- Author: Kathy Keatley Garvey
The Gulf Frit, or "passion butterfly" (Agraulis vanillae), lays her tiny, yellow eggs, singly, on her host plant, the passionflower vine (Passiflora).
The egg? It's about the size of a pin head. Look closely and you'll see it's ridged like the raised lines of sand or a miniature ear of corn.
Often a Gulf Frit will deposit her egg on a tendril, which looks like a cork screw gone ballistic. Sometimes she'll lay her egg on a leaf, a bud, a stem or a nearby wall, gate or fence. Mama, how can we find our way?
We've grown Passiflora in our garden in Vacaville for decades. Some seasons the 'cats will skeletonize the plant, eating everything--from the leaves and blossoms right down to the stems.
Some gardeners refuse to plant the passionflower vine because a stripped plant makes them look like "a bad gardener." They have been known to pluck off the hungry 'cats to "save" the plant.
We let nature take its course. Butterflies mate, eggs hatch, caterpillars crawl, chrysalises form, and the cycle starts all over again. An egg is the promise of a new generation.
Last year the predators, including California scrub jays, praying mantises, spiders, yellowjackets and European paper wasps, grabbed their share of the 'cats.
This season, no. The scrub jays have, for the most part, vanished. Hey, look at that hawk circling our yard! The praying mantises are gone. And we haven't seen a yellowjacket, European paper wasp or spider for weeks.
It's a good year for the Gulf Frits! And a bad year for the passionflower vine... It is about to be skeletonized.
- Author: Kathy Keatley Garvey
The elm leaf beetles and their larvae don't want to hold your hand--unless perhaps you're holding a elm leaf that they can eat.
A recent walk down the 200 block of Buck Avenue, Vacaville, California, revealed the damage this pest does. The stately canopied elms don't look so stately, what with the dry skeletonized leaves, the browning and the dieback.
And if you look closer, you'll see the leaves--the feeding site--dropping prematurely, and beetles and their larvae falling with them.
Infestations of these beetles can defoliate large elm trees, according to the UC Integrated Statewide Management Program's Pest Note on this pest, Xanthogaleruca (=Pyrrhalta) luteola.
Have you ever seen them? They're about 1/4 inch long, yellow to olive-green with a black stripe on each side and four black spots near the head. They are an invasive species from southern Europe, introduced here in the 1800s, and considered the most serious elm defoliator in the United States.
"Females lay yellowish eggs in double rows of about 5 to 25 on the underside of leaves," according to UC IPM. "Eggs become grayish before hatching. Larvae resemble caterpillars and are black when newly hatched and shortly after molting (shedding the old skin). After feeding, larvae become yellowish to green with rows of tiny dark tubercles (projections). Third-instar larvae grow up to 1/3 inch long and have dense rows of dark tubercles down their sides that resemble two black stripes. Pupae are orange to bright yellow."
We observed some natural enemies on site: lady beetles, aka ladybugs, and their larvae munching on the larvae of the elm leaf beetles. Yes, beetle larvae eating beetle larvae. Lady beetles and their larvae target soft-bodied insects, and not just aphids.
UC IPM says:
"The elm leaf beetle develops through four life stages: egg, larva, pupa, and adult. Adults commonly overwinter in bark crevices and woodpiles or in buildings. In spring they fly to elm foliage and chew leaves, and females lay eggs. Eggs hatch into larvae that develop through three instars (growth stages) over a period of several weeks while chewing on foliage and then crawl down the tree trunk. Mature larvae become curled and inactive (a stage referred to as prepupae), then pupate, sometimes in large numbers, around the tree base. After about 10 days as pupae, adults emerge and fly to the canopy to feed and, during spring and summer, lay eggs. The elm leaf beetle has at least one generation a year in northern California and two to three generations in central and southern California."
Elm trees with massive defoliation can weaken the tree and pave the way for diseases and damage from other pests.
If you have elm trees, especially European elm species, and you have these little buggers all over them, you might want to access the UC IPM Pest Notes to see how to manage them.
These beetles mean business.
/span>- Author: Kathy Keatley Garvey
It's a magical moment.
First an egg, then a caterpillar, then a chrysalis, and then a butterfly, Danaus plexippus.
We took some images of a monarch eclosing back on Sept. 10, 2016. It was late in the season. While other monarchs were migrating to coastal California, some were fluttering into our yard in Vacaville, Calif., nectaring on blossoms, mating, and laying eggs on milkweed, their host plant.
The caterpillar, from the first instar to the fifth instar, munches the milkweed like there's no tomorrow (maybe there isn't?), and then forms an emerald green chrysalis, dotted with gold that's reminiscent of royalty. When it turns transparent, you can see the familiar black and orange wings, a promise of what's to come.
It takes about two weeks for an adult butterfly to emerge from its chrysalis and then it slides out--swoosh!--and hangs upside down, pumping fluids into its expanding wings. When the wings dry, off it goes. Sometimes it soars high into the sky. Sometimes it just lingers.
If you're a butterfly aficionado, you never get tired of watching that magical moment when a monarch ecloses.
Here's to Independence Day and to America's favorite butterfly, the monarch.
- Author: Kathy Keatley Garvey
Our hearts are with the victims and what we can do to help.
But we briefly stepped out in the backyard yesterday (Oct. 10) in Vacaville to see a sun and sky we did not recognize. Nearby, the brightly colored orange Gulf Fritillary butterlifes (Agraulis vanillae) continued their life cycle on the passionflower vine (Passiflora), their host plant. So unreal to see:
- An egg on the tendrils.
- A caterpillar munching leaves.
- A newly eclosed Gulf Fritillary clinging to its pupal case.
- An adult spreading its wings in the eerie light, ready to start the process all over again.
Mother Nature is not kind. Neither is Father Time.
/span>- Author: Kathy Keatley Garvey
They didn't get the memo.
Summer is over. Fall is underway. Winter is coming (Dec. 21).
But the Gulf Fritillaries (Agraulis vanillae) are still laying eggs on the passionflower vine here in Vacaville, Calif. The eggs are hatching. The caterpillars are eating. The 'cats are pupating. And the adults are eclosing from the chrysalids.
And then the cycle of life begins all over again: from egg to caterpillar to chrysalis to adult.
Actually, we've seen Gulf Frits here year around--even photographed them laying eggs on Christmas Day. Gulf Frits don't go through diapause here. They mate year around.
Of course, the survival rate is low. An estimated 95 percent of all butterflies don't make it from egg to adult, scientists say.
We've seen why. Spiders, praying mantids, yellowjackets, European paper wasps, birds, diseases, and such parasitoids as tachinid flies and wasps that lay their eggs in the caterpillars or bore into the chrysalids.
If you look closely, you can sometimes see the parasitoid evidence (hole), such as the one below. Art Shapiro, distinguished professor of evolution and ecology and an expert on butterflies, says that judging by the size of this hole, it was a large parasitoid--probably a big tachinid fly or an ichneumonid (wasp).
Just part of the cycle of life...