The Wildlife in the Willows

By Alyssa Nyberg, Restoration Ecologist at the Nature Conservancy’s Kankakee Sands

This spring, I decided to re-read The Wind in the Willows, a children’s novel by Kenneth Graham. It had been many years since I first read this story as a child – the story of a mole, water rat, toad, and badger that have wild adventures in the countryside. As spring unfolds and I roam about Kankakee Sands, I think about the charming stories, and I am reminded that indeed there is so much wildlife in the willows – real wildlife in real willows!

At Kankakee Sands we have documented 8 different species of native willows. All of our willows are multi-stemmed shrubs with flexible branches called canes and flowers in the form of drooping catkins. The pussy willow (Salix discolor) is one of the more well-known of our native willows – its fuzzy grey buds on woody stems adorn many a spring floral arrangement. You may also be familiar with a willow not native to Indiana – the weeping willow (Salix babylonica) – a tree native to Asia, with one central trunk instead of multiple thin canes, but still with long linear leaves and catkins as flowers.

The most common willow at Kankakee Sands by far is the sandbar willow (Salix interior). In fact, we have acres and acres and acres of sandbar willows at Kankakee Sands. Yikes! That can be worrisome because as we know having too much of one thing can sometimes be a bad thing, especially if it is a plant overtaking large areas and excluding the diversity of the native prairie.

But there is so much wildlife in those willows! Big wildlife all the way down to little itty-bitty wildlife, especially in these spring months.

Starting with the biggest of our wildlife… our bison love the willows. In the spring, our Kankakee Sands bison can be seen rubbing their massive hulking bodies, especially their necks and shoulders, along the multi-stemmed willows to assist with the shedding of their thick winter fur coats. In April and May, when it is time for birthing, bison cows often retreat into protection of the willow thickets to calve. In that willow thicket they may be keeping company with a deer or a rabbit who are taking shelter from predators like coyotes and hawks.

Many of our local herbivores not only shelter in the willows, but eat it, too. Deer and bison are tall enough to nibble the tender buds that grow along the branches of the willow canes. The deer and bison, along with rabbit and beaver, are known to eat entire canes as they desire the cambium layer just beneath the bark. Interestingly, there was a study by researchers from the University of Idaho and Washing State University which found that willows do not lose their protein content as drastically as prairie grasses do in late summer and the winter. So, before the big spring green-up, willows are a very valuable protein-rich food source for our local herbivores.

Two hundred and forty-seven species of birds have been documented on the 8,000 acres of Kankakee Sands, and many of them utilize willows for food, nesting and/or cover. In the spring, emanating from the willow patches are the songs of common yellowthroats, warbling vireos, song sparrows, willow flycatchers, sedge wrens and yellow warblers. If you look closely, you will often see their nests which are not constructed on the ground like those of many grassland birds, but sit a few feet off the ground the protection that the willows provide.

Doug Tallamy, author of Bringing Nature Home, writes that willows support 455 different species of butterflies and moths! That means that 455 species of moths or butterflies are eating some part of the willow when they are in the caterpillar stage. Eighty-five of those are butterfly species, such as the viceroy, mourning cloak, red-spotted purple and tiger swallowtail butterfly. Would you have guessed that some butterfly caterpillars feed on willows?!

When you hear and see bees buzzing around the willows, you know that they have broken bud and are blooming. This happens typically in April and May. More than 25 species of native bees (and non-native honeybees) have been documented on willow buds in the spring gathering nectar and/or pollen.

Feeding on all over the stems and leaves of the willows is an assortment of insects in all shapes and sizes: aphids, weevils, flea beetles, leaf beetles, ants and treehoppers, to name a few.

As you might imagine, where there is a multitude of bugs, there is a multitude of birds. Caterpillars and insects are excellent at turning plants into juicy edible protein, which can then be plucked off the plants by adult birds and fed to their nestlings. Nestlings eat only caterpillars and insects–not seeds or berries–so these willows play a vital role in the health of our prairie birds.    

This spring, as you contemplate the landscaping in your yard or your community, consider adding a willow for all the wildlife it can support:

• Prairie willow (Salix humilus) will grow in full sun or part shade, needs medium soil moisture and typically grows 4 to 5 feet tall.
• Pussy willow (Salix discolor) also likes full sun but will tolerate part shade, prefers moist soil, and grows 8 to 15 feet tall.
• Black willow (Salix nigra) will tolerate full sun to part shade conditions, needs wet soil conditions making it a good species for along waterways, and grows 30 to 40 feet tall.

This April, consider taking a walk along the Wet Prairie Trail at Kankakee Sands which winds through several willow stands in the north bison pasture. Or instead use your binoculars to gaze upon the large willow patches in the south bison pasture. Look closely. Can you see the bison fur clinging to the stems? Or the nibble marks of herbivores? Caterpillars on the leaves, bees gathering pollen, or birds singing from the branches?

It’s all there! And be sure to keep your eyes open for mole, rat, toad, and badger too! There is certainly a lot of wildlife in those willows, and you just never know who you might see!

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The Nature Conservancy’s Kankakee Sands is an 8,400-acre prairie and savanna habitat in Northwest Indiana, open every day of the year for public enjoyment.  For more information about Kankakee Sands, visit www.nature.org/KankakeeSands or call the office at 219-285-2184.

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