William E. McClain

Fire impact on groundlayer flora in a sand forest 1990-1994.

-Groundlayer response to prescribed fire was monitored in a central Illinois sand forest between 1990 and 1994. The first of three annual fires resulted in a significant increase in richness and cover of herbaceous species, and a minor decrease in woody cover. Successive fires maintained or slightly increased herb richness and cover, but did not change woody cover. Before burning, the forest understory was dominated by dense shrubs (7489% cover) over a sparse herb layer (4-18% cover). After the first fire, herb cover increased over fourfold to 48-57%, and to 65-66% after the second fire. Fire nonsignificantly reduced woody cover by some 20%, primarily due to a reduction in Parthenocissus quinquefolia (Virginia creeper), but did not affect frequency of woody vegetation. Species richness increased over 50% after the first fire, from 6.2-7.0/M2 to 9.8-10.8/M2, due to the increased frequency of herbaceous, and especially annual, species. Most of the postfire increase in herbaceous cover was due to Eupatorium rugosum (white snakeroot), which increased from 3X higher than preburn levels. The alien biennial Alliaria petiolata was maintained in a reduced condition by repeated fires, but in the absence of fire doubled in cover every 2 yr, from 4.6% in 1990 to 8.6% in 1992 to 17.0% in 1994.

Fire History of a Post Oak (Quercus stellata Wang.) Woodland in Hamilton County, Illinois

Abstract Cross-sections of 36 post oaks (Quercus stellata Wang.) were examined to determine the fire history of a post oak woodland in Hamilton County, Illinois. The 226-year tree ring record contained three distinct periods; a fire era from 1776 to1850 having a mean fire return interval of 1.97 years, a fire-free period from 1851 to1884, and a second fire era from 1885 to 1996 having a mean fire return interval of 1.44 years. The fire-free interval corresponds with the rapid settlement of Hamilton County during 1850–85. The fires between 1770 and 1850 are considered landscape fires associated with Native Americans and/or early European settlers, while those between 1885 and 1996 are thought to be due to burning of local woodlands, a practice that became increasingly less common in the late 20th century. Three post oak cohorts were identified, including 211–224 year-old (217-year mean), 137–151 year-old (144-year mean), and 104–115 year-old (105-year mean) age classes. Post oak recruitment ended and fire sensitive hickories (Carya ovata and C. tomentosa), black cherry (Prunus serotina), sassafras (Sassafras albidum), and black oak (Quercus velutina) now dominate the seedling and sapling layers of the woodland.

Floristic Assessment of the Henry Allan Gleason Nature Preserve, Mason County, Illinois

Abstract The Henry Allan Gleason Nature Preserve is located in the extensive glacial sand deposits associated with the Illinois River in central Illinois. An extensive sand dune is present within the preserve on which undisturbed dry sand prairie, disturbed dry sand prairie, and blow-out communities are present. The undisturbed sand prairie is dominated by Schizachyrium scoparium (42% of the importance value [IV]), along with Tephrosia virginiana, Opuntia humifusa, and Ambrosia psilostachya. The disturbed sand prairie is dominated by Eragrostis trichodes (24% of the IV), followed by Heterotheca camporum, Ambrosia psilostachya, and Rhus aromatica. Common species in an active blow-out includes Aristida tuberculosa and Cyperus grayioides, while nearly stabilized blow-outs have a high diversity characterized by Bouteloua hirsuta, Ambrosia psilostachya, and Eragrostis trichodes. A total of 172 plant species were found: 4 fern and fern-allies, 3 gymnosperms, 39 monocots, 126 dicots. Thirty-one non-native species were found, comprising about 18% of the flora. The Floristic Quality Index for the nature preserve is 41.33 when the non-native species are included in the calculations.

Floristic Study of Sand Prairie-Scrub Oak Nature Preserve, Mason County, Illinois

ABSTRACT The 590 ha Sand Prairie-Scrub Oak Nature Preserve in Mason County, Illinois contains remnant dry sand prairies, sand savanna, sand forest, and successional fields. Purchased in 1969, the abandoned agricultural fields have been allowed to re-vegetate naturally. The vegetation of a mature dry sand prairie was compared with two successional fields, one 60- and one 30-years-old. The mature dry sand prairie was dominated by Schizachyrium scoparium (little bluestem), Dichanthelium villosissimum (hairy panic grass), Tephrosia virginiana (goats-rue), Ambrosia psilostachya (western ragweed), and Opuntia humifusa (common pricklypear). Eragrostis trichodes (sand love grass) dominated the 60-year-old successional fields. The 30-year-old successional field was dominated by Eragrostis trichodes, Strophostyles helvula (wild bean), and Monarda punctata (horsemint). A total of 393 vascular plant species were documented for the preserve.

Sand prairie communities of Matanzas nature preserve, Mason County, Illinois

ABSTRACT The Matanzas Prairie Nature Preserve is located near Bath, Mason County, Illinois, in the extensive glacial sand deposits associated with the Illinois River. This Preserve contains the only remaining high quality wet-mesic sand prairie, shrub prairie, and sedge meadow associated with the Illinois River sand deposits. The sedge meadow, about 5 ha in size, was dominated by Carex stricta (Importance Value or IV of 66.6 out of 200), Calamagrostis canadensis, and Rosa palustris (both with IVs of 28.3). The wet-mesic sand prairie occurred on slightly higher ground and was dominated by Solidago canadensis (IV of 34.2), Andropogon gerardii (IV of 25.9), Carex stricta (IV of 21.9), Poa pratensis (IV of 18.0), and Euthamia graminifolia (IV of 17.7). Parts of the Preserve were shrub prairie with a ground layer similar to the wet-mesic sand prairie community. A total of 340 species of vascular plants were encountered on the Preserve: 5 fern and fern-allies; 100 monocots; and, 235 dicots. Except for Poa pratensis, which was among the dominant species in the wet-mesic sand prairie and shrub prairie, the 38 exotic species were rarely encountered (11% of the flora). The Floristic Quality Index (including exotic species) for the sedge meadow was 38.80, the wet-mesic sand prairie 43.65, and the shrub prairie 31.76.

Vascular Flora and Composition of Miles Hill Prairie, Monroe County, Illinois

ABSTRACT Large expanses of loess hill prairie were once common along the bluffs of the Mississippi and Illinois rivers of Illinois. These communities occur in forest openings on thick loess deposits overlying bedrock and frequently have expanses of exposed limestone at their margins (glades). Warm season, clump-forming grasses dominate the herbaceous vegetation along with a mixture of prairie and open forest species. Miles Hill Prairie, Monroe County, Illinois is located about 20 km west of Waterloo in the Northern Section of the Ozark Natural Division. Within the prairie, 148 vascular plant species were recorded with 40 species found in the survey plots. Schizachyrium scoparium dominated followed by Andropogon gerardii, Solidago speciosa, Sorghastrum nutans, and Bouteloua curtipendula. Common forbs include Pycnanthemum pilosum, Symphotrichum patens, and Symphotrichum oolentangiense with Cornus drummondii the most abundant shrub, and Torilis japonica the only exotic species in plots. This is a high-quality loess hill prairie that is well maintained by prescribed fire and brush removal. Most species encountered were common to loess hill prairies, with the 19 exotic species being rare and mostly restricted to prairie edges.