- Author: Kathy Keatley Garvey
It's beginning to look a lot like...Halloween.
If you haven't noticed, stores are gearing up for Halloween with assorted ghosts, goblins and ghouls for you.
We remember Halloween 2023 when a female migratory monarch fluttered into our pollinator garden. She checked out the milkweed (we had several native and one non-native species) and chose to sip nectar on the tropical milkweed, Asclepias curassavica, a non-native.
We managed to capture several images of her around 5:30 p.m. before she left on her journey to overwinter in coastal California.
The Center for Biological Diversity, headquartered in Tucson, says on its website: "Across their range, monarchs are threatened by pesticides, climate change, ongoing suburban sprawl, and fragmented and poisoned habitats as they navigate their way across the continent. They need a helping hand from the government, businesses and concerned individuals."
Threats? To that we'd add a minor threat: such predators as birds, spiders and mantises.
Monarchs in western North America overwinter in coastal California (roosting in eucalyptus, Monterey pines, and Monterey cypresses), while those in eastern North America "have a second home in the Sierra Madre Mountains of Mexico" (roosting in oyamel fir forests), as noted by the U.S. Forest Service.
"Researchers are still investigating what directional aids monarchs use to find their overwintering location," the U.S. Forest Service says. "It appears to be a combination of directional aids such as the magnetic pull of the earth and the position of the sun among others, not one in particular."
We're glad to see that the raging controversy over native vs. non-native milkweed is subsiding a bit, as the more crucial threats are pesticides, habitat loss, and climate change. After all, tropical milkweed, a native of Mexico, has been in California for more than 100 years. And longer than that when you consider that California was once part of Mexico. A. curassavica is also native to Central America (including Belize, Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, and Panama) and South America (including Colombia, Ecuador, Peru, and Venezuela), according to Johnny Butterflyseed.
- Author: Cynthia Zimmerman
“Well, I must endure the presence of a few caterpillars if I wish to become acquainted with the butterflies.” ? Antoine de Saint-Exupéry, The Little Prince
Monarch butterflies are more than beautiful; they contribute to the health of our planet by feeding on nectar and pollinating many types of wildflowers. They are also part of nature's food chain as an important source of food for birds, small animals and other insects. Monarchs are considered an ‘indicator species,' which means it's the canary in the coal mine. Its sensitivity to climate change, harmful chemicals and habitat destruction send a signal to address these conditions before there is more damage to the environment.
Due to the decline of monarch butterflies and their shrinking migratory paths in the United States, home gardeners are being encouraged to plant milkweed. Why milkweed? Monarchs cannot survive without milkweed. The females only lay their eggs on milkweed as they migrate. To grow and develop, the monarch caterpillars need milkweed plants.
Before you run to the nearest garden shop, nursery or box store garden center to help the plight of the monarch, there is something you should consider. There are many, many milkweeds on the market, some native and some tropical. The Monarch Joint Venture, Xerces Society and the U.S. Fish and Wildlife Service, all of which are dedicated to saving monarchs, all recommend only planting milkweed varieties that are native to your location.
Native milkweed in California typically flowers between late spring and the end of summer. Following seed dispersal, the above-ground portion of the plant dies back to the ground remaining dormant through the winter. In spring it re-emerges from the established root system.
Many of the varieties being sold are tropical milkweeds, which are not native to the U.S. and have foliage year-round when it grows where winters are mild and adequate moisture is available (in this circumstance, Fresno is considered mild). Research suggests that the tropical milkweed may encourage monarchs to lay eggs outside of their regular breeding season, disrupting their migratory cycle, and increasing the prevalence of monarch infection by the protozoan parasite Ophryocystis elektroscirrha, aka “OE.” If you have already planted a tropical milkweed in your garden, it is suggested that you cut it to the ground in fall when natives would be dying back. It should re-emerge in the spring. This would prevent the female from laying eggs at the wrong time in their migration.
The following California species should be your first choices when planting milkweed in Fresno, Clovis and surrounding areas:
- Butterflyweed (Asclepias tuberosa) – sometimes called Orange Milkweed. Large flat-topped clusters of yellow-orange or bright-orange flowers. Blooms May to September. Needs sunlight. Drought tolerant, dry or moist soil. 1-2 ft. tall.
- Antelope-horns Milkweed (Asclepias asperula) – Also known as Spider Milkweed. Pale greenish-yellow flowers, tinged with maroon. Blooms March to October. Needs sunlight, dry or moist soil. Medium water use. 1-2 ft. tall.
- Showy Milkweed (Asclepias speciosa) – Blooms May to September. Blue-green leaves and spherical clusters of rose-colored flowers. Shade tolerant, needs some sunlight. Medium water use. Moist soil. 1 ½-3 ft. tall but can reach 6 ft. under favorable conditions.
- California Milkweed (Asclepias californica) – Native to Central and Southern California. White-wooly plant and deep purple flowers. Blooms May to July. Drought tolerant, dry slopes. Maximum height 3 ft.
- Mexican Whorled Milkweed (Asclepias fascicularis) – aka Narrowleaf milkweed. Clusters of greenish-white flowers often tinged with purple. Blooms June to September. Needs sunlight. Drought tolerant. Dry to moist soil. 1-2 ½ ft. tall.
