MICHIGAN BOTANICAL SOCIETY
SOUTHWESTERN CHAPTER FIELD TRIP
Oak Savannas & Associated Prairies
Ft Custer Training Center
Dr. Tyler Bassett
Conservation Scientist - Botanist
Michigan Natural Features Inventory
Saturday June 27, 2026, 10am to noon
Oak Savannas and associated prairies once occurred in a shifting mosaic of upland and wetland plant communities that depended on frequent fire for maintaining open and semi-open conditions. All these communities are now rare or nearly extirpated from Michigan.
Oak Barrens are fire-dependent savannas dominated by oaks, having between 5% and 60% canopy with a wide range of shrub cover above the forb and graminoid ground layer. The flora of savannas was a mixture of prairie and forest species, with prairie forbs and grasses more abundant in open areas and forest forbs and woody species more common in shaded areas. Many of the species of oak savanna were, in fact, savanna specialists that thrived in the mottled light conditions provided by the scattered oak canopy. Characteristic shrubs include serviceberry (Amelanchier spp.), bearberry (Arctostaphylos uva-ursi), New Jersey tea (Ceanothus americanus), sweetfern (Comptonia peregrina), dogwoods, American hazelnut (Corylus americana), beaked hazelnut (C. cornuta), hawthorn species (Crataegus spp.), wintergreen (Gaultheria procumbens), huckleberry (Gaylussacia baccata), wild plum (Prunus americana), choke cherry (P. virginiana), sand cherry (P. pumila), dwarf chinquapin oak (Quercus prinoides), shining sumac (Rhus copallina), pasture rose (Rosa carolina), northern dewberry (Rubus flagellaris), prairie willow (Salix humilis), and low sweet blueberry (Vaccinium angustifolium)
Predominant graminoids included big bluestem (Andropogon gerardii), little bluestem (Schizachyrium scoparium), Indian grass (Sorghastrum nutans) and Pennsylvania sedge (Carex pensylvanica), with Pennsylvania sedge often replacing the bluestems in shaded areas and fire-suppressed communities. Prevalent forbs include hair grass (Avenella flexuosa), false foxglove (Aureolaria spp.), tickseed (Coreopsis lanceolata), slender sand sedge (Cyperus lupulinus), poverty grass (Danthonia spicata), panic grass (Dichanthelium implicatum), flowering spurge (Euphorbia corollata), woodland sunflower (Helianthus divaricatus), porcupine grass (Hesperostipa spartea), June grass (Koeleria macrantha), false dandelion (Krigia biflora), white pea (Lathyrus ochroleucus), hairy bush clover (Lespedeza hirta), rough blazing star (Liatris aspera), dwarf blazing star (L. cylindricea), wild lupine (Lupinus perennis), wild bergamot (Monarda fistulosa), wood betony (Pedicularis canadensis), black oatgrass (Piptochaetium avenaceum), prairie heart-leaved aster (Symphyotrichum oolentangiense), goats-rue (Tephrosia virginiana), and birdfoot violet (Viola pedata).
Mesic sand prairie experience fluctuating water tables, with relatively high-water tables occurring in the spring followed by drought conditions in late summer and fall. Thus, the community contains plants that can tolerate a broad range of moisture conditions but is dominated by upland species. Dominant grasses include little bluestem, big bluestem, and Indian grass. Pennsylvania sedge (Carex pensylvanica) is often important. Low areas transitional to wet-mesic prairie or wet-mesic sand prairie have increased importance of bluejoint grass (Calamagrostis canadensis), cordgrass (Spartina pectinata), sedges (Carex spp.), rushes (Juncus spp.), and bulrushes (Scirpus spp.). Common forbs include colic root (Aletris farinosa), thimbleweed (Anemone cylindrica), spreading dogbane (Apocynum androsaemifolium), arrow-leaved aster (Symphyotrichum urophyllum), tall coreopsis (Coreopsis tripteris), smooth scouring rush (Equisetum laevigatum), flowering spurge (Euphorbia corollata), wild-strawberry (Fragaria virginiana), northern bedstraw (Galium boreale), tall sunflower (Helianthus giganteus), alum root (Heuchera americana), path rush (Juncus tenuis), false dandelion (Krigia biflora), prairie phlox (Phlox pilosa), old-field cinquefoil (Potentilla simplex), black-eyed Susan (Rudbeckia hirta), stiff goldenrod (Solidago rigida), Missouri ironweed (Vernonia missurica), and arrow-leaved violet (Viola sagittata).
The difficulty level is easy. Mosquito repellent and/or netting, sunscreen, water as well as suitable clothing are suggested.
Tyler Bassett is a Botanist and Plant Ecologist with the Michigan Natural Features Inventory. He has 25 years of experience studying the plants and plant communities of the Upper Midwest. His work, in part, aims to document and conserve these species, and to restore, expand, and reconnect the diminishing fragments of habitat that they require for persistence. He holds a B.S. in Biology from Western Michigan University, and a Ph.D. in Plant Biology, and Ecology, Evolutionary Biology, and Behavior from Michigan State University.
REGISTRATION IS REQUIRED: The Ft Custer Training Center is federal property and is used as training facility by the Michigan National Guard and other branches of the armed forces. Access to the Training Center is restricted and everyone must register in advance on or before Sunday 21jun2026. A list of attendees will be sent to Training Center authorities for review. If you are not on the list, you will not be allowed to enter the Training Center. Please bring a state issued photo ID for entry. Registration is now closed.
Directions: The address for entry gate to the Training Center is 2501 26th St., Battle Creek, MI. From the Kalamazoo area, take Gull Road (M-343) at the traffic circle turn right (east) onto E G Ave. In 7.1 miles, turn left (east) onto M-96. In 3.5 miles, turn right (south) onto Armstrong/Denso Road. In 1.0 mile the entry gate is on your right (south). The coordinates are 42.3299637934549, -85.28907654261846