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An Ecological Study Of Timpanogos Creek From Aspen Grove To Wildwood, Marion L. Harris Jan 1926

An Ecological Study Of Timpanogos Creek From Aspen Grove To Wildwood, Marion L. Harris

Theses and Dissertations

Ecology may be oonsidered as one of the vital parts of botany, since there are two ultimate facts in this science; namely, the plant and its habitat . The habitat is made up of the physical factors that control function. At Timpanogos there are so many different habitats, that the chief problem is not that of finding a problem to study, but rather that of selecting one from the many. The purpose of this paper is to point out some of the interesting features that are found in a study of Timpanogos Creek from Aspen Grove to Wildwood.


Plant Production As A Measure Of Environment: A Study In Crop Ecology, J. E. Weaver Jul 1924

Plant Production As A Measure Of Environment: A Study In Crop Ecology, J. E. Weaver

Department of Agronomy and Horticulture: Faculty Publications

Table of Contents:
Introduction
Location and Description of Stations
Comparisons of Environments
Experimental Methods and Results, 1920
Experiments during 1921
Environmental Conditions
Plant Yield
Experiments during 1922
Environmental Conditions
Native Plant Yield
Growth Of Maize
Summary of Experiments on Native Vegetation
Summary


Range And Pasture Management, J. E. Weaver Apr 1924

Range And Pasture Management, J. E. Weaver

Department of Agronomy and Horticulture: Faculty Publications

Sampson's range and pasture management is an excellent example of the application of the principles of ecology to the solution of economic problems. In grazing experiments it is of equal importance to know what is happening to the stock and to the vegetation. This emphasizes the fact, which ecologists are coming more and more to recognize, that animals, both wild and domesticated, have a proper place in the environment and that they play an important role in modifying the vegetational development. This volume consists largely of first-hand information obtained by the author during fifteen years of intensive pasture investigations for …


Relative Transpiration Of Coniferous And Broad-Leaved Trees In Autumn And Winter, J. E. Weaver, A. Mogensen Dec 1919

Relative Transpiration Of Coniferous And Broad-Leaved Trees In Autumn And Winter, J. E. Weaver, A. Mogensen

Department of Agronomy and Horticulture: Faculty Publications

Transpiration has been of special interest to many investigators for a long time. At first it was considered without reference to environmental factors, but later, as more observations were made and these factors were noted to have a marked effect upon the water loss, they were taken into consideration. Many of the data assembled have been limited to plants during the growing season, so that it has seemed profitable to obtain not only quantitative data on winter losses, but also a comparison of the relative transpiration of conifers and broad-leaved trees in summer and winter.


The Quadrat Method In Teaching Ecology, J. E. Weaver Nov 1918

The Quadrat Method In Teaching Ecology, J. E. Weaver

Department of Agronomy and Horticulture: Faculty Publications

The quadrat method of studying vegetation has become an integral part of many of the more important ecological investigations. Although occasionally used throughout the past century for determining the amount of plant material produced or for purposes of enumeration, it was organized into a definite system for the study of the structure and development of vegetation by Pound and Clements (15, 16) and Clements (2, 3, 5) only about eighteen years ago. Since that time it has been used, sometimes in a modified form (12, 21), by numerous investigators both American and European. Indeed, with the rapid increase in the …


Further Studies In The Ecotone Between Prairie And Woodland, R. J. Pool, J. E. Weaver, F. C. Jean Jan 1918

Further Studies In The Ecotone Between Prairie And Woodland, R. J. Pool, J. E. Weaver, F. C. Jean

University Studies (University of Nebraska) (1888–1984)

A series of intensive investigations of the ecological features of the tension zone between prairie and woodland in the Mississippi valley was begun by Weaver and Thiel in 1915. These studies were continued for two seasons in Minnesota and were also extended to the prairies of eastern Nebraska in 1916. These investigations represent the first attempt to attack the prairie-forest problem on a comprehensive scale by means of the quantitative methods of modern ecology. Some of the results secured from these studies have been published as the first paper of a series planned to deal with critical investigations in the …


Further Studies In The Ecotone Between Prairie And Woodland, R. J. Pool, J. E. Weaver, F. C. Jean Jan 1918

Further Studies In The Ecotone Between Prairie And Woodland, R. J. Pool, J. E. Weaver, F. C. Jean

Department of Agronomy and Horticulture: Faculty Publications

A series of intensive investigations of the ecological features of the tension zone between prairie and woodland in the Mississippi valley was begun by Weaver and Thiel in 1915. These studies were continued for two seasons in Minnesota and were also extended to the prairies of eastern Nebraska in 1916. These investigations represent the first attempt to attack the prairie-forest problem on a comprehensive scale by means of the quantitative methods of modern ecology. Some of the results secured from these studies have been published as the first paper of a series planned to deal with critical investigations in the …


Ecological Studies In The Tension Zone Between Prairie And Woodland, J. E. Weaver, Albert F. Thiel Apr 1917

Ecological Studies In The Tension Zone Between Prairie And Woodland, J. E. Weaver, Albert F. Thiel

Department of Agronomy and Horticulture: Faculty Publications

Upon the completion of a series of investigations in southeastern Washington and adjacent Idaho, in which there was found to be a direct relation between the available water content of the soil and the evaporating power of the air as succession progressed from grassland through scrub to forest, the senior writer moved to Minneapolis, Minnesota. Here such excellent conditions of prairie invaded by scrub and followed by forest offered themselves for study that the services of the junior author were enlisted and an analysis of the situation attempted. Later this study was supplemented by similar work carried on at Lincoln, …


The Insect Association Of A Local Enviornmental Complex In The Dsitrict Of Holmes Chapel, Cheshire., Alfred E. Cameron Jan 1917

The Insect Association Of A Local Enviornmental Complex In The Dsitrict Of Holmes Chapel, Cheshire., Alfred E. Cameron

Bu

No abstract provided.


The Relation Of Leaf Structure To Physical Factors, Edith Schwartz Clements Jan 1905

The Relation Of Leaf Structure To Physical Factors, Edith Schwartz Clements

School of Biological Sciences: Faculty Publications

The leaf, as the seat of important physiological functions of the plant, and because of its modification by external factors, has long been a fruitful subject for investigation. As a rule, however, investigators have confined themselves solely to the histology and morphology of the leaf, independent of its relations to physical factors. Where the latter have been considered at all, it has been in a more or less general way, or undue importance has been assigned to one or another of the physical factors, and others have been ignored entirely. In no case have they been carefully measured. The aim …