Staring out at a frozen yard in January, it’s tempting to imagine that pollinator gardening is a “spring problem.” But midwinter is actually prime planning season, especially when it comes to choosing the woody plants that quietly do the heavy ecological lifting.

While summertime perennials tend to get all the glory, trees and shrubs are the backbone of pollinator support. They bloom earlier, feed more species, and hold together entire food webs. Many of them are what ecologists call keystone species: plants with a disproportionately large ecological impact compared to their abundance. And in Minnesota, no keystone species comes close to the mighty oak.

Oaks: Minnesota’s Ecological Powerhouses

If you plant only one new tree for wildlife, make it an oak. According to entomologist Dr. Doug Tallamy, oaks can host over 500 species of moth and butterfly caterpillars, more than any other plant genus in North America. Those caterpillars then feed birds, mammals, and an astonishing chain of other creatures. In other words, an oak isn’t just a tree; it’s an entire community center.

Minnesota gardeners are lucky: several oak species, bur, white, and red, among others, thrive statewide. Whether your yard is sandy, loamy, sunny, or mixed, there’s likely an oak that fits.

Other Woody All Stars for Minnesota Landscapes

While oaks steal the show, they’re not the only woody keystones worth penciling into your garden plans:

• Willows (Salix spp.)
  The earliest bloomers in spring, willows offer critical pollen just as bees and earlyemerging insects wake up hungry. They’re fastgrowing, adaptable, and perfect for damp spots.
• Birch (Betula spp.)
  Another valuable native, birch supports a long list of specialist insects and bridges that tricky earlysummer gap when little else is blooming.
• Elderberries (Sambucus spp.)
  These shrubs are pollinator magnets in bloom, and their berries feed birds well into fall. Tough, coldhardy, and great for hedgerows.
• Spicebush (Lindera benzoin)
  Famous for feeding the spicebush swallowtail, it’s a fantastic native understory shrub that boosts biodiversity.
• New Jersey Tea (Ceanothus americanus)
  A compact, droughttolerant shrub well suited to Minnesota’s sandy soils, supporting a surprising array of native insects.

Winter: The Best Time to Dream Big

January may feel quiet, but this is when great pollinator gardens begin, on notepads, sketchbooks, and the backs of seed catalogs. Think about where a new oak or willow might anchor your yard, or how a row of elderberries could replace those highmaintenance ornamentals that aren’t doing much for wildlife.

Keystone woody plants don’t just look great; they make your yard part of a functioning ecosystem. And come spring, everything from emerging bees to hungry warbler chicks will thank you.

If you’d like to dig deeper into keystone species and pollinator habitat, the University of Minnesota Extension is offering a free threepart webinar series:
https://extension.umn.edu/event/keystone-plants-and-soft-landings-native-bees

Until Next Time, Happy Gardening!

By Robin Trott, University of Minnesota Extension