Due to the additional aspects of the overwintering sites as well as the size of the state of California, updates are provided by three liasons: Susie Vanderlip for Southern CA, firstname.lastname@example.org, Diana Magor for Central CA, email@example.com and Tora Rocha for Northern CA, firstname.lastname@example.org. Please contact them for additional information.
OBSERVATIONS FOR SOUTHERN CALIFORNIA | APRIL - JULY 2020
Southern California is having a robust monarch butterfly season thus far (April thru July 2020). Reports from Long Beach to San Diego indicate that 300% more monarchs than last year are present. Monarchs are in flight across my personal garden every single day which has not happened for 3 years. Others across Orange County from Orange to Dana Pt report similarly. For the past 3 years, many reported they weren’t seeing any monarchs in their gardens or when out and about. This year, it is a regular happening, and most encouraging.
In my own garden, I have reared 70+ monarchs whereas last year, I reared only 3 from eggs on plants. Most eggs weren’t fertile. So, in the past 3 years, I adopted and raised caterpillars from one friend that had a brand-new butterfly garden and had a lot of caterpillars. From the dearth of monarchs in my garden and in other people’s gardens that were more than 2 years old, I was beginning to believe that after a monarch garden is a few years old, monarchs may not return - maybe due to older milkweed plants, maybe due to a preference for new gardens, maybe because so many more people were planting milkweed that monarchs weren’t finding everyone’s garden as readily. All that theorizing is dispelled this year. I have more than enough monarchs flying over daily, eggs, and caterpillars to really enjoy raising them once again. I have purchased several new habitats in which I put milkweed plants with caterpillars and successfully raise free of tachinid flies.
In addition, in canvassing others in southern California via social media, people remark about the volume of monarchs they are seeing in their gardens and the volume they are rearing in habitats/home gardens as well. Two to four monarchs fly back and forth over my townhome Monarch Waystation every day for the past 6 weeks. That has not happened in years. I have eggs laid weekly and caterpillars in habitats continuously.
Again, others I know who raise monarchs in their gardens are having similar experiences.
Lastly, regarding the tachinid fly. As usual for the last 5 years, tachinid flies were not present in my garden April thru mid-June. I was able to let monarch caterpillars create chrysalids on their own outside the habitats until late June. At that time, tachinid flies would show up and lay eggs in caterpillars and chrysalids, thereby killing them. by late June, every caterpillar I found was placed into a habitat for successful rearing. That is the same this year.
For those raising monarch caterpillars in habitats, something important for everyone to know. Monarch caterpillars shed their skin 5 times in the 2 weeks they are larva. The last time, of course, is to make the chrysalis. Caterpillars will commonly crawl off the milkweed to hide while shedding, and they must NOT be disturbed during this 24 to 48-hour process. The caterpillar will attach itself to a surface with silk threads to assist in its shed. Moving a caterpillar back onto the milkweed before it completes the shed will interrupt the process and can kill them. Also, while in the shed process, moving a caterpillar can damage parts of their body and result in death as well. I observed this clearly when Instar 1 thru 3 cats crawled off the milkweed plants and up the sides of the habitat where they attached and hung very still for 1 to 2 days to shed. Sometimes, I observed the shed skin left behind on the side of the habitat and sometimes it was eaten by the caterpillar before returning to the milkweed. So, for those who wonder, “Where did my caterpillars go?”, they may be off the milkweed to do their shed. Just be patient and watch for their return.
My name is Susie Vanderlip, and I have been raising monarch butterflies in my garden in Orange, California for over 10 years and give talks throughout California on monarch butterfly life cycle, butterfly gardening and decline issues over the last seven years.
As a result, I speak to many people raising monarchs, answer many of their questions, and gather data on what others are experiencing raising monarch butterflies in southern California. I share here some of the major issues.
MORE AND MORE
Many people in southern California are eagerly planting milkweed and nectar plants to try to help save western monarchs. The enthusiasm is alive and well in many homeowners.
