- Author: Kathy Keatley Garvey
Day 5 of National Pollinator Week: Meet the leafcutter bee, family Megachilidae.
It's a native pollinator, a solitary bee, and about the size of a honey bee.
Its coloration--the black-and-white banded abdomen--makes it easily recognizable.
As the name suggestions, they (the females) cut circular holes in leaves to line their nests for brood-rearing. Rosarians who enter their roses in competition aren't fond of them because of the "imperfections" in the leaves. A hole in one--or holes in many--aren't going to give them a whole lot of blue ribbons.
But having leafcutter bees in your garden is a joy. They're good pollinators and gentle bees. Leafcutter bees carry pollen on the underside of their abdomen, not on their hind legs like honey bees, do. Agriculturists manage the alfalfa leafcutter bee (Megachile rotundata) for crop pollination.
Leafcutter bees nest in natural cavities, mostly holes in soft wood or in hollow, pithy plant stems. You can also create bee condos or housing for them, drilling specific-sized holes in a block of wood.
We saw this little male Megachile foraging on Verbena. He paused for a few minutes and then took flight. Things to do and places to go...
- Author: Kathy Keatley Garvey
Don't miss the UC Davis Bohart Museum of Entomology virtual open house on alfalfa and rice from 11 a.m. to noon on Thursday, Oct. 22.
Cooperative Extension agricultural specialist Ian Grettenberger, assistant professor, UC Davis Department of Entomology and Nematology, and his second-year graduate student, Madison "Madi" Hendrick, will discuss the crops, the pests, and the natural enemies or beneficials.
The good: Think the lady beetle, aka ladybug, that can devour some 50 aphids a day.
The bad: Think the larvae of the alfalfa butterfly, a major pest of alfalfa. Other pests of alfalfa include the Western yellowstriped armyworm, beet armyworm, and alfalfa weevil. Among the pests of rice: armyworms, aster leafhoppers, crayfish, rice leafminers, rice seed midges, rice water weevils and tadpole shrimp.
The bugly: Think all the arthropods--pests and natural enemies.
The event, "The Good and the Bad: Insects and Other Arthropods in Agriculture, with a Focus on California Rice and Alfalfa," will be live-streamed on the Bohart Museum of Entomology's Facebook page. (Link to Facebook live here). Grettenberger and Hendrick will present short talks and then field questions. No personal Facebook account is required to join the session, which is free and open to the public.
As Tabatha Yang, education and outreach coordinator of the Bohart Museum, says: "This is all about the arthropods, both the pests and beneficials that they study in the rice and alfalfa fields." Most of the focus is on insects, but tadpole shrimp in rice fields also will be discussed." A virtual family craft activity on rice is also planned.
"I will be discussing some of the insect (or arthropod) problems faced by growers of rice in California and some of the challenges in managing them, Grettenberger said. "In rice, some of the key arthropod pests are tadpole shrimp, which can turn what would have been a lush stand if rice into a poor stand with a lot of floating seedlings. Meanwhile, later in the year, armyworm caterpillars, the larvae of a moth, can chew on rice leaves and destroy plants. I'll discuss some of the ongoing work to better understand and manage these pests."
Grettenberger, Yolo County Farm Advisor Rachael Freeman Long and Madi Hendrick recently wrote a piece in the UC Agricultural and Natural Resources (UC ANR) blog, Alfalfa and Forage News, "A (Virtual )Update on Worms, Weevils an Aphids in Alfalfa."
The Bohart Museum, directed by Lynn Kimsey, UC Davis professor of entomology, is located in Room 1124 of the Academic Surge Building on Crocker Lane, UC Davis campus, but is temporarily closed. The museum houses nearly eight million insect specimens; a live "petting zoo" of Madagascar hissing cockroaches, walking sticks and taranatulas; and a gift shop stocked with insect-themed T-shirts, books, posters, jewelry, candy and insect-collecting equipment. (Gift items can now be shipped during the closure.)
More information on the Bohart Museum's virtual presentation is available on its website or by contacting Yang at tabyang@ucdavis.edu.
- Author: Kathy Keatley Garvey
The Bohart Museum of Entomology at the University of California, Davis, is hosting a virtual open house dealing with alfalfa and rice.
Cooperative Extension agricultural specialist Ian Grettenberger, assistant professor, UC Davis Department of Entomology and Nematology, and his graduate student, Madison "Madi" Hendrick, will discuss the crops, the pests, and the natural enemies or beneficials at a virtual Facebook live session from 11 a.m. to noon, Thursday, Oct 22.
Yes, this applies to you. If you're a scientist or would-be scientist, you'll want to know more about these agricultural crops and the issues. If you're a consumer and like rice and ice cream (dairy cows eat alfalfa and milk comes from ice cream, you have a stake in this.
The event, "The Good and the Bad: Insects and Other Arthropods in Agriculture, with a Focus on California Rice and Alfalfa," will be live-streamed on the UC Davis Bohart Museum of Entomology's Facebook page. (Link to Facebook live here). Grettenberger and Hendrick will present short talks and then field questions. No personal Facebook account is required to join the session, which is free and open to the public.
