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Weather And Plant-Development Data As Determinants Of Grazing Periods On Mountain Range, David F. Costello, Raymond Price May 1939

Weather And Plant-Development Data As Determinants Of Grazing Periods On Mountain Range, David F. Costello, Raymond Price

Aspen Bibliography

Fundamental in economical range-resource management is the determination of proper grazing periods. It is of prime importance to be able to establish a date in the spring when the range has produced sufficient feed to keep livestock in thrifty condition, when it is reasonably safe from excessive trampling and packing of the soil, and when the more important key forage plants have attained sufficient development to withstand grazing use. Such opening dates, as well as the time to defer and rotate grazing and to remove livestock from the range, are dependent in part on the prevailing weather conditions and on …


Staining Techniques In The Study Of The Blood, Donald E. Winnik May 1939

Staining Techniques In The Study Of The Blood, Donald E. Winnik

Bachelors’ Theses

Since the invention of the microscope, the study of the blood and its constituents has been a major interests of histologists and hematologists. The vast amount of material written about the subject could not have been accomplished without the development and use of staining techniques which made possible a more precise observation of the nature of the blood. At the present time there are many procedures and stains which vary greatly in their application and use. It is the purpose of this thesis to review these many methods and catalogue them according to their application in the blood techniques.


A Cytological Study Of The Central Body In Oscillatoria Formosa And Oscillatoria Limosa, Ruth Joanna Dornfeld May 1939

A Cytological Study Of The Central Body In Oscillatoria Formosa And Oscillatoria Limosa, Ruth Joanna Dornfeld

Bachelors’ Theses

No abstract provided.


The Ecology Of Agropyron Inerme On Protected And Heavily Grazed Range Land In Cache Valley, Utah, Wallace R. Hanson May 1939

The Ecology Of Agropyron Inerme On Protected And Heavily Grazed Range Land In Cache Valley, Utah, Wallace R. Hanson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

During the past decade much attention has been attracted to the great range lands of the West. The inherently low productivity of these arid lands coupled with abnormal drought and constantly heavy use by livestock because of lack of grazing control, have caused these lands to become greatly depleted over most of the West. That the vegetation on most range land in the intermountain states is depleted appreciably is evident to the careful observer. Undoubtedly the vegetation of much of the range has decreased in quantity, but more serious in many cases is the decrease in quality. Valuable forage species …


A Taxonomic And Ecological Study Of Acridinae Of Utah (Orthoptera-Locustidae), Herald C. Bennion May 1939

A Taxonomic And Ecological Study Of Acridinae Of Utah (Orthoptera-Locustidae), Herald C. Bennion

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Orthoptera, especially the family Locustidae, is one of the most important and most interesting orders of insects in the state of Utah. It includes a polyphagus group of great economic importance in the state. The topography and climate of Utah varies from forested alpine slopes to hot arid desert wastes, several life zones being represented. This great variation from desert to alpine in Utah presents a rather unique region for taxonomic and ecological studies of the Orthoptera.

The most familiar representatives of the insect order Orthoptera are the long-horned grasshoppers, locusts, crickets, katydids, and cockroaches. Orthoptera are characterized by Comstock …


A Study Of The Sage Grouse (Centrocercus Urophasianus), With Special Reference To Life History, Habitat Requirements, And Numbers And Distribution, Lynn A. Griner May 1939

A Study Of The Sage Grouse (Centrocercus Urophasianus), With Special Reference To Life History, Habitat Requirements, And Numbers And Distribution, Lynn A. Griner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The sage grouse or sage hen Centrocercus urophasianus (Bonaparte) was formerly the most important upland native game bird of the Western States, but has steadily been declining in numbers over most of its range in recent years. This reduction in numbers has aroused the interest of the conservationists of the nation, who, for the past decade or more, have been proposing that something be done for this game species. In recent years along with this interest of the conservationists, there has been an increasing local interest among the sportsmen of the West, with the result that several groups have become …


A Study Of Hybrids Between Sugar Beets And Mangel Wurzels With Reference To Color Factors And Sugar Content, Boyd Berrey May 1939

A Study Of Hybrids Between Sugar Beets And Mangel Wurzels With Reference To Color Factors And Sugar Content, Boyd Berrey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Preliminary unpublished work at the Salt Lake City Laboratory of the Division of Sugar Plant Investigations, Bureau of Plant Industry, United States Department of Agriculture, indicates that beets showing the Y color factor (9) were larger than sugar-beet types recessive for this color factor (y y). It was suggested to the writer that an investigation be made to determine whether or not yield and sugar content were correlated with color factors in beets. Linkages between the R and Y color factors have been reported by Keller (9), and the results indicate a close linkage between color factors R …


Amount Of Underground Plant Materials In Different Grassland Climates, S. B. Shively, J. E. Weaver May 1939

Amount Of Underground Plant Materials In Different Grassland Climates, S. B. Shively, J. E. Weaver

