Progress in succession in the Pennington grove of Pinus virginiana

In 1932 the senior author reported on an ecological survey in stands of Pinus virginiana in Munroe County, Indiana, viz. the Pennington grove near Weimer Lake, two miles sw. of Bloomington, on highway 45, and the Christie-Freeman groves, four miles nw. of Ellettsville. At the time of the 1931 survey very little ground cover had developed in either of these groves. The repesent study considered only the Pennington grove. This stand has seen no decided cultural modifications since the 1931 survey. Periodic surveys were made in the stand by various groups of ecology students of Butler University. These surveys showed a definite trend in succession which now definitely forecasts replacement of the 100 per cent coverage of crown by Pinus virginiana. The invaders consist of a large number of broadleaved species. The forst floor, which in 1931 was almost bare, is today extensively covered by herbs and the seedlings of tree and shrub species. The authors made a survey in July and September of 1947 to define in quantitative terms the trends in succession in the Pennington grove

The Forest Primeval of Indiana as Recorded in the Original U.S. Land Surveys and an Evaluation of Previous Interpretations of Indiana Vegatation

Between 1799 and 1846, the territory which now comprises the State of Indiana was divided by the United States public land survey into six-mile-square townships as a prerequisite for the equitable distribution of public lands. Each township, in turn, was subdivided into 36 sections one-mile square. Section and quarter-section corners, as well as a number of intermediate points, were marked by blazing trees. The location, name, and diameter of more than 214,500 witness trees, composed of more than 80 species and generic groups, were recorded in the Indiana surveyors\u27 journals. These journals and the maps compiled from them, records inscribed before a tidal wave of settlers swept away much of the natural vegetation of the State, represent our most tangible account of Indiana\u27s primeval forests. They are the source of data for this study

Pollen study of five bogs in Price and Sawyer counties, Wisconsin

The problem was to trace vegetational succession in Wisconsin along a given latitude, and specifically to discover whether Quercus became more important in the forest associations towards the western part of Wisconsin than it was in Vilas county and. in adjacent Gogebic county, Michigan

A pollen study in the tension zone of lower Michigan

A transition zone between two large vegetation cover types always presents a tantalizing aspect of vegetational characteristics, frequently suggesting instability. In such areas the microclimate of edaphic factors favors first one and then another group of species which are characteristic components of one of the other of the flanking formations, or smaller fluctuations in temperature and moisture find expression vegetational changes which will not be evident within the boundaries of the definitely expressed formations. This is emphasized boldly by disjunct distribution or intermingling of species of these flanking climaxes, where habitat exerts selective action far greater than is possible under optimum climax control; this may at times even dim the real climax status. As Dachnowski (3) points out, pollen profiles can here, perhaps, give the most reliable picture of the climatically flavored vegetation. It is, therefore, also logical to expect that small variations, or fluctuations, in climate ought to be recorded first in such tension areas by minor changes in vegetation, especially by variation in degree of importance of certain genera in the association complex

A Quarter Century of Botany at Butler University

Kingdoms, inventions, masterpieces in literature, art, music, and architecture are born out of dreams. They may seem flimsy and elusive but they show the things which are closest to the heart far down the lapse of time. For, building along the lines of dreams makes realities.The Butler Botany Department was once upon a time just such an elusive, tantalizingly uncertain dream of a young Ph. D., a dream which occupied his mind when the ink had barely dried on the signatures to his diploma which the University of Michigan had presented to him as tangible evidence of years of intensive preparation for the teaching profession in the field of botany

Pollen frequency of Abies and Picea in peat: A correction on some published records from Indiana bogs and lakes

An error was introduced in a number of reports on pollen profiles from Indiana bogs and lakes because Picea and Abies were separated on basis of size as presented in a key by Sears, which included only Picea mariana but not Picea glauca

Post-Algonquin and Post-Nipissing Forest History of Isle Royale, Michigan

Isle Royale, the largest island in our Great Lakes, is located in the northwestern part of Lake Superior, 50 miles nw. of the Keweenaw Peninsula, 20 miles se. of the Canadian mainland, and 19 miles east of Grand Portage, Minnesota. Maximum elevation is 1300 feet, but most of the higher center ridge does not exceed 1,000 feet. Present altitude of Lake Superior is 602 feet

The Pine Barrens of New Jersey: A refugium during Pleistocene Times

In 1943 Potsger and Otto (13) published the first paper on the pollen analyses of New Jersey peat which involved a series of five bogs from northern and northwestern New Jersey. These bogs represented a rather large geographical area, but their message was unusually uniform. One might, therefore, be justified to assume that the study gave a rather trustworthy history of the vegetation of the glaciated part of the state. From a forest constituted almost entirely of Abies, Picea, and Pinus, succession carried dominance to a pronounced Pinus period. This genus contributed as much as 80% of the pollens at these particular foot-levels. In the upper third of the sediment an association of Tsuga dn Quercus depressed Pinus considerably; and in the topmost levels Castanea entered as last invader of the crown cover

The vegetation of Round Island (Straits of Mackinac), Michigan

The vegetation of Round Island was studied briefly during the summers of 1935 and 1936 while an extensive survey was in progress on Mackinac Island