THREE ISSUES IN SOUTHERN CALIFORNIA WORTH NOTING:
1. Prevelance of Tropical Milkweed
There are many microclimates in southern California, most very conducive to raising monarchs and to growing tropical milkweed. I became a Monarch Butterfly Citizen Scientist after O.e. killed many of my newborn monarchs in my 3rd year of raising monarchs (2013). I was only growing tropical milkweed at that time because it was the all I was aware of as I shopped in Home Depot, Lowes and Armstrong Garden Centers – which I shall call the Big 3. I bought and planted it in the ground and in pots.
Since then I have learned about the microscopic parasite O.e. that attaches to monarch butterflies and that monarch caterpillars ingest. Too much O.e. in a caterpillar may result in the birth of deformed butterflies that cannot fly which would cause them to die within a few days from starvation. O.e. accumulates on tropical milkweed leaves and, because tropical continues to leaf out year-round, the O.e. can accumulate to dangerous levels for monarch butterflies. Monarch Health at the Univ of Georgia, where O.e. is studied, concluded that it is critical to prune tropical milkweed to 8” and strip off the leaves every year by Oct. 31st to eliminate the O.e. at the end of every monarch season.
Native milkweed naturally dies back in early November, eliminating the O.e. problem. In early November newly eclosed (emerged) monarchs don’t find any more milkweed and are triggered to migrate to central coast California and overwinter (semi-hibernate for 3 to 4 months). It is thought that migration eliminates the weaker, unhealthy monarchs and is, therefore, good for the overall strength of the population.
It is important then to inform and educate southern Californians who are raising or want to raise monarchs to either plant only native California milkweed or religiously prune tropical milkweed in their gardens by Oct. 31st every year.
IMPORTANT NOTE ABOUT IMPACT OF GLOBAL WARMING.
Global warming is causing monarchs to return to southern California earlier in March than in past. As a result, milkweed needs to be present for the females to lay eggs on. Tropical milkweed is leafing out by then though native California milkweed is not.
PROGRESS: In Jan. 2020, I contacted Altman Specialty Plants which is a primary supplier of tropical milkweed to Home Depot, Lowes and Armstrong Garden Centers (the Big 3) about the need to prune tropical to protect monarch butterflies. To my delight, they were eager to help and created a tag for the tropical milkweed they sell to the Big 3 that informs buyers to prune the plant by Oct. 31st, encouraging responsible use of tropical milkweed.
Continued education of southern California public about responsible pruning of tropical milkweed is important to raise as many healthy monarch butterflies as possible.
2. Decline in Monarchs
Over the last 4 years, southern Californians raising monarch butterflies consistently report seeing fewer and fewer monarch butterflies March thru October. They do not show up in the same places every year either.
There are several reasons for the decline. One of the avoidable issues is residential use of pesticides and pesticide use by landscapers for Homeowner Associations (HOA) and cities. It is important to educate homeowners, landscapers, cities and HOA’s in southern California about the damaging effects of glyphosate/RoundUP and neonicotinoids (neonics) which are killing off all pollinators from bees to butterflies. Also educating on the critical nature of pollinators to our food supply, flowers and the beauty in our world.
It is hopeful to share that Home Depot has eliminated 99.9% of the neonic sprayed products. They still sell a few select Citrus sold in CA that must be sprayed with a specific Neonic insecticide in order to be able to sell it due to the Asian Citrus Psyllid. It is the only known insecticide to control that bug and CA Ag is doing everything they can to prevent the spread. This information was provided by the Home Depot Senior Merchant who purchases for directly for Southern CA, HI, Guam, and Las Vegas and oversees plants being purchased in all states west of the Rockies.
3. Tachinid Flies
The presence of tachinid fly predators in homeowner gardens has increased multi-fold over the last 4 years. The following pattern has been reported by many monarch butterfly gardeners in southern California.
First year of a Monarch Butterfly Garden - Many monarch butterfly eggs are laid, many healthy caterpillars, and many new monarchs. Happy new monarch butterfly gardener
Second year - Fewer monarchs and signs of tachinid fly predation by mid to late summer and increasing into October. Concerned monarch butterfly gardener
Third year and beyond - Tachinid flies are every present and raising monarchs in habitats either outdoors or inside because nearly every caterpillar/chrysalis dies with a white string indicating maggots have been forming inside. Distressed butterfly gardener now buying more and more habitats.
