Sally Shriner (Master Gardener) and Rick Lewis (Ranger at Gross Reservoir) have been attracting Monarch butterflies to their home at 8,200’ for over 6 years.
At your elevation of over 8,000’ how do you attract monarch butterflies?
RICK: Monarchs are attracted to milkweed, Showy Milkweed (Asclepias speciosa) in our zone. It has a very distinctive flower that has a beautiful snowball formation. It has one of the best perfumes of any flower on the planet. Milkweed develops a very unique seedpod that is an elongated slipper. In the fall it turns from green to yellow. After they dry out, collect these seed pods before they pop open. The seeds have a plume attached to each seed that acts as a little parachute as it dries out, carrying it “up, up and away.”
SALLY: Take the brown seeds and plant them in the fall so they will have that cold exposure over the winter. Do not remove the feathery plume. Milkweed grows 2’ – 4’ high in well-drained soils along roadways, in sandy ditches with lots of sun. They tolerate mild winds but if excessive, may need staking. Our patch is in a sheltered area that protects the butterfly during all stages of life - egg, larvae, pupa (chrysalis), and adult. New stalks are the diameter of thick asparagus. Plants do not need much water, as spring snows and rain are usually sufficient. If it’s dry for long periods you will want to supplement. Plants will spread so allow plenty of room. NOTE: Milkweed can also be started from seed indoors. Consult the Monarch Watch website listed at the bottom of blog and follow directions on the package.
When do the monarchs move in and what happens next?
SALLY: Come August, you will hopefully start to see Monarchs land on the leaves. The butterfly will dip her abdomen on the leaf leaving a cream colored egg – a pinprick. One monarch lays many eggs in one planting area. Prior to hatching, the eggs will get darker. Look for caterpillars (larva) emerging, which first eat the eggshell, then start gorging on the leaves. The caterpillars are the size of a half a straight pin when they emerge, green with white and black stripes. They have beautiful little black antennae. As it grows it sheds it skin (molts) 4 or 5 times.
Then comes the pupa stage. The caterpillar hangs upside-down from its hind legs. They turn themselves inside out revealing a hard case – the chrysalis. We’ve had chrysalis under stools, under the eaves, in the siding…anything that they can get a hold of that protects them. This happens from August into October. They normally will not choose the milkweed for the chrysalis stage because the ichneumon wasp, earwigs and other predators see the chewed leaves and will eat the pupa. We had about 15 chrysalis survive under the leaves of nearby four-o-clocks.
RICK: The butterfly pops open the chrysalis and emerges with very compacted wings.We have had butterflies emerge after a snow. They are poor flyers when they first take off. They prefer the aspen or other plants with big leaves where they can get a good purchase for rest.
What has been your success rate?
SALLY: In the mountains monarchs will often lay eggs late. The first year we were nervous about an early storm so we brought the branches with the chrysalis on them inside. We had 38 butterflies! After they hatched, we released them at a lower altitude. We have since learned that they are very tough. Earwigs like moist, dark places and they will eat through the chrysalis. You can put out various traps to control them - no pesticides needed!
RICK: Milkweed plant produces latex, a milky substance that exudes from the veins and the leaves to protect it from being eaten from various caterpillars. The monarch larvae sequester toxic steroids, known as cardenolides, from milkweed and they use these cardenolides as a defense against predators. Adult monarchs do not eat milkweed.
SALLY: The monarchs east of the Rockies go to Mexico and those west of the Rockies go to California. They will inhabit the exact same trees that their great great grandparents left the previous year!
http://www.monarchwatch.org/index.html Education, Conservation and Research at University of Kansas includes detailed information on propagation of milkweed
http://monarchlab.org University of Minnesota’s Monarch Lab
http://www.colostate.edu/Dept/CoopExt/4dmg/Pests/earwigs1.htm Earwig controls