Monthly Archives: February 2017

Nectar Sources for Large-Winged Butterflies of the Mid-Atlantic 

Ooooo, a monarch! It takes an erratic path across the garden, bright orange wings gliding and flapping, drifting and fluttering. It floats down and lights on a stalk of common milkweed and after a momentary pause, the dark abdomen curls and a single egg is precisely laid underneath a small, tender leaf. She repeats the process twice more. The mother butterfly discovers another stand of young shoots on the opposite side of the garden and continues her delicate dance. An egg here. Flutter flutter. Another egg gently placed there. Three years have quickly passed since I planted tiny milkweed plants and they now command ample portions of this wildlife habitat, creating a welcoming haven for monarchs—adults and larvae alike. It’s mid-summer, with clear skies and still air; the perfect conditions for butterfly spying.

A monarch caterpillar munches common milkweed (Asclepias syriaca). Plant this if you want to make more monarch butterflies.

Common milkweed (Asclepias syriaca) and monarch caterpillars go hand-in-hand.

Scrutinizing the plants that make up this front yard garden, I stand in the warming sun and consider whether there’ll be sufficient nectar for any new monarchs when nearly a month from now the miraculous four stage metamorphosis, from egg to larva to pupa to butterfly, is complete. The smaller butterflies such as skippers and fritillaries frequent a wide variety of flowers but the large-winged beauties, I’ve noticed, are slightly more discerning. What flowers do they want? This question sent me on the most colorful of journeys…

Are you gonna eat that?

Butterflies are the magical creatures gracefully flitting through princess tales and are undeniably the most beloved of all our insects. Although not the most efficient pollinators when compared to native bees and flies, butterflies nonetheless play an important ecological role.

A monarch collecting nectar on butterflyweed (Asclepias tuberosa) with proboscis extended.

A monarch collecting nectar on butterflyweed (Asclepias tuberosa) with proboscis extended.

Most butterflies live on nectar from flowers and some also receive nourishment from pollen, tree sap, rotting fruit, carrion, dung, aphid honeydew and minerals found in wet sand or dirt. They have a proboscis, a long complex food canal that is straw-like and coiled when not in use. Proboscises come in different lengths and can dictate which flower a butterfly may drink from.

What else might make one flower more alluring to a particular butterfly than the next? Scent and color can be enticing components. Some researchers also identified butterfly morphology as a factor; they found that species with a “high wing load” generally preferred clustered or nectar-rich flowers. This would explain all the swallowtails on Joe Pye Weed!

You may be tempted to plant butterfly bush (Buddleja spp. and cultivars) because you notice your neighbor’s attracts butterflies late in the growing season. Please resist the urge to do so! Butterfly bush is an introduced plant from Asia that does not support local food webs. It’s also an invasive shrub that outcompetes native flora for resources and negatively impacts all our wildlife. Some prudent states have taken steps to ban the sale of butterfly bush.

FROM EGG TO ADULT: Support a butterfly’s full life cycle

While wildflower nectar is a necessary habitat component for butterflies, other plant life such as native grasses, vines, shrubs and trees are equally crucial for food and shelter. A landscape with tons of plant diversity will help not only butterflies but also our other wild critters— great and small and every life in between.

The spicebush swallowtail caterpillar relaxing on one of its host plants, spicebush (Lindera benzoin).

A spicebush swallowtail caterpillar lounging on one of its host plants, spicebush (Lindera benzoin).

Let’s grow butterflies! It’s easy to do: just add the plant that their larvae will eat. These specific plants that caterpillars need for food are called host plants. Monarchs, as we know, require milkweed or Asclepias species to reproduce. Host plants are not optional for caterpillars and some, like those of the zebra swallowtail, the pipevine swallowtail and the monarch, have only one genus of plant that they can eat. What Do Caterpillars Eat by the Washington Area Butterfly Club lists some common butterflies and their typical host plants.

Did you know that butterflies need water, too? You can provide essential moisture and minerals by filling a shallow dish with damp sand or mud. It’s a bit of maintenance but well worth it if you spy even a tiny skipper taking a drink, as I have. And don’t forget to leave the leaf litter! There are butterfly and moth species that overwinter as egg, larva or pupa in the blanket of fallen leaves and debris. Let’s not be tossing out the butterflies we’re trying to encourage.

FLOWER POWER!

Here the spotlight is thrown on a handful of sun-loving native herbaceous plants that large–winged butterflies such as the monarch and swallowtails have been observed to frequent. The bloom times are varied, beginning in early summer and ending in fall, when late-season nectar is crucial for migrating butterflies. These lovely plants will naturally support smaller butterflies, native bees and insects, as well as other animals throughout the food web. If the plant is a known Lepidoptera (butterfly and moth) caterpillar host, that information from Doug Tallamy’s research is included as well. Remember to choose native plant species that occur naturally in your area to keep wild areas functioning. Happy butterfly watching! Continue reading