John Taft

University of Illinois, Urbana-Champaign | UIUC · Illinois Natural History Survey

There have been dramatic changes to forest lands since the end of the last ice age, about 14,000 years before present, when boreal ecosystems were eventually replaced by deciduous forest and grassland. In Illinois at the time of Euro-American Settlement (circa 1820), forest lands, including fire-maintained woodlands and savannas, comprised about 42...

The U.S. Endangered Species Act (ESA) protects over 2,000 species, but no concise, standardized metrics exist for assessing changes in species recovery status. Tracking these changes is crucial to understanding species status, adjusting conservation strategies, and assessing the performance of the ESA. We helped develop and test novel metrics that...

Climate change is a major environmental challenge that is likely to affect many aspects of life in Illinois, ranging from human and environmental health to the economy. Illinois is already experiencing impacts from the changing climate and, as climate change progresses and temperatures continue to rise, these impacts are expected to increase over t...

Background Vegetation structure, species diversity, and composition have been monitored at a fire-treatment and a fire-free control unit of a dry oak barrens and woodland complex in southern Illinois, USA, over a 29-year period and five burns. The restoration hypothesis is that fire management would result in different trends for vegetation paramet...

This study examines a 65-ha botanically rich grassland mosaic with extensive woody encroachment to determine whether prairie habitat can be restored over a six-year period post treatment. A stratified sample design was utilized for vegetation monitoring. Two vegetation types, Prairie and Old Field, were identified from baseline differences in speci...

Leafhoppers and related Auchenorrhynchous Hemiptera (AH) are among the most diverse grassland herbivores, and many have been linked inexorably to grassland vegetation through diet and shelter for millions of years. Are AH–plant communities in natural grasslands tightly integrated, how does the interaction differ across major ecological gradients, a...

To evaluate the floristic sustainability of three small, isolated tallgrass prairie remnants, spatial and temporal patterns of species and functional group (FG) composition, richness, diversity, and dominance were examined to determine whether there was divergence between edge (outer 10 m) and interior zones. These remnants, all protected and manag...

EXECUTIVE SUMMARY Vegetation monitoring is indispensable for evaluating habitat characteristics and to determine progress with ecological restoration activities. First principles in a monitoring program address goals and how to optimally achieve them with accuracy and precision to facilitate adaptive management. A suggested framework is provided to...

Encroachment of woody species is a significant threat in native grasslands. This study exams the interaction between shrub-sapling overstory and ground layer species and functional group (FG) cover, richness, and diversity along a woody encroachment gradient. The study area is a 65 ha mosaic of tallgrass prairie and shrubland in northeastern Illino...

Violet collinsia (Collinsia violacea) is a winter annual ranging primarily from Missouri to Kansas. An isolated population occurs in central Illinois, 200 km from the nearest Missouri population, in a series of colonies on adjoining river bluffs. Its oak woodland habitat was undergoing vegetation changes consistent with mesophication including esta...

The role of the actinorhizal shrub Ceanothus americanus L. in community organisation of native grasslands was examined in three Illinois tallgrass prairie remnants. We asked can C. americanus structure tallgrass prairie at the patch scale through nitrogen fixation leading to differences in species assemblages and diversity? Expectations were that w...

We propose that patterns of plant functional group occurrences could be a reliable indicator of prairie vegetation quality. A method for assessing tallgrass prairie quality based on density and composition of plant functional groups was developed and tested by comparison with qualitative indices calculated from species data at 17 prairies in Illino...

What species and traits signal vegetation types along prominent environmental gradients in the Central Tien Shan and what are the corresponding diversity patterns? Vegetation was sampled at 41 sites throughout the Kyrgyz Republic using quadrats stratified throughout a 1,000-m2 sample area. Relationships among major environmental gradients, vegetati...

Illinois Tollway Authority Grant/Contract No: 1-596616-375016-191100 INHS Technical Report Prepared for Illinois Tollway Authority

Background/Question/Methods Vegetation changes underway in oak woodland and savanna-like communities in the midwestern United States include increased tree density (thicketization) and shading and loss of diversity in the ground layer. These changes are primarily a result of reduced fire frequency. In the prairie-forest transition zone centered ar...

