Can the larvae of lady beetles (aka ladybugs) eat aphids?
Yes, they can. And yes, they do.
We spotted some lady beetle larvae on our yellow roses today and guess what they were doing? Right, eating aphids. Eating lots of aphids.
The larvae look a little like miniature alligators, which is probably why they're often mistaken for pests.
Oooh, what's that weird-looking thing on the roses? It can't be good. Kill it!
Sadly, that's what many people do.
Lady beetles (family Coccinellidae) are beneficial insects that gobble up aphids, mites, scales and other soft-bodied insects. Check out the Quick Tips on the UC Statewide Integrated Pest Management Program (UC IPM) website for more information and photos.
And, be sure to attend the 103rd annual UC Davis Picnic Day on Saturday, April 22. It's "open house" throughout the campus. At Briggs Hall, the UC Davis Department of Entomology and Nematology and UC IPM will answer your questions about insects (as will scientists at the Bohart Museum of Entomology in Room 1124 of the Academic Surge Building). (See news story.)
Bugs. Briggs. Bohart. What could be better? Well, youngsters visiting the UC IPM booth at Briggs Hall are in for a special treat: they will be gifted with lady beetles to take home. Watch out, aphids!
Have you ever watched a lady beetle gobble up those pesky aphids? Aphids may look fragile, harmless and sluggish, but wow, can those tiny insects ever suck those juices right out of your budding roses and other plants!
The UC Statewide Integrated Pest Management Program (UC IPM) defines aphids on its website: "Aphids are small, soft-bodied insects with long slender mouthparts that they use to pierce stems, leaves, and other tender plant parts and suck out fluids. Almost every plant has one or more aphid species that occasionally feed on it. Many aphid species are difficult to distinguish from one another; however, management of most aphid species is similar."
"Aphids have soft pear-shaped bodies with long legs and antennae and may be green, yellow, brown, red, or black depending on the species and the plants they feed on," UC IPM says. "A few species appear waxy or woolly due to the secretion of a waxy white or gray substance over their body surface. Most species have a pair of tubelike structures called cornicles projecting backward out of the hind end of their body. The presence of cornicles distinguishes aphids from all other insects."
"Generally adult aphids are wingless, but most species also occur in winged forms, especially when populations are high or during spring and fall. The ability to produce winged individuals provides the pest with a way to disperse to other plants when the quality of the food source deteriorates."
Right. If you look closely, you may see the winged ones. Or see them being devoured.
For lady beetles, this is not about eating just one. it's an all-you-can-eat buffet of hapless prey. It's like the insect version of a robotic vacuum cleaner or a paper shredder of industrial strength. Or the insect version of Joey "Jaws" Chestnut, the Major League eater who reportedly trains by fasting and by stretching his stomach with milk, water and protein supplements.
Lately we've been watching the multicolored Asian lady beetle, Harmonia axyridis, go about its business of eating aphids. It's a predator with a purpose: 50 to 75 aphids a day.
It doesn't need to train.
He was just notified that he's a recipient of the UC Davis Academic Senate's 2017 Distinguished Scholarly Public Service.
"Professor Zalom is deserving of the Distinguished Scholarly Public Service Award for his outstanding leadership in state, national and international organizations focused on integrated pest management," the Academic Senate awards committee wrote. "While serving as the president of the 7000-member Entomological Society of America, Professor Zalom pioneered initiatives aimed at identifying sustainable solutions for some of the world's important insect-based problems. For example, he organized and co-chaired the 'Summit on the Aedes aegypti Crisis in the Americas' that brought together more than 70 researchers, public health officials, entomologists, and government agencies throughout the hemisphere to identify immediate steps to sustainable solutions to control the yellow mosquito that can carry dengue fever and Zika fever viruses."
And IPM? The Academic Senate pointed out:
"Professor Zalom is known globally for his leadership in the Association of Public and Land Grant Universities IPM Committee from 1999-2015, for being a founding member of the IPM Voice, which is a non-profit organization that advocates for progressive IPM that provides environmental, social and economic benefits, and for serving on the Board of Counselors of the Entomological Foundation that promotes educational programs for grades K-12. Professor Zalom's efforts in public service have contributed to the betterment of California and the U.S."
Zalom joins previous UC Davis entomology recipients Lynn Kimsey (2016), James Carey (2015) and Robert Washino (2012).
Zalom, who holds a doctorate in entomology from UC Davis, joined the UC Davis faculty in 1980 as the Extension IPM coordinator for the UC Statewide Integrated Pest Management Program (UC IPM) and then served as the UC IPM director for 16 years before returning to the Department of Entomology in 2002.
For his work in IPM, he is also the recipient of the 2017 Perry Adkisson Distinguished Speaker Award from Texas A&M. He will deliver an invited presentation, “Invasive Species, Integrated Pest Management, and One Perspective from the West Coast" on Thursday, March 30 in College Station, Texas. The annual lecture honors Perry Lee Adkisson, chancellor emeritus and distinguished professor emeritus of the Texas A&M University System. His research accomplishments are internationally known in the areas of sustainable insect control and crop protection.