Department of Agronomy and Horticulture: Faculty Publications

From the highlands of central Mexico entirely across the United States and northward into Canada extends the great midcontinental area of grassland. From this central mass, prairie extends westward across Wyoming into eastern Utah, and southwestward through northern New Mexico into northern Arizona. Other grasslands in the northwest cover most of southern Idaho, a part of northern Utah, large areas in eastern Oregon and Washington, and recur in British Columbia. The Pacific prairie occupies the Great Valley of California, and the Desert Plains grassland much of southern Arizona and New Mexico and southwestern Texas. Together they constitute the Grassland or …


The Ecology Of Agropyron Inerme On Protected And Heavily Grazed Range Land In Cache Valley, Utah, Wallace R. Hanson May 1939

The Ecology Of Agropyron Inerme On Protected And Heavily Grazed Range Land In Cache Valley, Utah, Wallace R. Hanson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

During the past decade much attention has been attracted to the great range lands of the West. The inherently low productivity of these arid lands coupled with abnormal drought and constantly heavy use by livestock because of lack of grazing control, have caused these lands to become greatly depleted over most of the West. That the vegetation on most range land in the intermountain states is depleted appreciably is evident to the careful observer. Undoubtedly the vegetation of much of the range has decreased in quantity, but more serious in many cases is the decrease in quality. Valuable forage species …


The Rise And Development Of The Megagametophyte In Yucca Angustissima Engelmann, Antone W. Nisson May 1939

The Rise And Development Of The Megagametophyte In Yucca Angustissima Engelmann, Antone W. Nisson

Theses and Dissertations

The studies involved in this investigation are based upon data and materials secured in the sandy areas of Washington and Iron Counties in southern Utah. The regions in which Yucca angustissima is found have a scant vegetation, are dry, sandy to sandy loam, well-drained, and with an elevation of from 2500 to 5000 feet. Watkins (1937) worked out a very extensive report of the megagametophyte development of Yucca rupicola. He begins with the four megaspore stage, and shows next the disintegration of the three micropylar megaspores. He reported that the chalazal megaspore forms eight free nuclei, by three successive divisions, …


Trichomoniasis Of The Utah Agricultural Experiment Station Dairy Herd, Rue Jensen May 1939

Trichomoniasis Of The Utah Agricultural Experiment Station Dairy Herd, Rue Jensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Bovine trichomoniasis is a venereal infection that reduces the fecundity of cattle. It is caused by Trichomonas foetus (Riedmuller), a flagellated protozoan which inhabits the genital tract, causing inflammation and partial sterility. Both sexes are susceptible to infection. In females it is usually of short duration and frequently terminates spontaneously following abortion. In males the disease has both acute and chronic stages. During the acute stage the prepucial membranes become inflamed and a muco-purulent discharge develops in which trichomonads are abundant. In the following chronic stage symptoms disappear, but the animal remains a carrier and is a dangerous source of …


Front Matter Apr 1939

Front Matter

Journal of the Minnesota Academy of Science

No abstract provided.


Fifty-Third Annual Meeting Of The Iowa Academy Of Science And The Eighth Annual Convention Of The Junior Academy Of Science Of Iowa, April 21 And 22, 1939, Iowa Academy Of Science Apr 1939

Fifty-Third Annual Meeting Of The Iowa Academy Of Science And The Eighth Annual Convention Of The Junior Academy Of Science Of Iowa, April 21 And 22, 1939, Iowa Academy Of Science

Iowa Academy of Science Documents

No abstract provided.


A List Of Birds Observed On The 1938 Semple Expedition To Northeastern México, George M. Sutton, Thomas D. Burleigh Apr 1939

A List Of Birds Observed On The 1938 Semple Expedition To Northeastern México, George M. Sutton, Thomas D. Burleigh

Occasional Papers of the Museum of Natural Science, Louisiana State University

No abstract provided.


The Importance Of Local Mosquito Surveys In Minnesota, William A. Riley Apr 1939

The Importance Of Local Mosquito Surveys In Minnesota, William A. Riley

Journal of the Minnesota Academy of Science

No abstract provided.


A Peripheral Vascular System As Seen By Means Of A Clark Window In The Ear Of The Rabbit, T. H. Seldon, R. H. Barrett, H. E. Essex Apr 1939

A Peripheral Vascular System As Seen By Means Of A Clark Window In The Ear Of The Rabbit, T. H. Seldon, R. H. Barrett, H. E. Essex

Journal of the Minnesota Academy of Science

No abstract provided.


A Human Hereditary Trait Appearing In Offspring From A Cousin-Marriage, C. P. Oliver Apr 1939

A Human Hereditary Trait Appearing In Offspring From A Cousin-Marriage, C. P. Oliver

Journal of the Minnesota Academy of Science

No abstract provided.


Star-Recessive, A Spontaneous Mutation In Drosophila Melanogaster, Edward B. Lewis Apr 1939

Star-Recessive, A Spontaneous Mutation In Drosophila Melanogaster, Edward B. Lewis

Journal of the Minnesota Academy of Science

No abstract provided.


A Key To Snakes Of Minnesota, Milton D. Thompson Apr 1939

A Key To Snakes Of Minnesota, Milton D. Thompson

Journal of the Minnesota Academy of Science

No abstract provided.


