The summer months are a time when our prairies and grasslands come alive with color. In the Cofrin Memorial Arboretum, on the UW—Green Bay campus, a prairie was established by botanist Dr. Keith White and his students in 1974. This demonstration of mesic prairie, where the soils are moderately damp, and dryer oak opening habitats provides students an opportunity to experience these ecosystems firsthand, without having to travel off-campus. It is now a popular walking and biking destination for community members and students who need a break from the stress of classes and work. Our main objective on this prairie is to manage for plant diversity that will support other native species including increasingly rare grassland nesting birds.
If you have a chance to walk the trail through the prairie you will see many unique plant species in flower during the mid-summer. As in all prairies, the plant community in the Keith White Prairie is dominated by a few grass species including Big Bluestem (Andropogon gerardii), Switchgrass (Panicum virgatum), and Indian grass (Sorghastrum nutans). Grasses are wind pollinated and so do not typically have large showy flowers. Instead, grasses have small inflorescences on spikes that become showier in the late summer and fall as the seeds mature.
The colorful jewels of the prairie are the forbs or showy flowering plants. These plants produce flowers that attract insect or hummingbird pollinators and are often showy and colorful. Flowers in the prairie are primarily yellows and purples, which attract insects like bees and butterflies. The most common tall plants you will see in flower in mid-July through August include Compass Plant (Silphium laciniatum), Prairie Dock (Silphium terebinthinaceum), Rosinweed (Silphium integrifolium), many species of Goldenrods (Solidago Spp.), Black-eyed Susan (Rudbeckia hirta), Purple Coneflower (Echinacea purpurea), Rattlesnake Master (Eryngium yuccifolium), Culver’s Root (Veronicastrum virginicum), Yellow Coneflower (Ratibida pinnata), and Wild Bergamot (Monarda fistulosa).
When the prairie was planted, careful consideration was made to match different plants to their preferred soil conditions (e.g. water moisture, productivity). As a result, the numbers and types of flowers vary in different parts of the prairie, even from year to year, in response to weather conditions. A careful observer will be rewarded with a display of flowers that bloom below the grasses and tall forbs. Some of the species to look for are Purple Prairie Clover (Dalea purpurea) and White Prairie Clover (Dalea candida), which are adapted to dry soils; and Bush Clover (Lespedeza capitata), Spotted Bee Balm (Monarda punctata), and Nodding Pink Onion (Allium cernuum), which are adapted to mesic (moderately damp) soils.
The Keith White Prairie is alive with color in the summer and fall and is always a great place to walk. You never know what plants or animals you might see.