Nature News from Greater Yellowstone #41

August 18, 2022


Greetings from the mid August days as Fireweed blooms to the top of the blossom giving us a sign of impending snow!

This post I am sharing one of The Nature Education Center (in Fifield, Wisconsin) updates about Monarch Butterflies and their recent endangered status. As I read Tom’s newsletter I started wondering about the milkweeds of the Rocky Mountain West.

First, you will see Tom’s monarch update. The second part of the newsletter will show you some milkweeds we could plant as Monarch Habitat near our homes in the west.


Tom & Mary Lou Nicholls,

Nature Education Center (NEC), Fifield, WI Enjoying & Sharing the Beauty & Mysteries of Nature & Gardening with outstanding photographs & easily understood information – to help people enjoy the wonders of our natural world while promoting its preservation.




By Thomas H. Nicholls, Nature Education Center, Fifield, WI |

eNature Report No. 248, July 24, 2022

IUCN lists monarch butterfly as endangered

On July 21, 2022, monarch butterflies were classified as an endangered species by the International Union for the Conservation of Nature due to  recent dramatic population declines.

The International Union for the Conservation of Nature (IUCN) recently added the migrating monarch butterfly for the first time to its “red list” of threatened species and categorized it as “endangered” – two steps from extinct.

The group estimates that the population of monarch butterflies in North America, one of the most recognized butterflies in the world,  has declined 22 to 72 percent over the past decade, and the western population has declined by 99.9 percent between the 1980s and 2021—putting it at the greatest risk of extinction.

So far, the United States has not listed monarch butterflies under the Endangered Species Act, but several environmental groups believe it should be listed.

Nick Haddad, a conservation biologist at Michigan State University, estimates that the butterfly population he studies in the eastern United States has declined 85 to 95 percent since the 1990s and that the species could quickly become even more imperiled in a brief time.

In North America, millions of monarch butterflies undertake the longest migration of any insect species known to science. After wintering in the mountains of central Mexico, the butterflies migrate to the north for thousands of  miles, breeding multiple generations along the way. The offspring that reach southern Canada then begin the trip back to Mexico at the end of summer.

Photo by Arlene Koziol
Monarch butterflies resting at Goose Pond Sanctuary in Wisconsin on their long migratory journey to Mexico on, 9-5-19. Located one mile south of Arlington and just 20 minutes north of Madison, Goose Pond Sanctuary is a collection of restored and protected landscapes that are a haven for birds, rare plants, insects, and more. Over 260 species of birds have been spotted at this prairie pothole and its surrounding lands maintained by Madison Audubon. Goose Pond Sanctuary — Madison Audubon

Dr. Karen Oberhauser, Director of the University of Wisconsin-Madison Arboretum, a monarch researcher and conservation biologist, helped draft the IUCN assessment leading to its endangered status.

Oberhauser said monarch butterflies are imperiled by the loss of habitat caused by herbicides and other pesticides used for agriculture use. The butterflies are also impacted by climate change. In recent years, weather conditions have become less favorable for monarch survival during migration and on their winter and summer habitats. Predation, natural disease, and the cutting of trees in their Mexican wintering grounds can also take a toll.

The good news is, there are things people can do to help monarchs! Here are ideas from several sources on how you can help:

  • Plant native milkweed—The most important plant needed by monarchs to complete its life cycle
·        Plant native milkweed—The most important plant needed by monarchs to complete its life cycle
  • Create and maintain a monarch waystation with a variety flowers including milkweed for pollinators —This provides essential habitat where monarchs can lay their eggs and pollinators including monarchs can refuel with flower nectar
  • Revise roadside management practices to benefit pollinators—Roadsides offer the potential for millions of acres of viable pollinator-friendly habitat, a great resource of milkweed and an important food and egg-laying resource for monarchs
  • Reduce harm to monarchs based upon breeding and migration activity—Understanding when monarchs are present allows land managers to time management practices like mowing, burning, grazing, or targeted pesticide application when they are least likely to harm monarchs (see attachment for details)
  • Avoid using pesticides in your own garden
  • Avoid genetically engineered (GE) foods—Because GE “Roundup Ready” seeds are resistant to glyphosate, farmers spray more and more of it to get rid of weeds. The excess glyphosate used increases the amount of milkweed killed.
  • Join the fight to stop climate change–The Monarch butterfly migration is spurred by seasonal temperature changes, but changes in the weather cycle can confuse the butterfly and disrupt its entire flight cycle. With colder winters and drier summers not only is the migration at risk, but the life of the butterfly could be threatened by changes in habitat and milkweed availability.
  • Spread the word–Educate others about the monarch butterfly decline and encourage them to take these steps to protect this delicate, now endangered species
A Citizen Science Project photo