“Perry Lee Adkisson is among the icons of integrated pest management, and one of the people that I have most looked up to since starting my career in entomology," Zalom said last week. "I can't adequately express how honored I am to receive this award, and have an opportunity to visit with him once again in College Station.”
Zalom, too, is an IPM icon. (See more on Zalom's work on the UC Davis Department of Entomology and Nematology website.)
An icon, for sure.
Have you checked your rose bushes lately? Along with the lush new growth, you'll probably notice a new crop of aphids. And if you look closely, probably lady beetles (aka ladybugs).
The UC Integrated Pest Management Program (UC IPM) defines aphids as "small, soft-bodied insects with long slender mouthparts that they use to pierce stems, leaves, and other tender plant parts and suck out fluids." Basically, they're pear-shaped insects with long legs and long antennae and may be green, yellow, brown, red or black "depending on the species and the plants they feed on," according to UC IPM. "Almost every plant has one or more aphid species that occasionally feed on it. Many aphid species are difficult to distinguish from one another; however, management of most aphid species is similar."
"A few species appear waxy or woolly due to the secretion of a waxy white or gray substance over their body surface. Most species have a pair of tubelike structures called cornicles projecting backward out of the hind end of their body. The presence of cornicles distinguishes aphids from all other insects."
UC IPM also says that most aphids don't move rapidly when disturbed. That's the truth! Sometimes they're just a 16th of an inch away from a lady beetle that's gobbling up their siblings.
The lady beetles in our garden today were primarily the multicolored Asian lady beetles (Harmonia axyridis), also known as Harlequin lady beetles. They're native to China, Russia, Korea and Japan. In colder parts of the world, they're considered a nuisance when they overwinter in large congregations in walls, windows or attic. They leave unpleasant odors and stains.
Friend or foe? They're more of a friend, at least here in sunny California.
A recent visitor at a camp in the Sierra Nevada mountain range witnessed a large number of wasps and stinging behavior. They crowded around the picnic tables (ah, meat!) and sipped from soda cans (ah, sugar!) She wondered if they were yellowjackets or European paper wasps.
From the description and behavior: yellowjackets.
"European paper wasps (Polistes dominula) are not scavengers," says Lynn Kimsey, director of the Bohart Museum of Entomology and a professor of entomology at UC Davis. "They only take live insects, particularly caterpillars. Western yellowjackets, Vespula pensylvanica, are serious scavengers and are major pests in the Sierra and elsewhere. Their colonies are annual, which means that fertilized new queens must overwinter in protected places until it warms enough in the spring to begin new colonies. As the new colonies are building they need a lot of protein for their babies. The larger the colonies get the more they need."
"If many new queens survived the winter because temperatures were warmer and drier than usual then there will be many colonies to deal with, all competing for food. By late in the season the colonies go more into maintenance mode, needing a lot of sugar. They aren't feeding many babies, which need protein, and the large number of adults need sugar for fuel."
"At this point, control is largely useless," Kimsey says. "Control measures need to be started in the mid to late spring and the best control method is the use of baited traps, not spraying. Also when colonies are found they need to be removed--this needs to be done at night. These wasps nest in cavities, mostly in the ground but also in attics, wall voids and hollow trees if available. The large number of stings suggests that a colony or colonies were nearby."
"So at this point it's best to hope for a long cold, wet winter," Kimsey says.
The UC Statewide Integrated Pest Management Program (UC IPM) provides a wealth of information on Western yellowjackets and paper wasps on its PestNote: "In Western states there are two distinct types of social wasps—yellowjackets and paper wasps. Yellowjackets are by far the most troublesome group, especially ground- and cavity-nesting ones such as the western yellowjacket, which tend to defend their nests vigorously when disturbed. Defensive behavior increases as the season progresses and colony populations become larger while food becomes scarcer. In fall, foraging yellowjackets are primarily scavengers, and they start to show up at picnics and barbecues, around garbage cans, at dishes of dog or cat food placed outside, and where ripe or overripe fruit are accessible. At certain times and places, the number of scavenger wasps can be quite large."
"Paper wasps are much less defensive and rarely sting humans," according the to the UC IPM PestNote. "They tend to shy away from human activity except when their nests are located near doors, windows, or other high-traffic areas."
The UC IPM authors point out that "Typically, previously mated, overwintering yellowjacket and paper wasp queens begin their nests in spring when the weather becomes warm. The queen emerges in late winter to early spring to feed and start a new nest. From spring to midsummer, nests are in the growth phase, and larvae require large amounts of protein. Workers forage mainly for protein at this time—usually other insects—and for some sugars. By late summer, however, the colonies grow more slowly or cease growth and require large amounts of sugar to maintain the queen and workers; foraging wasps are particularly interested in sweet things at this time. Normally, yellowjacket and paper wasp colonies live only one season. In very mild winters or in coastal California south of San Francisco, however, some yellowjacket colonies survive for several years and become quite large."
UC IPM has posted an informative YouTube video, "Distinguishing Between Yellowjackets, Wasps, and Look Alikes." Look closely and you can see that those European paper wasps have distinctive orange antennae. Yellowjacket antennae are black.
Or, to put it another way: Yellowjacket antennae are black, like the Oakland Raiders' logo, and European paper wasp antennae are orange, like the logo of the San Francisco Giants.