- Desert Milkweed (Asclepias erosa) – White to yellow flowers. Green to yellow stems. Blooms April to October. Best grown in desert conditions of sandy soil. Needs sunlight, dry soils. Not shade tolerant. 1-3 ft. tall.
Although milkweed does contain toxins, it is not usually a significant threat to animals or humans. Milkweed has a foul taste and is not likely to be consumed by pets or children in a quantity that would prove harmful. Still it is best to prevent accidental ingestion by teaching children to avoid contact with the plant and to wash their hands if they do touch it. If animal or human poisoning is suspected, call the poison control center or seek medical help.
For more information on milkweed and monarchs go to the following websites:
- Milkweed for Monarchs
- Native Milkweed by State
- Milkweed FAQ
- Monarch joint venture chart
- Journey North Tracking Migrations
- Pollinators – Monarch Butterfly
Originally written November 2019. Updated May 2024.
- Author: Kathy Keatley Garvey
It lived--and quite hidden at that--through the freezing cold, the rain, and the wind. It surfaced today on a milkweed in our Vacaville pollinator garden.
Surprise, surprise! We neither saw it as an egg nor as a tiny caterpillar.
"Most larval mortality in monarchs occurs in the first 2 or 3 instars.. so they keep as hidden and low-key as possible," entomologist David James, an associate professor at Washington State University, told us. "Once they make it to the fourth instar, they are emboldened and are more likely to be seen exposed."
James, who studies migratory monarchs, earlier commented on the fall breeding: "The egg laying females you are seeing now are likely migrants that have eschewed reproductive dormancy for reproduction. This has probably always happened to some extent but is likely more significant now because of warmer falls. The lack of activity in summer in Vacaville was probably a function of most of the population having dispersed further east and north, maybe more than usual? They surely did pass through Vacaville in spring on their way north but clearly didnt stop to use your milkweeds. It does seem that some years they are more prone to frequent stopping/oviposition on their way north and east, yet in others they just keep flying. There's evidence that the latter was the case this year... with as many migrants making it to BC as to Washington...Normally they stop in Washington and only a handful make it to BC."
James is the author of a newly published book, The Lives of Butterflies: A Natural History of Our Planet's Butterfly Life (Princeton University) with colleague David Lohman of the City College of New York. The book, released in the UK on Oct. 3, 2023, will be available in the United States starting Jan. 9, 2024.
Irish scientist Éanna Ní Lamhna recently interviewed the WSU entomologist in a podcast on RTÉ, or Raidió Teilifís Éireann. The book, Lamhna said, "showcases extraordinary diversity of world's butterflies, while exploring their life histories, behavior, conservation and other aspects of these most fascinating and beguiling insects." (See Bug Squad blog). Listen to the butterfly podcast here:
https://www.rte.ie/radio/radio1/clips/22294525/
Meanwhile, we checked another milkweed plant in the garden today and spotted another caterpillar, this one a little smaller and less active than the first.
As UC Davis distinguished professor Lynn Kimsey, director of the Bohart Museum of Entomology, commented: "So much for diapause!"
Now our milkweed garden includes scores of hungry aphids, several species of milkweed, two 'cats, and maybe three (one 'cat went missing and is probably j'ing somewhere) and four chrysalids.
Will we have a Merry Chrysalis?
- Author: Kathy Keatley Garvey
Question: What's better than seeing a monarch butterfly?
Answer: Seeing two monarch butterflies sharing the same blossom on a butterfly bush!
Scenario: Monarchs (Danaus plexippus) from the Pacific Northwest are fluttering through Vacaville, Calif. and stopping in our pollinator garden for some flight fuel before heading off to their overwintering sites along coastal California.
Background: I am watching for tagged butterflies from the migratory monarch project of Washington State University entomologist David James. (After all, one tagged by his citizen scientist Steven Johnson of Ashland, Ore., on Aug. 28, 2016, fluttered into our yard seven days later. James said it flew 285 miles in 7 days or about 40.7 miles per day.)
Menu: In our pollinator garden, the flight fuel includes nectar from the Mexican sunflower (Tithonia rotundifola), tropical milkweed (Asclepias curassavica), butterfly bush (Buddleia davidii), and Zinnias, a genus of plants of the tribe Heliantheae within the family Asteraceae.
Action: On Sept. 27, a male monarch touches down on our butterfly bush and begins sipping nectar. Soon, another joins him.
The two monarchs engage in what appears to be a territorial battle. It's a kaleidoscope of orange and black wings, tumbling, wobbling, recovering.
And then, wings up! The monarchs take flight.
- Author: Kathy Keatley Garvey
"More than beautiful, monarch butterflies contribute to the health of our planet. While feeding on nectar, they pollinate many types of wildflowers.--National Park Service.
Have you ever seen pollen on a monarch butterfly?
This morning a male migrating monarch, probably on its way to coastal California to an overwintering site, stopped at a Vacaville garden to sip some nectar on a Mexican sunflower (Tithonia rotundifola).
If you look closely, you can see the gold pollen.
Monarchs are not just iconic species facing a population decline, they're pollinators.
"Pollinator species, such as bees, other insects, birds and bats play a critical role in producing more than 100 crops grown in the United States," according to the U.S. Department of Agriculture. "Honey bee pollination alone adds more than $18 billion in value to agricultural crops annually."
