More Than Monarchs

Shared by Melissa Donahue, Naturalist

melissa.donahue@nashville.gov

Photos by Melissa Donahue

Early August 2021

Common Milkweed blooming

The fall session of the Monarch Butterfly Monitoring Project at the Nature Center has begun.  One day a week, from August until mid-October, I look under milkweed leaves for Monarch eggs, caterpillars and hopefully, not too far away, a chrysalis.  To my delight I’ve found that there is so much more to milkweed than Monarchs.  Let’s look at who you can find on the milkweed plant.

Milkweed Longhorn Beetle   

Large Milkweed Bugs

It’s hard to miss these brightly colored insects. Like the Monarch larva, these insects have evolved to feed on the white, sticky sap of the milkweed plant as a defense mechanism.  This sap contains chemicals that are toxic to most animals.  Large milkweed bugs  feed on milkweed plant matter, seeds, and nectar.  The adults overwinter in leaf litter.  If they live in a cold northern climate the bugs will migrate to the central states for the winter.  Some of these adults migrate north in early summer.  Eight species of the Longhorn Beetle all use milkweed as a hostplant.  These beetles make squeaking noises when disturbed by rubbing together rough spots on their thorax.  You can tell you have a Milkweed Beetle present when you see the chew holes on the tips of milkweed leaves.

Long-legged Fly

Leatherwing Soldier Beetle

Two frequent visitors to milkweed leaves are this Shiney Long-legged Fly and orange and black Leatherwing Beetle.  Both these insects are beneficial to the milkweed.  Leatherwing beetles, a type of soldier beetle, are common on milkweed flowers where they consume nectar and pollen.   Both the larva and adult stages of this insect prey on aphids and other soft bodied insects often found on milkweed. Long legged Flies are small to medium sized predators.  They are common in meadow communities where they can be seen running over leaves in search of prey, which consists mostly of smaller insects.  Males of this family often perform elaborate mating dances.

Katydid

   

    Grasshopper      

You will have to look closely to find these two insects.  Both the Katydid and Grasshopper like to hide under milkweed leaves.  Their green color is the perfect camouflage.  These insects are mostly herbivores but will eat spiders, caterpillars and other small insects if they need food.  Because these animals are shy, you can play hide and seek.  They move around the leaf and stem as you try to get a good look at them.

 

Milkweed Tussock Moth caterpillar              

The Milkweed Tussock Moth is a type of tiger moth.  The female moth lays dozens of eggs  in fuzzy clutches on milkweed leaves.  After hatching, young larvae stay together, often completely defoliating milkweed plants.  When the orange and black warning color tufts appear the caterpillars are often solitary.  Over wintering as a pupa,  this colorful caterpillar grows into a plain silver to grayish brown nocturnal moth  Like the Monarch, Milkweed Bug, and Milkweed Beetle, the Milkweed Tussock Moth has evolved to use the milkweed as a host plant.  

 Monarch egg                     

 

Monarch larva

Milkweed is known for being the host plant to Monarch butterflies.  If you see a Monarch flying from leaf to leaf she may be laying eggs.  Monarchs lay eggs one at a time on milkweed plants, most commonly on the underside of a leaf.  Watch a female monarch closely and you will be able to find the egg after she lays it.  The eggs hatch in 3 – 5 days in warm temperatures.  The caterpillars eat, grow and molt their outer skins four times going through five instars.  In late summer the caterpillars are ready to  pupate 14 -18 days after the eggs are laid.  The butterfly emerges about 10 days after the chrysalis is formed. In middle Tennessee, we see Monarch eggs in the spring and late summer.  

These are just a few of the many insects you will find on a milkweed plant.  There are many other insects as well as spiders that call the milkweed home. If you’re on a walk in the park and you come across a milkweed plant, be sure to take the time to look under the leaves and along the stems, you’ll be amazed at what you find.

Watch a video exclusively about the Monarch life cycle