"I will be discussing some of the insect (or arthropod) problems faced by growers of rice in California and some of the challenges in managing them, Grettenberger said. "In rice, some of the key arthropod pests are tadpole shrimp, which can turn what would have been a lush stand if rice into a poor stand with a lot of floating seedlings. Meanwhile, later in the year, armyworm caterpillars, the larvae of a moth, can chew on rice leaves and destroy plants. I'll discuss some of the ongoing work to better understand and manage these pests."
Grettenberg's fields of expertise include field and vegetable crops; integrated pest management; applied insect ecology, and biological control of pests. (See Spotlight on Ian Grettenberger.) Among his current grants:
- Protection of rice from invertebrate pests
- Insecticide resistant alfalfa weevils in the western United States: Quantifying the scope of resistance and implementing a plan to manage the threat​
- Management of key cotton arthropod pests with insecticides and acaricides, a proactive approach to prepare for the invasion of the tomato leafminer (Tuta absoluta) into California
- Detection, biology and control of the exotic Swede midge (Contarinia nasturtii) for California cole crops
- Management of the western spotted and striped cucumber beetle in melon production
- Biological control of the bagrada bug
- Insecticide resistance monitoring and evaluation of efficacy of current chemical tactics for managing aphids and thrips in lettuce
What sparked his interest in entomology? "I had biologist parents, and was drawn into entomology at a pretty young age," Grettenberger said. "I spent plenty of time looking in flowers and turning over logs looking for insects. Once I started thinking about going to graduate school for entomology, I decided to focus on the intersection of agricultural entomology and insect ecology. I wanted to work on applied issues in entomology."
Hendrick, a second-year graduate student in the Grettenberger lab, received her bachelor's degree in iInternational studies at North Carolina State University, and also spent a semester at Nagoya University in Japan (she minored in Japanese).
"I got my start in entomology completely by chance!," Hendrick related. "I needed a science credit and happened to pick a class called 'Insects and People.”' That class really helped me to reframe the way I thought about insects and appreciate what interesting little critters they are. Through that class, I was also able to get a job as an undergraduate assistant in an entomology lab. I worked in a specialty crops lab, where I developed interests in integrated pest management and invasive species. I now study insecticide resistance in the alfalfa weevil, and I'm excited to share what I've learned through this outreach event!"
Grettenberger, Yolo County Farm Advisor Rachael Freeman Long and Madi Hendrick recently wrote a piece in the UC Agricultural and Natural Resources (UC ANR) blog, Alfalfa and Forage News, "A (Virtual )Update on Worms, Weevils an Aphids in Alfalfa."
"This year, the Kearney Research and Extension Center Alfalfa and Forage Field Day went virtual," Grettenberger wrote. "Attendees did not get the chance to look out over lush fields of alfalfa or towering plantings of sorghum, but they get did an update on ongoing work in alfalfa and other forages. Our team put together a rapid-fire video to discuss what are typically the key insect pests in California alfalfa: summer worms, alfalfa weevils, and aphids."
The summer worms in alfalfa include the summer worms: Western yellowstriped armyworm, beet armyworm and alfalfa caterpillar. Another key pest is the alfalfa weevil. The trio also discussed aphids and their natural enemies, including lady beetles, aka ladybugs).
Pests of rice include armyworms, aster leafhoppers, crayfish, rice leafminers, rice seed midges, rice water weevils and tadpole shrimp.
The Bohart Museum, directed by Lynn Kimsey, UC Davis professor of entomology, is located in Room 1124 of the Academic Surge Building on Crocker Lane, UC Davis campus, but is temporarily closed. The museum houses nearly eight million insect specimens; a live "petting zoo" of Madagascar hissing cockroaches, walking sticks and taranatulas; and a gift shop stocked with insect-themed T-shirts, books, posters, jewelry, candy and insect-collecting equipment. (Gift items can now be shipped during the closure.)
More information on the Bohart Museum's virtual presentation is available on its website or by contacting Yang at tabyang@ucdavis.edu.
Resources:
- Alfalfa and Forage News: A (Virtual) Update on Worms, Weevils and Aphids in Alfalfa (By Ian Grettenberger, Rachael Freeman Long and Madi Hendrick, Sept. 20, 2020) (See video on same page)
- Alfalfa and Forage News: Natural Enemies Are Important for Control of the Aphid Complex in Alfalfa--A Case Study (By Ian Grettenberger, Rachael Freeman Long, Daniel Putnam and Rob Wilson, April 7, 2020)
- UC Statewide Integrated Pest Management Program: How to Manage Pests of Alfalfa
- UC Statewide Integrated Pest Management Program: Insects and Other Pests of Rice
- Author: Kathy Keatley Garvey
For the first butterfly, it was the right place at the right time.
An alfalfa or sulfur butterfly (Colias eurytheme) fluttered into our pollinator garden in Vacaville to sip some nectar from a Mexican sunflower (Tithonia rotundifolia). It lingered for several minutes.