Apparently, tachinid flies were introduced into the western US several years ago for agricultural purposes - to kill insects that attack crops. Unfortunately, they lay their eggs in monarch butterfly larva and chrysalids, killing them. There is no known way to eliminate them. As a result, many home gardeners raise monarchs in butterfly habitats (mesh cages) to protect them from the tachinid flies and be able to rear healthy monarch butterflies. The probability of the monarch surviving from egg to adult outside of a habitat is approximately 5%. With the habitat, the probability can be as high as 95%.
Healthy Habitat Education: Raising monarchs in habitats does require some health practices on behalf of monarchs. It is important to keep habitats free of frass (monarch poop) daily, cleaning habitats after raising of a butterfly with a 10% bleach to water solution, and other options like cleaning milkweed leaves taken from plants to feed inside habitats. Details on all these practices can be found at links below.
Several Facebook groups of people raising monarchs across the country can provide helpful anecdotal guidance and enjoyable collaboration. Two such Facebook groups are: monarch.me and The Beautiful Monarch.
MONARCH SIGHTINGS AND ACTIVITY IN NORTH CENTRAL CALIFORNIA (South to North)
Monterey area: Scott Hennessy, who has a ranch in Corral de Tierra 10 miles east of Monterey, had no monarchs this Spring, despite abundant milkweed, till a couple of males stopped by at the end of July.
Santa Cruz: I estimate that the numbers in Santa Cruz are in the high 100's. Monarchs have been active in the Santa Cruz area, including mating and ovipositing, all Spring and Summer to date, (Aug 1, 2020). Monarchs are present in all areas Diana has visited in the City and surroundings since the breakup of the overwintering clusters in late January through February. The # of monarchs and ovipositing has increased in the last week or so, possibly due to the change in the weather from foggy most or all of the day (typical July weather) to fog in the am, clear, sunny and warmer (70's to 80's F) in the afternoon last week. The fog followed a very hot spell in late May and June, (in the 100's) but the #s didn’t increase noticeably at that time. Approximately 8 different monarchs enter my garden on the West side daily now when it's warm or hot. There is a resident male who patrols his 'territory', and many females ovipositing here. Many are fresh, while a few are very worn, but still ovipositing. John Dayton has ovipositing monarchs in his yard in Live Oak on the East side, and thinks that there are some monarchs in Santa Cruz all year, probably mostly locally raised.
East Bay: Our contact south of Walnut Creek saw no monarchs till June 1 ("most unusual" he said), but on July 10 he wrote that the monarch population has increased dramatically in his yard since June 1, with 3 or 4 every day and much egg laying.
Oakland: Tora Rocha from Pollinator Posse, has been receiving calls from her colleagues at the Gardens at Merritt Lake, that there have been monarchs laying eggs all spring. Apparently they are still there, but the caterpillars are disappearing due to predation by the European paper wasp discussed below. Her contacts say that they are finding eggs, but no caterpillars.
Vacaville: (N.E. of SF Bay): Kathy Keatley Garvey did not start seeing monarchs in 2019 till Aug 24, and never saw eggs. She has seen "scores" this year, beginning on May 24 – "many, many more than last year", and has raised about 16 monarchs from her yard so far.
Sacramento: Dr. Arthur Shapiro, UC Davis, who saw no monarchs last year, has seen a total of 7 this year, 5 adults in Sacramento (1 on Jan 29, 2020!, the others in April, June & July, mostly males, 1 at Gates Canyon March 20, and one in Davis), but for the 3rd successive year, has seen no reproduction or early stages. Jeff Koewler, who has lived in Sacramento for years & hadn’t seen any monarchs in years, reported that he saw 2 in his yard on different dates in June.
Santa Rosa: Merle Reuser, who, with others in his neighborhood, haven’t seen any wild monarchs this Spring.
So in general, it appears that there were migrating monarchs in some areas all Spring (eg: Oakland) and none in other areas. Dr. David James, WSU, feels that there simply were not enough monarchs after last Fall's storms to repopulate a large part of their range.
WE HAVE A RELATIVELY RECENT MENACE HERE -
The European paper wasp, Polistes dominula.
