Milkweed is more than monarch butterflies

 

Over the past 15 years or so, milkweed gardens have been the “in” thing for gardeners and nature lovers. I appreciate every one of you who have undertaken the task of growing these plants to help the beleaguered monarch regain its status as the king of our butterflies. Since the 1990s, the population of migrating monarchs has declined by 80%. Your efforts have helped to slow down that loss and, in some years, led to significant, albeit it periodic and temporary, rebounds. Keep plugging along – this war will be won via a resilient and patient group effort.

While tending to your butterfly garden, stop and smell the roses -- well, smell the milkweed. Those flowers are powerful in their scent, it’s such a beautiful aroma, reminiscent of lilac. Upon smelling it, it becomes obvious why so many pollinators and other insects love the flowers.

Those are the creatures I want you to appreciate. Monarch butterflies get all the love and attention, and deservedly so, but peer into the flowers and you’ll see an incredibly diverse and beautiful world of insect life, from beetles to bugs to bees. Your milkweed garden is an environment unto itself, one you created or stewarded to help one species, one that helps so many more.

An insect that you’re likely see is the red milkweed beetle. Elongated in shape, reaching a half inch in length, these beetles are, as the name implies, red. That brilliant crimson body has large black dots, and its head is topped off by long antennae, hence their older moniker of milkweed longhorn.

The entire life cycle of these beetles is dependent on milkweed. As larvae, they live underground, feeding on the roots of the plant. The adults eat the leaves, buds, and flowers. Because of their hunger for milkweeds, many butterfly enthusiasts see them as a pest, a threat to the monarchs. Please don’t. These native beetles have just as much right to the plants as the monarchs do. They don’t kill the plant. And fear not, they are not predatory – they won’t eat monarch eggs or caterpillars.

Milkweeds are, though, frequented by some predatory beetles. But know that they aren’t feeding on baby monarchs. Instead, they feast on insects that can harm milkweeds – specifically the oleander aphid. These tiny aphids, which are an invasive species from the Mediterranean, can be identified by their bright yellow hue and sometimes huge numbers, which are facilitated by parthenogenesis (a fancy way of saying ladies don’t need guys to make babies). These swarming aphids can suck the sap, which stunts plant growth, and they leave honeydew, which can lead to fungal outbreaks on milkweed. These aphids are consumed by ladybird beetles (also known as lady bugs) and red soldier beetles.

If you are lucky, you might see another caterpillar on your plants. The young of the milkweed tussock moth (or milkweed tiger moth) have a black body sporting locks of white hairs on the side and orange hairs along their back. Like all insects that consume milkweed they pick up chemicals from the sap that make them unpalatable to birds and bats and other non-insect creatures.

How cool are they when they grow up to be moths? Consider their superpower.

When it comes to other milkweed eaters, which could theoretically be feasted upon during the day, they are typically orange (monarch butterflies) or red (milkweed beetles). Aposematic coloring serves as a warning to predators – “see these bright colors? It means I’ll make you sick. Don’t eat me!”  

Moths fly at night, when they won’t be seen. But, they could be heard or sensed by bats. So, the moths have their own version of informing predators about the ability to sicken those who try to devour them: These moths have tymbal organs which make noises that are imperceptible to the human ear, but can toy with bats’ echolocation – informing them that they taste bad. Wild, eh?

It doesn’t end there. There’s a whole world of interesting creatures living in the milkweed garden. This summer, get closer with your plants – peer into the flowers, look on the underside of the leaves – and you’ll, in turn, get closer with countless beautiful living things.