- Author: Kathy Keatley Garvey
That's what we've been told for years. We hear that butterflies don't like the red ones, and that they may, in fact, be poisonous to them.
We've grown both in our pollinator garden in Vacaville, Calif. Both flourished. However, we removed the red passionflower vine, P. jamesonii, because the Gulf Frits avoided it. They lay their eggs--and quite profusely, too--on our lavender passionflower (Passiflora incarnata), also called "Maypop." (In fact, every year they skeletonize them. Hungry, hungry caterpillars!)
Which brings us to the question from a reader: "I have the Maypop and Purple Passionvine, which is working well as a host plant for the Gulf Frit. I recently bought a Red Passionvine and then read it is poisonous to the Gulf Frit. Is it true?"
We asked butterfly guru Art Shapiro, UC Davis distinguished professor of evolution and ecology, who has monitored butterfly populations in Central California for more than four decades and publishes his research and observations on his website.
"They don't use some of the red-flowered species," Shapiro says. "I don't know if they're actually poisonous. I've never found the bug on P. jamesonii around Ohlone Park in Berkeley, where there's tons of it. There's a large plant at the northwest corner of 3rd and B in Davis that may be this species, and they don't use it, either."
P. jamesoni, also known as "Coral Seas," (one of some 500 varieties in the world, see Wikipedia for the full list) is indeed striking with its brilliant red flowers.
As an aside, P. jamesoni is listed on the IUCN Red List of Threatened Species. That would be the International Union for the Conservation of Nature, which describes itself "an international organization working in the field of nature conservation and sustainable use of natural resource an international organization."
Justification for Being on the Red List:
"Passiflora jamesonii is endemic to the Ecuadorean Andes, where it is known from five subpopulations on both sides of the range. Only one subpopulation is inside Ecuador's protected areas network. The species seems to prefer untouched areas, so fires are a severe threat," according to the IUCN Red List.
- Author: Kathy Keatley Garvey
Ask away at the Science Café.
This is an informative scientific presentation held the second Wednesday of each month in the G St. Wunderbar, 228 G St., Davis. The scientist delivers a brief talk and then engages the public.
Next Wednesday, Oct. 10, biodemography expert James R. Carey, a UC Davis distinguished professor of entomology and an expert on human aging (as well as insects!) will speak at 5:30 p.m. on "Are There Upper Limits to Human Lifespan?"
How long can humans live? Well, supercentarian Jeanne Calment of France (1875-1997), lived to be 122. Born Feb. 21, 1875, she died Aug. 4, 1997. She enjoyed a healthy lifestyle, prayed and exercised daily, and lived a basically stress-free life. But yes, she drank a little wine and smoked a little. She outlived her husband, daughter and grandson.
“Why do we live as long as we do (evolutionary question), why do we age (mechanisms question) and why do we die (closure question)?” Carey asks.
Some of the topics to be discussed at the event, billed as “a conversation and dialogue with a scientist,” include:
- The trends in aging research on extending human lifespan.
- Theoretical arguments for upper limits and empirical evidence in humans
- The impact of disease elimination and organ replacement on longevity
- With the changes in human life expectancy, humans are now being given a second chance-- somewhat like the proverbial cat with nine lives--after an otherwise life-ending disease or incident
- Look to nature for perspectives on the limits of “life duration,” for example 40,000-year-old frozen nematodes; hibernation and dormancy) and limits to “active lifespan.”
An internationally recognized leader and distinguished scholar in insect demography and invasion biology, spanning three decades, Carey also researches health demography, biology of aging, and lifespan theory. He is the author of a landmark study published in the journal Science in 1992 that showed mortality of Mediterranean fruit flies (medflies) slows at older ages. Earlier this year scientists confirmed that this also occurs in humans, citing the study of 105-year-old Italian women.
Carey, who joined the UC Davis faculty in 1980, directed an 11-university, $10 million, 10-year study on biodemography of aging from 2003-2013. He is also known for discovering Carey's Equality or the death distribution in a life table population equals its age structure. He teaches a popular longevity course that draws 250 to 300 students year, and recently authored a book on biodemography, to be published by Princeton University next year.
And, if you want to ask Professor Carey about medflies, he can answer those, too. He was a recent recipient of a UC Davis Academic Senate Distinguished Scholarly Public Service Award for his “outstanding research, outreach and advocacy program involving invasion biology, specifically his significant contributions on two California insect pest invaders, the Mediterranean Fruit Fly (medfly) and the Light Brown Apple Moth (LBAM).”