The Polistes dominula is wreaking havoc on probably all caterpillars, and perhaps eggs and chrysalises as well.
It was introduced to the East Coast of the USA in about 1978, and having no natural predators or parasitoids at that time, reproduced and expanded rapidly, reaching California around 1989.
It has a couple of parasitoids & predators now, including a moth which is a brood parasite, ironically also a Lepidopteran) and another wasp, but they apparently have not slowed this wasp down much.
This paper wasp, as the name suggests, builds its "paper" nest under eaves. It is easy to identify by the yellow/orange ends of its filaments (antennae). [photo 1: European paper wasp] It's about an inch long, striped black and yellow, hangs its legs down while flying, and could be mistaken for a yellow jacket, which mostly nests underground. It will kill and gut every caterpillar it can find, leave the gut and take the rest in pieces back to its nest to feed its own larvae.
A friend has lost virtually all the monarch cats in his yard (probably 100's) over the last couple of years, thinking yellow jackets were responsible for the carnage. He has a wasp trap up, but the invading paper wasps aren’t very attracted to traps. He showed me a video he took of one consuming one of his 5th instar cats. John Dayton, who knows a lot about wasps as well as monarchs, identified it as Polistes dominula, and said he thought they may have become a major monarch predator.
According to Karen Oberhauser et al, Lacewings, Wasps and Flies - Oh My, 2015, they also eat pupae (chrysalises). Predation rates on larvae, prepupae (J's) and pupae ranged from 0 to 76% and possibly up to 97% in some cases. I am certainly seeing a lot in my garden now, and am catching and killing them in my butterfly net. (The first time I tried that, it stung me.) I am now collecting monarch eggs and caterpillars from the garden and raising them in mesh cages.
Dr. Shapiro noted that the European paper wasp arrived in Sacramento officially in 1989, and its numbers exploded, but after about 5 years, the populations in that area crashed. He says he has not found any major impact on Lepidopteran species in any of his transect study areas.
SPEAKING OF CAGES
I recently bought a large mesh cage (24"x24"x56") from store.raisingbutterflies.org, as well as 2 smaller round carrying cages that also work for putting the cage over an in-ground or potted plant and keeping other critters out.
The top of the carrying cages zips open all the way, so you can put the open end firmly down on the ground. It wouldn’t keep ants out though. It is 14" in diameter and is 17" tall, so doesn’t work for big plants. They say visibility is better with black, but they come in white as well.
Oe: I've had a terrible time with Oe this year. I received a flat (32) of Narrowleaf milkweed plugs from a Monarch Watch Milkweed Market nursery in Encinitas, Southern California. I should have drenched them in bleach after they arrived, but they were such tiny plugs and came from such a dedicated nursery, that I didn’t. Big mistake. They must have been infested with Oe, because every cat I fed them with it eclosed with Oe. I bought a new microscope from Amazon a few months ago (they're amazingly inexpensive – everyone who is serious about raising should get one – you need at least 4x to see the Oe spores, and 100x is better) and am testing every monarch I raise (and some that I don’t raise) for Oe and only releasing those that are clean (no Oe spores) or very lightly infected, not at the "business end" of the abdomen.
The infected ones go in glassine envelopes & into the freezer, and in the past year, I had put maybe 5 in the freezer. This spring, I imagine it's more like 30. Heartbreaking and very disappointing. Fortunately, I didn't get this shipment till May, so the earlier cats were mostly clean. Important lesson #1: Bleach new plants from nurseries, and bleach your raising containers. Outside: water the plant well, then prepare a 10% bleach solution (9 parts water to 1 part regular chlorine bleach, no color or extra fragrance).
Wrap the pot and soil in a plastic bag, wrap or tie the bag around the trunk and dunk the plant in the pot upside down over 2 sticks across the top of the bucket with the bleach solution (dunk plant only, not pot), swirl it around a bit every few minutes, and leave it for about 5-10 minutes, then lift it out, still upside down, and rinse it in 2 buckets of clean, fresh water for about 5 mins each also swirling every minute or so.