Now for some fun facts about monarchs. Did you know?

  • The monarch is the only butterfly known to make a two-way migration like birds
  • In the fall, adults of an eastern population migrate to Mexico flying up to 3,000 miles on delicate wings
  • Female monarchs can lay 100+ eggs on a single milkweed plant
  • 60 degrees Fahrenheit is the temperature monarchs need before they can warm up their muscles to fly
  • There are only 12 mountain tops in Mexico where one can find monarch butterflies during winter
Monarch caterpillar
  • The only food on a monarch larva’s menu is milkweed
  • Monarchs travel an average of 50 miles a day during their migration

A tagged monarch traveled 265 miles in a single day

  • Most monarchs typically spend only 2 to 6 weeks in butterfly form. The first 3 to 4 weeks of life are spent as an egg, as a caterpillar, and in a chrysalis
  • Only some monarchs migrate. Roughly four generations of monarchs live and die in any given year. – Source: Birds & Blooms

Part 2 this post is about what is possible to plant in this vegetaion zone and how one could create monarch butterfly habitat.

everything below is reprinted from this link:

6 Types of Milkweed You Can Plant in Montana (AND One to Avoid!)

“What types of milkweed should I plant in my garden?”

Common Milkweed in Montana

This may seem like a crazy question if you’re just getting started with native gardening. Why would you want to plant a weed?!

But milkweed isn’t a weed at all. Instead, it’s a flowering plant that attracts butterflies (think Monarchs), native bees, and other pollinating insects, which is an excellent thing!

This article will give you information about common types of milkweed in your area and which ones will be best for your garden. And, keep reading to the end to learn about a kind of milkweed you want to avoid!

You will notice a USDA Hardiness Zone for each Milkweed plant in the article. This refers to areas of the US where plants do best, based on temperature. Here is a map showing the hardiness zones of Montana:

Hardiness Zones in Montana range from 3a to 6a.

6 Types of Milkweed in Montana

#1. Common Milkweed

  • Asclepias syriaca
Types of Milkweed found in Montana

Growing Information:

  • USDA Hardiness Zone: 3-9
  • Life Cycle: Perennial
  • Approximate Mature Size: 3 to 5 feet; up to 8 feet.
  • Bloom Time: June to August

Common Milkweed is the species most people think of when they hear the name milkweed. It’s a hardy perennial and one of the most common types of milkweed in Montana.

Milkweed gets its name from the latex or milky white secretions produced if the stem or leaves are broken. The leaves are oval, about six to eight inches long, and dark green.

Milkweed species that live in Montana

The blooms of the Common Milkweed plant are clusters of tiny flowers on stems that radiate from the larger central stem. These clusters are called umbelsThe fragrant flowers are greenish-pink, pink, or purple and give way to 4-inch seed pods in the late summer and early fall. Initially, the pods are green but slowly mature to brown. Eventually, they split open, revealing seeds and fluffy white material called coma that allows the seeds to disperse on the wind.

Common Milkweed is an incredibly important wildflower in Montana.

Over 450 native insects feed on the nectar, sap, leaves, and flowers. In addition, it’s an important food source for caterpillars of the Monarch Butterfly (Danuas plexippus). The adult butterflies lay their eggs exclusively on members of the milkweed (Asclepias) family

Common Milkweed species in Montana

Interestingly, all milkweed species contain cardiac glycoside compounds. Monarch Butterflies and other insects consume milkweed and store the compounds in their bodies. Potential predators have learned to steer clear of Monarchs to avoid this dangerous and bitter poison!

