Get to Nerstrand Big Woods for spring bloom

Illustrations by Eddie Thomas eddie.thomas@startribune.com

The staccato drumming of a woodpecker interrupts an otherwise quiet hike through Nerstrand Big Woods State Park about 20 miles south of Northfield.

It's followed by the lilting call of a chickadee, but my eyes barely glance overhead before they're riveted once again on the leaf-littered forest floor where vibrant carpets of lacy moss grow on old logs and shady sides of maple, basswood and oak trees. Seven species of ferns unfurl fiddleheads and low-to-the-ground fronds that create loops like a Quidditch course for Tinkerbell.

The birds are lovely, the greenery's lush, but face it — most spring hikers come for the flowers.

One in particular, the Minnesota dwarf trout lily, draws people from around the country to see the federally protected plant that only grows in three counties of Minnesota and nowhere else in the world, said Elaine Feikema, who has been the park's manager for about 10 years.

Blink, and you might miss it. Its bud is as tiny as a grain of rice, and the flower opens to the size of a dime and stays tucked away below its leaves. It may bloom for six days or up to two weeks if Mother Nature is kind and gentle.

A trail camera marked the flower's location last spring, but staff discontinued that experience because the flower was too small to trigger motion-activated cameras. Its location still is marked conveniently along the trail, which makes it easier for visitors to find the rare flower. It's also a good reminder to stay on the trail to avoid trampling vulnerable plants.

"They have to do all their work before there's a full tree canopy. That's their life cycle," Feikema said.

Park naturalists are available on weekends from April 25-26 through May 16-17 to help the many visitors find and identify a variety of spring flowers.

"It's pretty common to get 200 to 400 people a day [during the spring]," she said. "People discover us every year and see the beauty we have not far from the [Twin] Cities."

Spring ephemerals, as they're called, tend to bloom in waves that can start as early as late March or not until late April if winter is stubborn about leaving. Among the first to pop up are the fuzzy-stalked blooms of hepatica, white-petaled bloodroot, Dutchman's breeches (looking like bloomers on a laundry line) and delicately striped pink spring beauty.

Shawn Fritcher, area resource specialist for state parks and trails in southeast Minnesota, enjoys seeing spring's first flowers like hepatica the best, but also loves coming across woods that are blanketed in blooms such as the long-petaled white trout lilies.

Trout lilies bloom in a second wave of flowers that includes anemones, followed by maroon wild ginger, lavender wild phlox and geranium, striped and hooded Jack-in-the-pulpit, and sunny yellow marsh marigolds. Sugar-tipped columbine, trillium, sweet Cicely and showy orchis — a cluster of tiny orchids — come in the last wave of blooms.

With the roving naturalists, field guide kits that visitors can check out (first-come, first-served) and close to 120 species of wildflowers in this pocket of Big Woods habitat, Nerstrand can be ideal for learning about spring blooms and then trying to spot them among southeastern Minnesota's other hardwood forests and state parks.

You can spot most of the blooms without leaving the easy main hike at Nerstrand, which runs about three city blocks and ends at Hidden Falls. It doesn't have the size and roar of North Shore waterfalls, but it's soothing and pretty, and cascades in such a precise line of rock you'd think it was man-made. Look for the moisture-loving marsh marigolds lining its banks.

If you're into birding, keep an eye out for red-headed woodpeckers (a species of special concern), along with migrating warblers and bald eagles. This part of Minnesota has several state parks if you want to continue on a road trip inspired by spring's blooms.

"Do some exploring," Fritcher said. "[The parks] all have neat things to see, no matter where you go."