At a recent visit to the UC Davis Ecological Garden at the Student Farm, we watched a honey bee, Apis mellifera, and a lygus bug nymph, Lygus hesperus, foraging on a batchelor button, Centaurea cyanus.
The bee: the beneficial insect.
The lygus bug or Western tarnished plant bug: a pest.
The lygus bug, which punctures plant tissues with its piercing mouthparts, was there first, but no matter. The bee joined in, edging closer and closer until they touched.
In photography insect circles, that's a "two-for"--two insects in one image.
The bee finally buzzed off, leaving the lygus bug to "dine" alone.
The lygus bug, distinguished by a conspicuous triangle on its back, is a very serious pest of cotton, strawberries and seed crops, including alfalfa. Scientists estimate that in California alone, the pest causes $30 million in damage to cotton plants each year, and at least $40 million in losses to the state's strawberry industry. The insect is also a pest of numerous fruits and vegetables, including apples, pears, peaches, eggplant, tomato, potato, artichoke, lettuce, sugarbeet, and beans. See what the UC Statewide Integrated Pest Management Program (UC IPM), says about the pest.
What do they look like? "Adult lygus bugs are green, straw yellow, or brown with a conspicuous yellow or pale green triangle on their backs," UC IPM says. "Nymphs are light green...Lygus can move into gardens or orchards from weeds, especially when they dry up. They are a particular problem in beans, strawberries, and orchard crops, feeding on developing flower buds and fruit. Fruit may become blemished and discolored, deformed, or twisted and may develop depressions or pustules."
Cotton? "Lygus bugs," says UC IPM, "migrate to cotton from other hosts, so management of this pest begins with assessing its populations outside the field. Check for them on weeds, in nearby alfalfa, and in other crops, and keep in touch with your pest control adviser, Extension agent or Farm Advisor for area-wide information on lygus bug populations. Proper management of alfalfa harvest can reduce damaging migrations to cotton."
Cooperative Extension specialist Ian Grettenberger, UC Davis Department of Entomology and Nematology, works closely with farmers in their lygus bug battles.
The feral cats on our farm (the progeny of strays dropped off by "imperfect" strangers) became known as "The Look-at-Cats." You couldn't touch, pet or hold them. You could feed them, though, and spay or neuter them--if you could catch them. And you could name them, too. "Look, there's a Look-at-Cat."
Now monarch caterpillars may be the new "Look-at-'Cats."
The troubling decline of monarchs, Danaus plexippus, has led the California Fish and Wildlife to post on its website and issue several mandates:
Conservation Status of Monarch Butterflies
"In 2014, monarchs were petitioned to be listed under the federal Endangered Species Act. In December 2020, the U.S. Fish and Wildlife Service found that listing was warranted but precluded (opens in new tab) by other listing actions on its National Priority List. The monarch is currently slated to be listed in 2024."
"In California, monarchs are included on the California Department of Fish and Wildlife's (CDFW) Terrestrial and Vernal Pool Invertebrates of Conservation Priority list (PDF) (opens in new tab) and identified as a Species of Greatest Conservation Need in California's State Wildlife Action Plan. California law (Fish and Game Section 1002) prohibits the take or possession of wildlife for scientific research, education, or propagation purposes without a valid Scientific Collection Permit (SCP) issued by CDFW. This applies to handling monarchs, removing them from the wild, or otherwise taking them for scientific or propagation purposes, including captive rearing. Due to the current status of the migratory monarch population, CDFW has also issued a mortarium on certain activities covered with an SCP. To learn more about obtaining a collection permit, see our SCP page."
What this means, according to biologist Hillary Sardiñas, senior environmental scientist and pollinator coordinator, Wildlife Diversity Program, California Department of Fish and Wildlife, is no handling or propagating them, including captive rearing, without a scientific collection permit (SCP).
As she wrote in an email today: "Monarch butterflies are a Terrestrial Invertebrate of Conservation Priority which means that handling or propagating them, including captive rearing, without a scientific collection permit (SCP) is not permitted, as described on our monarch website. We have gotten a number of questions on this topic and are currently developing an in-depth FAQ to help people understand threats to monarchs as well as what is and is not permitted. I am happy to share it with you once it is finalized. Unit then, here are answers to your questions:
- Are monarchs in a backyard considered wild? "Wildlife does not only occur on public lands, species can also inhabit private property, including backyards. Therefore, the permit requirement applies to handling activities wherever monarchs occur."
- Educational use? "A scientific collection permit (SCP) is also required for educational purposes. Therefore, the educator would need to have a valid SCP authorizing them to collect/receive and possess monarchs for this purpose. The person collecting the monarch on their behalf would also need a valid SCP or to be named on the educator's SCP. While monarchs have been an incredible tool to learn about long-distance migration and metamorphosis inspiring children and adults for generations, there are so few migratory monarchs that removing just 10 caterpillars could mean you are impacting 5% of the remaining population (estimated at <2,000 in the last overwintering census). At this time, we do not recommend moving caterpillars indoors for any purpose. If educators want to create a monarch garden so that students can observe adult butterflies lay eggs that develop into caterpillars, that scenario would provide an excellent educational opportunity while contributing to monarch conservation."
As Sardiñas, who holds a doctorate from UC Berkeley and formerly worked for the Xerces Society for Invertebrate Conservation, points out: "While monarchs used to be abundant, they are now scarce and the western migratory population has a high estimated likelihood of extinction. A shift from past actions that could cause harm to ones known to be beneficial, such as habitat creation, is required to promote their recovery."