Common Milkweed is relatively easy to grow, and it’s one of the easiest ways you can help support Monarch Butterflies. You’ll need a place that receives full sun for planting. Common Milkweed does best in well-drained areas but isn’t picky about soil and can be grown in clay, loamy, or sandy areas. They tolerate poor soils and don’t need to be fertilized. It’s essential never to use pesticides on these plants since they kill species like Monarch Butterflies.

Common Milkweed can spread by seed, or underground rhizomes, which are root colonies. This means you can add Common Milkweed to your garden by directly sowing seeds or planting cuttings from an existing plant.

#2. Whorled Milkweed

  • Asclepias verticillata

Growing Information:

  • USDA Hardiness Zone: 3-10
  • Life Cycle: Perennial
  • Approximate Mature Size: 1 to 3 feet
  • Bloom Time: May to September

Whorled Milkweed is the most broadly distributed milkweed species in Montana.

This unique perennial is sometimes overlooked by gardeners who want to plant milkweed. Compared to other varieties, it has a narrow stem and spiky leaves arranged in a spiral pattern. When not in bloom, it easily blends in among grasses.

It blooms from May to September, forming flat-topped clusters of small greenish-white flowers on the end of each stem. The flowers attract various insects, including bees, wasps, butterflies, skippers, beetles, and flies.

Whorled Milkweed is still a welcome host plant for Monarch Butterfly caterpillars despite its unique appearance. Since this species is one of the last milkweeds to die back in the fall, it’s a great late-season host for Monarchs preparing to migrate south!

This delicate-looking wildflower can easily grow from seed, but it may not flower the first year. It can be grown in full sun or partial shade. Whorled Milkweed thrives in various habitats, including fields, pastures, roadsides, dry prairies, dry slopes, woodlands, and meadows. Unfortunately, it’s highly poisonous to livestock and is considered a nuisance weed in agricultural areas.

It grows best in dry soil of various types, including sandy, rocky, and clay soils. It can also be grown in moist, average garden soilKeep in mind that it is an aggressive spreader by seeds and underground rhizomes, so you may not want to choose this milkweed if you have a limited area for gardening.

#3. Butterfly Weed

  • Asclepias tuberosa

Growing Information:

  • USDA Hardiness Zone: 3-9
  • Life Cycle: Perennial
  • Approximate Mature Size: 2 to 3 feet
  • Bloom Time: May to September

Butterfly Weed is a showy member of the milkweed family. Sometimes called Orange Milkweed, this perennial wildflower features large flat-topped clusters of tiny flowers that grow 2 to 5 inches across. The blooms are brilliant orange or yellow.

Interestingly, its dark green leaves and stems don’t produce the same milky sap as other species of milkweed in Montana.

Butterfly Weed is an excellent choice for gardens and or wildflower meadows. The beautiful flowers are fragrant and are ideal for cut flower arrangements. They also attract native bees, butterflies, and honeybees to your garden. Butterfly Weed is also a host plant for Monarch, Gray Hairstreak, and Queen butterfly caterpillars.

This native flower is a great low-maintenance choice for the home gardener. Butterfly Weed’s deep taproots mean you’ll never need to water it once it’s established. In addition, this plant is highly drought tolerant and thrives in full sun. Butterfly Weed also does fine without any fertilization but grows best in rocky or sandy soil.

Unlike Common Milkweed, this species doesn’t transplant well and should be started from seed.

#4. Green Comet Milkweed

  • Asclepias viridiflora

Growing Information:

  • USDA Hardiness Zone: 3-10
  • Life Cycle: Perennial
  • Approximate Mature Size: 1.5 to 2 feet
  • Bloom Time: June to September

Green Comet Milkweed flower clusters form in the pocket created by the upper leaves. They’re made up of 20 to 80 small, pale green flowers. Interestingly, the yellowish-green leaves of this species vary in shape depending upon their habitat. Plants from moist sites tend to have rounder leaves, while plants from dry sites have long, narrow leaves.