For leaves or stems, if you bleach inside, use 5% solution for 10-15 mins, same treatment, except dunk the whole leaf/stem. Let it/them dry completely outside (or for leaves, between paper towels) before introducing it/them to your caterpillars. Believe it or not, this is how the pros do it. You can check butterfly-fun-facts.com for details and photos on how to clean the milkweed plants, stems, leaves and even eggs.
Important Lesson #2: Check for Oe before releasing adult butterflies. If you don’t have a microscope, either get one or partner with someone who has one. If you can see the butterfly scales AND clearly see the smaller, football-shaped spores, that's enough magnification. We're trying to raise only healthy monarchs
I am very concerned that a lot of well-meaning folks are raising and releasing butterflies without checking for Oe. This will result in a lot of Oe-infected monarchs that may look perfectly healthy and apparently fly normally, but will increase the number of infected monarchs who will spread the disease to the healthy ones and reduce their ability to migrate long distances, eg: to our northern states.
Bleach will also control NPV, Nuclear Polyhydrosis Virus, also known as Melt, Wilt, and Black Death, which will cause your caterpillars to crawl up in your rearing container, hang, die and turn to dark black liquid. Yuck! This spreads it to any other cats in the container. In that case, follow directions in the link above, remove the caterpillar immediately, sterilize the container and put it outside in direct sunlight. 6 hours of direct sun normally kills the virus.
Oberhauser et al, 2015, and Lefevre et al. 2010 also found that Milkweed toxicity affects the outcome of interactions between monarchs and their protozoan parasite Oe, and some predators and parasitoids.
Fortunately, most of the caterpillars I raised before I got the contaminated milkweed shipment were Oe free. Also, Scott Hennessy has a lot of Asclepias fascicularis (Narrowleaf milkweed) and other native species, on his large property east of Monterey, and gave me some. He has a really wide-leaved type, which is much easier to use for raising and doesn’t die back as much as the typical Narrowleaf I'm used to. It seems to like more moist conditions and some shade. [photo 2 Scott Hennessy's "wide" Narrowleaf milkweed.] Several of my cats are being fed on his uncontaminated plants (he had no monarchs this year till July 6).
Dr. Arthur Shapiro said that Asclepias cordifolia, Heart-leaved milkweed, breaks ground early in Spring, and was used heavily by monarchs at his Lang Crossing study site (mid-elevation in the Sierras on the S. Yuba River NE of Emigrant Gap) until the plants were all killed by disease. It's also used at his Washington CA site (N.E. of Grass Valley) but there are only a couple of plants there.
Worth looking into trying to increase populations of A. cordifolia in the foothills and mountains?
Scott recently emailed that he has had very few pollinators at all this spring. People in other areas are saying the same thing. That doesn’t seem to be the case in Santa Cruz, and it's possible that the Santa Cruz "green ethic", together with the clean air coming in from the ocean, is resulting in fewer pesticides in the environment, so the insects may have partially escaped the pesticide/herbicide disaster somewhat. Just a hypothesis.
Scott Hennessy organized a project at Palo Corona, the venue of the Monarch Summit in January in Carmel Valley, in which he and volunteers have solarized a 2000 sf plot under clear plastic for 100 days in an attempt to control the former golf course turf and invasive weeds abundant on the site. He installed the plastic in February 2020.
The site is adjacent to the ½ acre plot he started in February 2019 that we visited during the monarch conference. [photo 3, Scott Hennessy's Restoration site at Palo Corona, CA] He says the site is looking very good, the Narrowleaf milkweed is thriving and he expects it to bloom soon.
He hopes to plant out 150 more Narrowleaf at the 3 2,000 sf solarized test sites once we get some rain. He also plans to collect lots of seed from his extensive milkweed collection, including A. eriocarpa, later this summer and start some more plants in early winter.
A website filled with information about monarchs and many other Lepidopteran species, how to raise them, host plants, predators, diseases, neonicotinoid use on nursery plants, etc.
Excellent website and blog and everything Monarch
Monitoring butterfly Populations across Central California for more than 35 years. Detailed accounts of butterflies and their habitats (with photos) at 10 study sites in a transect across California from the East Bay (sea level) to Sierra Valley, on the East side of the Sierra Nevada, where adults continue to emerge into October in good years.