Professor Jared Shaw, interim chair of the UC Davis Department of Chemistry and founder of the Science Café series, will host the Oct. 10th presentation. Launched in 2012 and initially supported by the National Science Foundation, the popular series now draws support from the Department of Chemistry and Division of Mathematical and Physical Sciences and is promoted by Capital Science Communicators.
See schedule on the UC Davis Department of Chemistry website.
- Author: Kathy Keatley Garvey
The katydid, as green as the leaves around it, is feeding on a yellow rose. It is paying no attention to the circling honey bees.
The bees want nectar, not an encounter with a critter far bigger than they are.
The katydid slowly moves from one devastated blossom to a bud.
The honey bees head off for other blossoms.
Such was the scene in our pollinator garden in Vacaville, Calif. last weekend with a fork-tailed bush katydid claiming a yellow rose.
According to the University of California Statewide Integrated Pest Management Program (UC IPM), the fork-tailed bush katydid, Scudderia furcata, is a pest of fruit such as citrus, pear, nectarine, apricots, plums, blueberries and the like.
It also seems to like our yellow rose, "Sparkle and Shine," a variety related to the "Julia Child Rose." We purchased it back in 2013 at the annual May rose sale hosted by the California Center for Urban Horticulture (CCUH) at Foundation Plant Services, on Hopkins Road, west of the central campus.
Honey bees generally don't like commercial roses (they prefer nectar-rich plants like lavender, African blue basil, sedum, sunflowers, bee balm and salvia), but they do this one.
So does the katydid.
- Author: Kathy Keatley Garvey
She hides 'em and we seek 'em.
We've spotted as many as seven adult praying mantids at a time in our little pollinator garden in Vacaville, Calif., but never once have we seen any of them laying eggs.
Until now.
The praying mantis lays an egg mass known as an ootheca or a protective egg sac. But always when you're nowhere around!
Not so this time.
Late Sunday afternoon, Sept. 23, Ms. Mantis (a Stagmomantis limbata, as identified by UC Davis student Lohit Garikipati, a Bohart Museum of Entomology associate who rears mantids) decided to grace our milkweed planter with a little present.
She climbed a redwood stake, looked around, saw me (oh, no problem, you're not a predator!), and crawled over to the other side. She positioned herself upside down, bulging abdomen intact, and proceeded to do her business. A frothy cream-colored substance began to emerge. (See my short YouTube video.) When darkness fell, she was still there.
When Monday dawned, she was still there, her ootheca finished and hardening. It probably contains several hundred eggs, but who's counting? However, scientists estimate that only one fifth will survive to adulthood. Many of the nymphs will be eaten by their hungry brothers and sisters. Bon appétit?
"Now that she's deposited the ootheca, will she expire soon?" we asked Garikipati.
"It's still early on in the season, so she may lay another two or three," he said.
She may indeed. Mama Mantis continues to hang out in the milkweed, while her ootheca, like a flag on a flag pole, "commemorates" the spot.
It should be a warning sign to incoming monarchs.
The next day, we found the clipped wing of a male monarch.
- Author: Kathy Keatley Garvey
Especially those oleander aphids that suck the very lifeblood out of our milkweed plants that we're struggling to save for monarch butterflies.
Just call aphids "The Enemy of the Gardener" or "The Enemy of the Milkweed."
The University of California Statewide Integrated Pest Management Program (UC IPM) describes 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. Almost every plant has one or more aphid species that occasionally feed on it."
"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 tells us. "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."
Not only do aphids stunt plant growth but they can spread viruses. Plus, they produce that sticky honey dew they that attracts ants and other insects.
Density? We've seen aphids so dense on our milkweed stems that all we see is yellow. (Sometimes we see red!)
We recently saw them magnified on a Leica DVM6 microscope, operated by Lynn Epstein, UC Davis emeritus professor of plant pathology, at a demonstration in Hutchison Hall. (See image below)
In California, most aphids reproduce asexually throughout most of the year, according to UC IPM. Did you know that a single aphid can generate as many as 12 offspring a day--without mating?
Bring on the lady beetles (aka lady bugs), lacewings, and soldier beetles! The larvae of lady beetles and syrphid flies also do their part in gobbling up aphids.
What to do when biological control doesn't work that well? Or when your lady beetles depart? Pinch the aphids; spray them with with water; or spray them with a mixture of 1 tablespoon of dish soap (Castile liquid soap) and one quart of water. Some folks dab aphids with cotton swabs dipped in isopropyl (rubbing) alcohol but that will kill the monarch eggs and larvae as well. We've found that spraying a mixture of sudsy soap and water works best for us.
Lather is the best medicine.