But on another day, several miles away, an alfalfa butterfly wandered into a rural nursery, and splat! Nailed by a yellow sticky trap, which is used to lure, trap, monitor and detect insect pests.
Second butterfly: wrong place at the wrong time.
Note, however, that in its larval stage, C. eurytheme is a major pest of alfalfa.
"There are four to seven generations per year of alfalfa caterpillar, and each generation is closely synchronized with the hay-cutting cycle so that the caterpillar pupates before cutting occurs," according to the UC Statewide Integrated Pest Management Program (UC IPM) website. "Caterpillar populations usually result from a flight of butterflies into the field when the alfalfa is less than 6 inches tall. Extremely large numbers of adults migrating between fields are often present from June to September in the Central Valley and from May to October in the southern desert."
UC IPM points out that factors contributing to economically significant caterpillar numbers are:
- Slow and uneven growth of the crop
- Lack of natural enemies
- Hyperparasites (other parasitoid wasps attacking the natural enemy wasps reducing their numbers)
- Hot, dry weather.
Butterfly guru Art Shapiro, UC Davis distinguished professor of evolution and ecology, says 2020 proved to be a major outbreak year for the alfalfa butterfly in the Sacramento, Yolo and Solano counties. (See butterfly invasion in the Aug. 28, 2020 Bug Squad blog).
Ever seen one in a sticky trap? Often you'll see assorted--and tiny--flies, gnats, beetles, leafminers, psylids and the like. So a yellow butterfly in a yellow sticky trap really stands out.
- Author: Kathy Keatley Garvey
UC Davis alumnus Matt Forister, McMinn Professor of Biology at the University of Nevada, Reno (UNR), will return to UC Davis campus on Wednesday, April 25 to discuss the research he and his lab are accomplishing on the "colonization of alfalfa by a focal butterfly (the Melissa blue) as well as other arthropods and microbes."
Forister has titled his seminar, set for 4:10 p.m. in 122 Briggs Hall, "Understanding Host Evolution: A Case Study of Alfalfa Colonists Across the Great Basin." This is part of the weekly spring seminars hosted on Wednesdays by the UC Davis Department of Entomology and Nematology.
"Host range dynamics are central to issues that include diversification, specialization and persistence of populations in the Anthropence," Forister writes in his abstract. "Outstanding questions in this area include the relative importance of different host traits in the colonization process, as well as the underlying genetic architecture associated with the use of alternative host plants. I will cover our attempts to understand the colonization of alfalfa by a focal butterfly (the Melissa blue) as well as other arthropods and microbes. Results will include a detailed look at genetic architecture in the Melissa blue as well as ongoing work on alfalfa phytochemistry to understand how the plant manages host-associated communities." (See his lab research website)
Forister is the co-principal investigator of a 2016-2021 grant from the National Science Foundation to study "Dimensions: Collaborative Research: The Evolution of Novel Interactions within a Network of Plant, Insect and Microbial Biodiversity." The UNR portion of the $1.9 million grant is $540,000.
Keenly interested in monarch butterfly research, Forister also holds a $25,000 U.S. Fish and Wildlife grant titled "Western Monarch and Milkweed Habitat Suitability."
Among his research publications: "The Global Distribution of Diet Breadth in Insect Herbivores," published in 2015 in Proceedings of the National Academy of Sciences; and "Global Weather and Local Butterflies: Variable Responses to a Large-Scale Climate Pattern along an Elevational Gradient, published in 2015 in the journal Ecology.
Forister received his doctorate in ecology from UC Davis in 2004, studying with major professor Art Shapiro, distinguished professor of evolution and ecology. He then worked as a post-doctoral research associate from January 2005 to July 2006 at Stony Brook University, New York, and then headed to the University of Nevada to accept a position as research assistant professor from September 2006 to July 2008 with the Department of Natural Resources and Environmental Sciences.
Forister joined the UNR Biology Department faculty in July 2008 as an assistant professor and was promoted to associate professor in July 2013. His research interests include plant-herbivore interactions; specialization; speciation; hybridization; co-evolution; evolution of diet breadth; niche shifts in herbivorous insects; global change and adaptation to anthropogenic change; analyses of long-term ecological datasets; and monitoring and conservation of insects. His teaching expertise targets ecology, biodiversity, molecular ecology, biodiversity, and biostatistics.
Highly honored by his university, Forister was named the McMinn Professor of Biology in 2015, and selected the recipient of the Hyung K. Shin Award for Excellence in Research in 2014; Regents' Rising Research Award in 2013; the Mousel-Felner Award for Excellence in Research in 2012; and the Stephen Jenkins Mentorship Award in 2012.
The Entomological Society of America honored him in 2005 with the George Mercer Younger Investigation Award for "the most outstanding paper in ecology by a scientist under 40."
Forister made his mark at UC Davis, receiving a $10,000 Faulkner Fellowship, a $11,000 Zolk Fellowship, and a National Science Foundation Graduate Research Fellowship of $86,418.
He and Art Shapiro continue to collaborate on multiple projects.
(Editor's Note: This lecture will be recorded)