Central Coast Loses Over Half of Its Overwintering Monarchs in Big Storm of November 27, 2019.
Santa Cruz. A severe storm the night of Nov 27, 2019, was disastrous for western monarch numbers. In Santa Cruz, it destroyed virtually all of the Natural Bridges 2,000 monarchs. Only 50 were found in a small cluster on a eucalyptus branch the following morning with most of the others dead or dying on the ground. Moran Lake declined from about 400 monarchs to about 50. The Lighthouse Field population, estimated at 3,400 on Nov 27, fared much better than the other 2 sites, losing approximately 800. The Pacific Grove population was reduced from 642 prior to the storm to approximately 316.
That story was repeated all up and down the central coast, including a large population near Big Sur and in the largest population of over 6,700 at Pismo Beach. For more details, see xerces.org/Thanksgiving count. Many long term observers said they had never seen destruction like this. The storm was exceptionally bad, as evidenced by the virtual loss of the Natural Bridges colony. The question is why. Climate change? Habitat damage?
Kids and adults alike soaking up the magic of a “Monarch Cascade” at Natural Bridges Grove.
The Lighthouse Field overwintering site consists of some Eucalyptus trees and several Monterey Cypress trees, and is protected from Southerly ocean winds by several rows of Monterey Cypress. Monarchs shelter by hanging under the boughs of the Cypress, which protects them from rain, wind and cold temps at night. The Natural Bridges site had 1 large eucalyptus in the dell where the monarchs clustered, but does not have Cypress in that spot. Where there was once a large Eucalyptus, there is now a a much smaller tree, and I did not observe any monarchs there this winter. They clustered on Eucalyptus branches higher up the hill and off the ground which swing wildly in strong winds and do not appear to provide any protection from the rain. I do not know if this is a significant factor in the loss of the Natural Bridges colony, but an assessment of the NB site and suggestions for improvements are strongly recommended.
Nectaring, Mating Behavior and Spring Migration at Lighthouse Field in Santa Cruz:
John Dayton observed overwintering monarchs nectaring on the sparse Eucalyptus flowers many times between Dec and March. Willows started blooming in late January, but the (non-native) radishes, which are usually a source of nectar, were very sparse and not yet blooming by the time the monarchs were beginning to leave, possibly he suggested, due to the very dry and windy weather we had over January-February. John observed mating late January with most of the females departing by February 18. I saw the first female in my garden 2 miles North of Lighthouse Field on Jan 25.
Monarchs clustering under Monterey cypress bows catch morning sun at Lighthouse Field.
From Feb. 1 on, I have seen between 1 & 5 monarchs in my garden daily, and on March 4, at least 17 monarchs flew through, making 1 pass, then heading North, not stopping to nectar or lay eggs on a large milkweed plant. By Mar. 8, there were only 70 monarchs remaining at Lighthouse Field, mostly males.
John observed 2 females laying eggs the first week of March. A neighbor who has tropical milkweed in his sheltered garden, had monarchs laying eggs there all winter. The caterpillars stripped his plants bare and he gave about 70 away on April 27 to people who had enough milkweed to feed them. The adults did not stay at his property overnight.
A friend in Sacramento has not seen any monarchs for years, and friends in Dublin, in the East San Francisco Bay area, have not seen monarchs for some time either. They are, however, willing to plant Native milkweeds and nectar plants. A friend in Cameron Park, in the foothills East of Sacramento, reported that he had seen 2 monarchs flying over the golf course adjacent to their property on April 24.
Tora Rocha of Pollinator Posse, has more information on Monarchs in Northern California and on Waystations.
Jimmy Panetta, our Central Coast Congressman, and 4 senators, introduced the Monarch Action, Recovery, and Conservation of Habitat Act ("The Monarch Act 2020") to Congress and the Senate in Feb, 2020. It designates $62.5M for projects to conserve Western Monarchs and another $62.5M for U.S. fish and Wildlife to implement the Western Monarch Butterfly Conservation Plan approved by the Western Association of Fish and Wildlife Agencies in 2019. Funding for both would be split into 5 year amounts of $12,500.