In the wild, this species is often found on shaded roadsides, savannas, and prairies with moist to dry soil. In the garden, you can grow Green Comet Milkweed from seeds. It grows best in light to moderate shade but will tolerate full sun. Medium-dry to dry soil is best. Green Comet Milkweed doesn’t need rich soil and will tolerate sandy or rocky soil with low organic matter.

This species is a good choice for low-maintenance gardens as its long taproot allows it to tolerate drought well. Unlike many other milkweeds, this species is easy to prevent from spreading. It doesn’t form the large colonies typical to other milkweeds, so it’s an excellent option for smaller gardens!

The Green Comet Milkweed’s copious nectar and sweet fragrance attract many pollinators, including honeybees, native bees, and butterflies. It’s also a host plant for Monarch Butterflies, though it can be more challenging for monarchs to find because of its scarcity and preference for partial shade.

#5. Showy Milkweed

  • Asclepias speciosa

Growing Information:

  • USDA Hardiness Zone: 3-8
  • Life Cycle: Perennial
  • Approximate Mature Size: 1.5 to 3 feet; occasionally up to 6 feet
  • Bloom Time: May to September

As the name suggests, Showy Milkweed features flashy pink and white umbels or clusters of small flowers. The flowers are fragrant, and individual flowers look a bit like crowns. In ideal conditions, Showy Milkweed may grow as tall as 6 feet!

As a garden plant, Showy Milkweed has the benefit of being a less aggressive spreader than most other milkweed varieties in Montana. It can be grown easily from seed or the cuttings of an existing plant. It’s very drought tolerant and can be grown in a wide range of soils.

Like other milkweeds, Showy Milkweed attracts native insects and Monarch Butterflies to your yard or garden. Monarchs will visit the flowers for nectar and lay eggs on the plants, which are host plants for the Monarch caterpillars. It will also attract beautiful Queen and Viceroy butterflies to your property!

#6. Swamp Milkweed

  • Asclepias incarnata

Growing Information:

  • USDA Hardiness Zone: 3-6
  • Life Cycle: Perennial
  • Approximate Mature Size: 3 to 5 feet
  • Bloom Time: June to October

As the name suggests, this moisture-loving perennial is typically found growing wild on creek banks and ditches or in openings in swamps, bogs, marshes, and other wet areas. So if you’re looking for a plant for the wet spot in your yard, Swamp Milkweed is a perfect choice.

This species thrives in wet, mucky clay soils. It’s great for planting around ponds or streams on your property. This species requires full sun to thrive and spreads through both seeds and underground rhizomes.

Like other milkweeds in Montana, the blooms are clusters of smaller flowers. The light pink, purple, or white flowers of Swamp Milkweed will attract various species of native bees and butterflies to your garden. It’s also a host plant for monarch butterfly caterpillars.

Tropical Milkweed

  • Asclepias curassavica

Growing Information:

  • USDA Hardiness Zone: 8-11
  • Life Cycle: Perennial
  • Approximate Mature Size: 3 to 4 feet
  • Bloom Time: March to November in temperate climates, year-round in tropical climates.

This non-native milkweed plant has become popular in recent years because of its flowers’ bright red coloring and how easy it is to plant and maintain.

Unfortunately, Tropical Milkweed planted in Montana may do more harm than good.

It carries a parasite of Monarch Butterflies called Ophryocystis elektroscirrha, or OE, which can cause defects in the wings of Monarchs. Since it doesn’t die back and can bloom late, the plant itself may also confuse Monarchs by signaling a breeding season when it’s time to migrate.

To ensure you’re planting milkweed that will help your local ecosystem and attract native pollinators, always choose a native species!

Marketers of Tropical Milkweed seeds will use the names Mexican Milkweed, Bloodflower, Mexican Butterfly Weed, Mexican Orange Milkweed, and Semi-Tropical Milkweed. Steer clear of all of these!

Finally, one more link to look at :

Wishing you all the best as we move forward into September.

me visting family in Canandaigua, NY


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