Fire effects on structure, composition, and species diversity in canopy, shrub/sapling, and ground-cover strata were examined following three burns over an eight-year period in a small (6 ha), isolated flatwoods remnant in south-central Illinois. Prior to fire treatments, size-class distribution patterns for trees indicated two species groups, one...

OBJECTIVES What are the major vegetation types that have occurred in Illinois and how have they changed since the last ice age and more specifically since European-Americans settled the region? Ecological factors influencing trends, composition, and diversity in prairie, savanna, open woodland, and forest communities are examined. Historical and co...

OBJECTIVES What defines a wetland and how have wetlands changed in Illinois? What are the ecological and taxonomic characteristics of wetland plants? This chapter reviews wetlands ecology and trends since European-American settlement.

Vegetation changes underway in oak woodland and savanna communities in the eastern and midwestern United States, primarily a result of reduced fire frequency or fire absence, include increased tree density and shading and loss of species diversity in the ground layer. However, some habitats, particularly on dry-mesic to xeric sites, retain consider...

The Nature Conservancy Grant/Contract No: 1-557324-375013-191100 INHS Technical Report Prepared for The Nature Conservancy

Indices are needed in habitat conservation and restoration to provide repeatable measures relevant to conservation goals. A monitoring and research program was established at Nachusa Grasslands in north-central Illinois (USA) to assess progress in tallgrass prairie restoration and reconstruction efforts and evaluate the effectiveness of indices use...

Fire effects on canopy, shrub/sapling, and ground-cover species composition, structure, and diversity patterns were examined following two burns in a dry sandstone barrens remnant in southern Illinois. Vegetation was monitored at a fire treatment site and a nearby fire-free control site for three years following the first fire and two years followi...

Vegetation at two dry sandstone barrens in Pope County, Illinois was sampled to provide baseline data on composition, structure, diversity, and species-abundance patterns for comparison with vegetational changes resulting from applications of prescribed fire. Permanent plots were established at both sites. Data were collected from canopy, subcanopy...

ID: 8919; issued September 7, 2001 INHS Technical Report prepared for Southwestern Illinois RC & D

Floristic Quality Assessment (FQA) is proposed as a method to assess floristic integrity in Illinois. For the application of FQA, each taxon in the Illinois vascular flora was assigned an integer from 0 to 10 termed a coefficient of conservatism (C). Two basic ecological tenets that the coefficients represent are that plant species differ in their...

Vegetation maps including the upper Midwest generally show two basic vegetation formations: prairie and forest (Vestal 1936, Shelford 1963, Anderson 1970, Iverson et al. 1991). The sharp dividing boundaries implied are more a matter of convenience of scale and difficulties in mapping variable boundaries than a reflection of reality. Of course, the...

issued December 27, 1996 Report issued on: December 27, 1996 INHS Technical Report prepared for Illinois Department of Transportation, Bureau of Environment

. Midwestern flatwoods are open woodlands of level uplands and terraces that occur on impervious subsoil horizons and have seasonally wet and dry soils. Vegetation and soil data from six flatwoods remnants on the Illinoian till plain in Illinois were examined to identify what biotic and edaphic factors control vegetation structure, composition and...

ID: 8730; issued May 1, 1995 INHS Technical Report prepared for Illinois Dept. of Transportation, Bureau of Design and Environment

The vascular flora of the wetland and graminoid plant communities

The horned oak gall forms on twigs of Quercus palustris Muench. and is initiated when the wasp Callirhytis corrigera O.S. oviposits into the periderm or cortex of the twigs. Injury to phellogen as a consequence of oviposition results in dedifferentiation of phelloderm and underlying phloem tissue to form a wound-response phellogen. The wound-respon...

ID: 8333 INHS Technical Report prepared for Nature Conservancy

ID: 8699; issued December 16, 1994 INHS Technical Report prepared for Illinois Department of Transportation

Report issued on: May 1, 2006 INHS Technical Report prepared for Illinois Department of Natural Resources

Monitoring of plant communities is critical for identifying trends and assessing the impact of management. Current methods of ecological monitoring typically involve collection of species-level data and expertise in plant identification, procedures that can be time-consuming and costly. Because many agencies rely largely on volunteer labor, a rapid...

Galls were collected from locations in southern Illinois. Cf. leaf [19]. Thesis (M.S.)--Southern Illinois University at Carbondale, 1982. Vita. Includes bibliographical references (leaves [62]-64).