Adrenaline, Insulin, Potassium, And Phosphorus In Carbohydrate Metabolism, J. Clifford Stickney Apr 1939

Adrenaline, Insulin, Potassium, And Phosphorus In Carbohydrate Metabolism, J. Clifford Stickney

Journal of the Minnesota Academy of Science

No abstract provided.


A Contribution To The Knowledge Of The Minnesota Flora, John W. Moore Apr 1939

A Contribution To The Knowledge Of The Minnesota Flora, John W. Moore

Journal of the Minnesota Academy of Science

No abstract provided.


Growth Substances And Nutrition Of Protozoa, Alfred M. Elliott Apr 1939

Growth Substances And Nutrition Of Protozoa, Alfred M. Elliott

Journal of the Minnesota Academy of Science

No abstract provided.


Light And Pituitary Activity In The Bird, Adolph R. Ringoen Apr 1939

Light And Pituitary Activity In The Bird, Adolph R. Ringoen

Journal of the Minnesota Academy of Science

No abstract provided.


Kentucky Warbler (Vol. 15, No. 2), Kentucky Library Research Collections Apr 1939

Kentucky Warbler (Vol. 15, No. 2), Kentucky Library Research Collections

The Kentucky Warbler

No abstract provided.


North And South Dakota Horticulture, April 1939, North And South Dakota State Horticultural Societies Apr 1939

North And South Dakota Horticulture, April 1939, North And South Dakota State Horticultural Societies

North and South Dakota Horticulture

Volume 12, Number 4

The Vesper Sparrow, O.A. Stevens
Newslants, H.A. Graves
Nature Department, H.L. Hopkins
President's Corner, H.E. Beebe
Fruit and Vegetable Notes, F.X. Wallner
Manitoba News Letter, W.R. Leslie
Secretary's Corner, W.A. Simmons
Book Review, Mrs. F. Briley
Tomato Growing, R.H. Seydel
Horticultural Travelogue, A.L. Truax
Snow Bound, W.E.H. Porter
News Notes, C.B. Waldron


The Effects Of Stinking Smut (Bunt) And Seed Treatment Upon The Yield Of Winter Wheat, T. A. Kiesselbach, W. E. Lyness Apr 1939

The Effects Of Stinking Smut (Bunt) And Seed Treatment Upon The Yield Of Winter Wheat, T. A. Kiesselbach, W. E. Lyness

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The depreciating effects of bunt or stinking smut (Tilletia levis Kuhn and tritici [Bjerk.] Wint.) upon the yield and quality of winter wheat in Nebraska and many other states are well known. The practical control of this disease through seed treatment has also been established and is being extensively practiced by growers. At the time these experiments were initiated in 1923, formaldehyde was the most commonly used disinfectant, while copper carbonate was just gaining recognition following its introduction by Darnell-Smith in 1915. It has been the chief purpose of the investigations herein reported to study the relative merits of …


The Role Of Forest Fires In The Reproduction Of Black Spruce, R. K. Lebarron Apr 1939

The Role Of Forest Fires In The Reproduction Of Black Spruce, R. K. Lebarron

Journal of the Minnesota Academy of Science

No abstract provided.


The Cellular Changes Induced In The Testes Of The Albino Rat By Artificial Cryptorchidism And X-Radiation, Arthur J. Gatz Apr 1939

The Cellular Changes Induced In The Testes Of The Albino Rat By Artificial Cryptorchidism And X-Radiation, Arthur J. Gatz

Journal of the Minnesota Academy of Science

No abstract provided.


The Rhamnales Of Wisconsin: A Taxonomic Study, Richard W. Pohl Apr 1939

The Rhamnales Of Wisconsin: A Taxonomic Study, Richard W. Pohl

Bachelors’ Theses

The extensive taxonomic literature on the North American Vites was reviewed by L.H. Bailey (3) in 1934. Among the earlier writers, Major John Le Conte published "An Enumeration of the Vines of North America" (32) in the Proceedings of the Academy of Natural Sciences of Philadelphia for 1852-1853. Dr. George Engelmann of St. Louis published a short review of the North American grapes in the American Naturalist for August,1868. He mentioned ten species, giving formal descriptions for none, and commented upon the work of Rafinesque, who had attempted to describe the North American species of Vitis about fifty years previously, …


Effects Of Frequent Clipping On The Underground Food Reserves Of Certain Prairie Grasses, F. S. Bukey, J. E. Weaver Apr 1939

Effects Of Frequent Clipping On The Underground Food Reserves Of Certain Prairie Grasses, F. S. Bukey, J. E. Weaver

Department of Agronomy and Horticulture: Faculty Publications

A series of experiments in which true-prairie grasses were clipped at frequent intervals afforded excellent materials for a study of the effects of such treatment upon the food reserves. Two species of Andropogon, at present the most important dominants of true prairie, were employed. A series of quadrats on a north-facing slope in the Blemont prairie in Lincoln, Nebraska, in which little bluestem Andropogon scoparius, grew in about 70 of big bluestem, A. furcatus, were obtained about a mile distant from virgin lowland prairie near the flood plain of salt creek.