Feeding frenzy

These will not be pretty pictures. It’s hard to say what’s eating the milkweed faster, monarch caterpillars or aphids. For a poisonous plant, the milkweed sure provides a tasty treat!

A monarch caterpillar is unconcerned about aphid damage on the milkweed.
A monarch caterpillar is unconcerned about aphid damage on the milkweed.

There are lots of things to try to get rid of aphids. I prefer squashing and cutting off the infested tops and dunking them in water before discarding. Aphids drown fairly easily. You can also dab them with isopropyl alcohol. Just don’t harm the monarch eggs or caterpillars.

I also use the relocation method. Move the tiny babies (some use a paintbrush) to another leaf and cut the infected plant’s top off.

Relocated and rushing to the underside of the leaf
Relocated and rushing to the underside of the leaf

One thing I’ve noticed, the monarchs and aphids prefer the same leaves!They must be the tastiest.

Another one on an aphid leaf.
Another one on an aphid leaf.

In less than a month the caterpillars will be butterflies and on their way.Until then, hold on milkweed!

Monarch Update

2 monarchs

We’re headed for the 4th generation of monarchs in the garden this summer. This next batch will be the ones to fly away to Mexico.  The eggs have been laid by now and caterpillars across the state are hatching on what is left of our milkweed plants. By what’s left, I mean that which has escaped the Roundup, a decrease of approximately 58% since 1999. Half of all overwintering monarchs are Midwesterners, making the loss of their primary food source a crisis

(Here’s more about it.)

There are 74 species of milkweed and 17 in Iowa.No doubt about it, these things could be called weeds. Once you get them going, they spread like the dickens from their roots. They’re poisonous too. (But the blooms smell wonderful!) The milk or latex holds cardenolides (cardiac glycosides), toxic chemicals, which make the monarchs taste bad to predators. Handle milkweed with care! However, like many natural products found in plants, these chemicals could be potential medicines both for heart failure and cancer. That’s what natural products chemistry is all about–finding things in nature that can benefit humanity. It also brings up WHY scientists dislike species loss. Besides being a tragedy from a biological standpoint and an aesthetic standpoint, it could be a tragedy from a natural products standpoint. More than butterflies will be wiped out if milkweed plants are lost forever.

Milkweeds and butterflies

two butters Milkweed loss in the US has affected monarch populations so I tried to grow some from free seeds. It wasn’t that easy. I managed to get one scraggly plant. But that was all it took. Three years later, I have a patch. Yes, it attracts monarchs and all sorts of butterflies. The flowers smell luscious–like lilacs. Here’s a Red Admiral (Vanessa atalanta) and maybe a Great Spangled Fritillary (Speyeria cybele). Milkweed contains carenolides, toxic steroids with a bitter taste. Predators that eat insects which have eaten milkweed sicken, throw up and avoid similar insects in the future. Monarchs eat milkweeds as larvae and sequester the poison for their remaining lifespans. Milkweed is poisonous to cattle, pets, and people. The milk or latex is harmful to your eye. How did I not know this? In any case, smell them, enjoy the butterflies, but watch out for milkweeds.