You're encouraged to plant nectar sources and milkweed (the host plant) for the monarchs, but don't touch the eggs, caterpillars, chrysalids or adults. The 'cats, which many teachers traditionally collected to show their students metamorphosis and then released them into the wild--and which monarch moms and dads reared to protect from such predators as birds, wasps, spiders and praying mantids (and parasites)---are now "look-at-'cats."
They're out there, and you don't have to crane your neck to see them.
Some folks mistakenly call them "mosquito hawks" or "mosquito eaters," but they are neither. They are crane flies, members of the family Tipulidae of the order Diptera (flies).
We've been seeing the slender, gangly, goofy-looking insects, Tipula oleracea, bump into walls and flower pots. This one (below) glided into the tower of jewels, Echium wildpretii, and just remained there for several minutes.
Lynn Kimsey, director of the Bohart Museum of Entomology and UC Davis distinguished professor of entomology, emphasizes that they don't eat mosquitoes. "In fact, adult crane flies generally don't eat at all," she points out. "Their entire brief adult lives are spent searching for mates and laying eggs." Crane flies are attracted to lights at night and you may find them around your porch light.
"Adult crane flies emerge from the soil beneath turfgrass, pastures and other grassy areas in late summer and fall," according to the UC Statewide Integrated Pest Management Program, part of the UC Agriculture and Natural Resources.. "The adults have very long legs and resemble large mosquitoes. Females mate and lay eggs in grass within 24 hours of emerging. Eggs hatch into small, brown, wormlike larvae that have very tough skin and are commonly referred to as leatherjackets. The leatherjackets feed on the roots and crowns of clover and grass plants during the fall. They spend the winter as larvae in the soil; when the weather warms in spring, they resume feeding. During the day larvae mostly stay underground, but on damp, warm nights they come to the surface to feed on the aboveground parts of many plants. When mature, the larvae are about about 1 to 1½ inch long. Around mid-May they enter a nonfeeding pupal stage and remain just below the soil surface. In late summer, pupae wriggle to the surface and the adults emerge. There is one generation a year."
This one (below) didn't find a mate on the tower of jewels but it did find a towering view. The plant can reach 10 feet in height.
It's Earth Day, an event we celebrate every April 22 to demonstrate support for environmental protections on our troubled planet. This year's theme: "Restore Our Earth."
Sadly, however, most college campuses are temporarily or partially closed due to the COVID-19 pandemic, so the face-to-face "teach-ins" are primarily Zoom sessions. Who would have thought? Who could have known?
What to do on Earth Day? Watching bees forage in a pollinator garden seems appropriate to recapture some of Earth Day's magic. Honey bees, responsible for pollinating one-third of the food we eat, continue to gather pollen, nectar, water and propolis every day (weather permitting), not just Earth Day.
Today's favorite fauna and flora: honey bees, Apis mellifera, foraging on rock purslane, Calandrinia grandiflora and packing red pollen back to their colonies. Just call them "temporary occupants" on Planet Earth. But always call them "special."
Read NASA's Nine Reasons We're Grateful to Live on Earth, posted April 21, 2020 for a better grasp of what we have and what we could lose. "The promise of a better life in the mysterious beyond can be seductive. But the fact is the more we learn about out there the more we realize how special it is here. The first astronauts to look from space back at Earth, a 'pale blue dot, the only home we've ever known,' as scientist Carl Sagan once wrote, saw a beautiful, delicate world that is perfectly suited to the bounty of life it supports."
Happy Earth Day!
The Red Coats are coming. The Red Coats are coming.
No, not an army of soldiers. Soldier beetles.
These insects (family Cantharida) resemble the uniforms of the British soldiers of the American Revolution, which is apparently how their name originated. They're also called "leatherwings" in reference to their leatherylike wing covers.
Soldier beetles are beneficial insects; they're the good guys and gals in the garden. The adults eat scores of aphids. In addition, they are pollinators. So, don't even think of killing soldier beetles. Enlist them in your garden to feast on aphids.
"The adults are long and narrow," according to the UC Statewide Integrated Pest Management Program (UC IPM), which labels them as natural enemies of garden pests. "Common species are often about 1/2 inch (13 mm) long with a red, orange or yellow head and abdomen and black, gray or brown soft wing covers. Adults are often observed feeding on aphids or on pollen or nectar on flowering shrubs and trees. Metamorphosis is complete. Larvae are dark, elongate, and flattened. They feed under bark or in soil or litter, primarily on eggs and larvae of beetles, butterflies, moths, and other insects. There are over 100 species of soldier beetles in California."
If you want to know identify some of the natural enemies of garden pests, you can download UC IPM's educational poster, "Meet the Beneficials: Natural Enemies of Gardens" here.
The poster illustrates some of the beneficial insects, mites and spiders that prey on garden pests:
- Convergent lady beetle
(adult, larva, eggs)
- Green lacewing
(adult, larva, eggs)
- Predaceous ground beetle
- Assassin bug
- Pirate bug
- Damsel bug
- Soldier beetle
- Syrphid fly
- Sixspotted thrips
- Western predatory mites
- Predatory wasps
- Praying mantids
- Examples of parasites (including a typical life cycle)
These soldier beetles may even know how to pull rank.