There are 15 milkweeds native to California. The 2 that can sometimes be found for sale in retail garden stores and nurseries now are the Narrow-leaf milkweed, Asclepias fascicularis, and Showy milkweed, Asclepias speciosa. They do take some time to establish, but it’s worth the wait. Other native species, such as Woolypod or Indian milkweed (also California Monarch Milkweed) A. eriocarpa, and Heart Leaf milkweed A. cordifolia, are available in some nurseries specializing in Ca native plants (see links below). Another milkweed that is extremely easy to find in stores is Tropical milkweed, Asclepias curassavica, which is not native, & its cultivation is very controversial (Silky Gold is a cultivar of Tropical Milkweed by the way.) It is native to much of Latin America and the Caribbean, and is not deciduous in warm climates.
Xerces Society for Invertebrate Conservation is adamantly against planting it because 1. it is not native, 2. since it is not deciduous, a monarch protozoan parasite called Oe can build up on the plant over the breeding season and increase the infection which reduces the monarch's flying ability and longevity, and can allow transmission of the spores to its offspring & other healthy monarchs and 3. possibly interfere with their migratory behavior. If you have Tropical milkweed in a garden, it is recommended that you cut the plant to the ground or within a few inches of it every year at the end of October, and continue to trim the new growth back until early January. This largely resolves the latter 2 issues, and at the same time provides clean milkweeds to mated migrating females who start their migration as soon as late January and have no other milkweeds available for egg-laying, since the native deciduous species have not yet emerged.
The other option is to grow it in pots that can be moved inside in a sunny spot, treated with a 5% Clorox bleach solution (regular strength in tap water), followed by 1 or 2 thorough rinses in tap water, and either raised in fine mesh butterfly cages or put outside. [See Frequently Asked Questions. Monarch Disease.] As one of our associates says, it is so well established in Southern California that getting rid of it is unrealistic.
Encouraged by the WMA 2020 Monarch Summit at Carmel in January, I built my own little waystation in containers on a sunny deck in Santa Cruz, and have received approval for another big one at a housing development in Scotts Valley, 9 miles inland and N of Santa Cruz, to begin shortly. I'm growing nectar plants from seed and giving them to neighbors for their monarch gardens.
Diana Magor’s container Waystation on her deck in Santa Cruz
Diana would like to hear from anyone who raises monarchs, or who is interested in growing waystations in Central California, or wants to help plant them.
Links to native milkweed and nectar plant growers & suppliers:
Las Pilitas Nursery, 3232 Las Pilitas Rd, Santa Margarita, Ca. 934553. San Luis Obispo County www.laspilitas.com. So much good information on their website. (Native plants only.)
Annie’s Annuals & Perennials, 740 Market Ave., Richmond Ca (East Bay area). www.anniesannuals.com. 888-266-4370. Amazing Spring and Summer catalogs, with great photos, fun descriptions, growing conditions, and several Ca Native plants.
San Lorenzo Garden Center, 235 River Rd, Santa Cruz, Ca. 95060 www.sanlorenzolumber.com. 831-423-0223. Local Santa Cruz garden center with good selection and many pesticide-free plants. (Special orders too)
The Garden Company. 2218 Mission St, Santa Cruz, Ca 95060. A. fascicularis sometimes. www.thegardenco.com. 831-429-8424. (Environmentally minded)
Suncrest Nursery, Watsonville, Ca. Wholesale only.
Please check the CNPS website www.Calscape.org for native milkweed sources near you.
The Monarch, Saving Our Best-Loved Butterfly. Kylee Baumle. 2017 St. Lynns Press. Pittsburg.
Field Guide to the Butterflies of the San Francisco Bay and Sacramento Valley Regions, Arthur M. Shapiro and Timothy D. Manolos, University of California Press.
A wealth of information on invertebrates including the Western Monarch Population.
www.monarchjointventure.org. Many fact sheets on all aspects of monarchs.
The Monarch Butterfly Garden. www.monarchbutterflygarden.net. Minneapolis, MN 55420. Instructions, suggestions and contacts on how to do almost anything re: monarchs: a great blog, answers questions, gives gardening tips, resources.
Professor Art Shapiro’s website on central California butterflies.
Information to be provided at a later date.
For more information on Northern California, please see contact information above.