After a harsh winter, the ground is taking its time to thaw, and spring is moving along slowly here in the upper Midwest. Wildflowers are few and far between in the backyard, except in fenced locations like the Eloise Butler Wildflower Garden in Minneapolis where deer are excluded. On a recent visit, a few woodland wildflower species were beginning to bloom, and leaves of other species (like skunk cabbage and marsh marigold) were just developing.
Bloodroot stems pushed through the thick layer of leaf litter to open their single bright white flowers.
Bloodroot is one of the first to bloom in the moist hardwood forest. Breaking the stem releases an orange-red juice that the native Americans used for war paint and dye.
Hepatica, named for the resemblance of its lobed leaves to the shape of the human liver, is another early bloomer in the woodland garden.
Because its leaves resemble a liver apparently made early herbalists think it was good for liver disorders. Not true, but its astringent properties are useful in treating wounds. A healthy crop of flowers like this would be tasty snack for deer.
Rue anemone was so abundant in the woodland it formed a carpet of small white flowers. It offers only pollen (no nectar) to a variety of bee visitors, but mammals leave it alone because the leaves are unpalatable and toxic.
White Trillium also formed huge clumps that carpeted the forest floor. It is illegal to pick any part of the Trillium plant in MN because doing so will apparently kill the plant.
Their large three-petaled flower and three leaved stem makes it obvious why they are called Trillium. These plants are a little unusual in their close association with ants, which collect the seeds, and in process of storing them, disperse the next generation to a new location.
White trout lilies have nodding heads, with male and female flower parts facing downward. Dense mats of these lilies covered wide expanses of forest floor, so closely packed together that it would be impossible for another type of wildflower to invade. Onondaga Indian women used crushed leaves of this plant for birth control in the spring, so they would not deliver their babies during the harsh winter climate.
Are you noticing a trend here?
The woodland forest floor right now is green, punctuated with a lot of white.
But this woodland looks much different than the typical broadleaf forest where many species of munching herbivores are free to devour these tender plants. In addition, you might have noticed in the first couple of photos that the forest floor has a thick mat of leaves that retain water and add heat to the soil as they decompose. Invasive earthworms haven’t reached this forest yet. However, elsewhere (like my backyard) where the worms thrive in high density, they devour the leaf litter, leaving the soil around trees exposed to erosion and nutrition-poor. Wildflowers can’t grow under these conditions.
Earthworms that accelerate the decomposition of leaf litter leave bare soil around tree roots which then erodes away in spring floods. This is referred to as “forest gingivitis”. Photo from IPM Images. You can read more about the devastating impact of introduced earthworms in one of my earlier blog posts here.