquaintance with Black Soldier Fly larvae, Hermetia illucens, a species that efficiently breaks down organic material, especially the green (high nitrogen) matter in decomposing plant materials, and are considered to beneficial.
The adult flies are about 3/4” long, and are shiny black, looking more like a wasp than a house fly. However, these are not a pest or nuisance fly since they have no functioning mouth parts and therefore cannot bite, nor do they have a stinging mechanism. They flit about the garden, intent on their sole purpose; finding suitable sites for laying eggs which are deposited in batches of 600-800 at a time. There are far fewer nuisance flies around when Black Soldier Flies are present since the soldier flies devour the larvae of other species, and it has also been noted that significant reductions in levels of E. coli and salmonella are present in chicken manure when it has been processed by Black Soldier Fly larvae.
They like warm, moist conditions (e.g. rotting apples), and when the larvae hatch they feed voraciously on pretty much anything so long as those conditions are met; kitchen waste (they love coffee grounds), animal manure and carcasses, deserted bees' nests, and even dead fish as seen in this video: https://www.youtube.com/watch?v=DhR2jDS2IJI . The larvae are a pale beige with darker rings around the body segments, but as they mature they become a dark grayish brown. They can eat twice their body weight daily and soon convert kitchen vegetable waste into little fat bodies containing up to 43% protein and 35% fat. This makes them ideal food for chickens, and many chicken keepers farm them for this purpose. The larvae are also dried and used as food for exotic pets and fish. As they prepare to pupate, they tend to move upwards in order to leave their wet environment, searching for drier debris or soil until they mature as flies. This trait is put to good use since the mature larvae can easily be collected as they migrate out of their initial food source.
They do have a downside in some situations. Unfortunately, although Black Soldier Fly larvae and red worms both like the same food, the fly larvae are extremely active, like warm, moist conditions, and tend to make the soil acidic which is not good for worms, so if you have worm bins it is prudent to check them from time to time and remove any Black Soldier Fly larvae that may be present.
The frass that black soldier flies produce makes a clean, odor-free compost, but in my experience the food conversion into the body of the insect is so efficient, there is not a great volume of compost remaining! Dried larvae may also be pulverized and used as fertilizer.
For further reading on this subject:
https://en.wikipedia.org/wiki/Hermetia_illucens