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.
Over an hour or 2, they continue to hang
onto the chrysalis as they pump fluid into the wings. The young butterfly is
very vulnerable at this stage and may fall before it is able to fly. 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!
Read more:
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