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Hardiness Of Woody Plants In Minnesota, H. E. Stork Apr 1941

Hardiness Of Woody Plants In Minnesota, H. E. Stork

Journal of the Minnesota Academy of Science

No abstract provided.


Native Midwestern Pastures: Their Origin, Composition, And Degeneration, J. E. Weaver, W. W. Hansen Feb 1941

Native Midwestern Pastures: Their Origin, Composition, And Degeneration, J. E. Weaver, W. W. Hansen

Department of Agronomy and Horticulture: Faculty Publications

According to Doctor J. E. Weaver and Mr. W. W. Hansen the purpose of this bulletin is to present certain facts involved in range and pasture management by outlining in some detail the fundamental phenomenon of vegetational change upon which all rational pasture studies must be based. They maintain that the native prairie vegetation is an organic entity in close adjustment with soil and climate, which has developed gradually to its present condition of dynamic stabilization. When the prairie is grazed and trampled, various changes occur, the nature and extent of which vary somewhat directly with the degree of disturbance, …


Embryo And Seedling Development Of Tropaeolum Majus, L., Florence Ann Norris Jun 1940

Embryo And Seedling Development Of Tropaeolum Majus, L., Florence Ann Norris

Bachelors’ Theses

The family Tropaeolacese contains one genus Tropaeolum with about fifty species living on the mountains of Mexico and the Andes as far south as Chile. Three occur also in South Brazil. Tropaeolum majus L. and Tropaeolum minus L., natives of Peru, are the "Nasturtium" of our gardens.


A Historical Study Of The Development Of The Embryo In The Germinating Tubers Of Nephrolepis Cordifolia, Baker, Verne Schwalbach May 1940

A Historical Study Of The Development Of The Embryo In The Germinating Tubers Of Nephrolepis Cordifolia, Baker, Verne Schwalbach

Bachelors’ Theses

The tubers of Nephrolepis cordifolia.- Baker were first reported and studied by Professor Heinricher (1881). His work with the tubers was concerned with what he termed regeneration. However, this term, regeneration, was found to have the same connotation as the term germination and the two were used interchangeably throughout his work.


Longevity Of Red Pine Seed, Eugene I. Roe Apr 1940

Longevity Of Red Pine Seed, Eugene I. Roe

Journal of the Minnesota Academy of Science

No abstract provided.


Noteworthy Plants From The Duluth Area, Olga Lakela Apr 1940

Noteworthy Plants From The Duluth Area, Olga Lakela

Journal of the Minnesota Academy of Science

No abstract provided.


Shrubs For Wildlife On Farms In The Southeast, Verne E. Davison Jan 1940

Shrubs For Wildlife On Farms In The Southeast, Verne E. Davison

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

On many farms in the Southeast patches of briars and small scrubby growth have been allowed to grow up in pastures, fields, and meadows, where they interfere with good farming. Shrubs have therefore come to be thought of all too often as plants that should be destroyed. The areas they occupy are shrubbed out and burned in an attempt to combat insects and to present an appearance of clean farming. This treatment destroys ground cover and hastens erosion. It deprives wildlife of food and shelter. It reduces the number of beneficial insects but does not exterminate the noxious kinds.

Shrubbing …


The Genetics Congress, R. A. Emerson Jan 1940

The Genetics Congress, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

Mice and men reported from

Edinburgh after the Congress

(JOURNAL OF HEREDITY for

September 1939) but since then there

has been silence, as far as getting into the

record any details of the Congress. On

account of the disruption to trans-Atlantic

travel caused by the declaration of

war between England and Germany,

September 3, the American delegation to

the Congress was considerably delayed

in getting back. Only two failed ultimately

to return, Dr. and Mrs. F. W.

Tinney of the Division of Farm Crops

of the University of Wisconsin. They

were among about a dozen members of

the Congress who …


Origin And Development Of Tissues In The Root Of Daucus Carota, L., M. Gerald Vodde Aug 1939

Origin And Development Of Tissues In The Root Of Daucus Carota, L., M. Gerald Vodde

Bachelors’ Theses

When botanists of the seventeenth century began their anatomical investigations of plants, their attention was quite naturally centered on the parts of the plant which they most readily observed growing above the ground. The Englishman, Robert Hooke (1661), revolutionized the botanical sciences when he announced his discovery of the fact that plant tissues are composed of cavities which he called cells. Many workers enthusiastically took up the study of plant tissues and the individual cells of which these tissues are composed. Progress was rather slow, and it was not until approximately two hundred years later that the cell theory was …


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 …


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 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, …


Fifty Years Of Achievement In Agricultural Investigation, R. T. Prescott Mar 1939

Fifty Years Of Achievement In Agricultural Investigation, R. T. Prescott

Nebraska Agricultural Experiment Station: Historical Circulars

In Nebraska, a hustling frontier state in 1887, the legislature hesitated not at all in taking advantage of the provisions of the Hatch Act, and now that fifty years have elapsed since the Station was founded, seventy-five years since the Land Grant College Act was passed and the U. S. Department of Agriculture established, and almost twenty-five years since the Agricultural Extension Service was added, it seems worth while to present a general summary of achievement within the state. The main object will be to show some of the important things that have been learned through the investigations of the …


Bulletin No. 284 - Lygus Bugs In Relation To Alfalfa Seed Production, C. J. Sorenson Jan 1939

Bulletin No. 284 - Lygus Bugs In Relation To Alfalfa Seed Production, C. J. Sorenson

UAES Bulletins

This investigation, which continued during the two succeeding years, had four primary purposes: (1) to determine the distribution of these plant bugs and the intensity of their infestation in the alfalfa-seed districts of the state; (2) to ascertain whether these bugs constitute an important factor, either causing or contributing to, the excessive flower-drop annually occurring in alfalfa-seed fields, or if they are otherwise responsible for decreased yields of alfalfa seed; (3) to study the general biology of these insects with particular reference to their life histories in alfalfa as the host plant; and (4) to investigate possible practical methods for …


Bulletin No. 286 - Some Trends In Utah's Agriculture, Walter U. Fuhriman Jan 1939

Bulletin No. 286 - Some Trends In Utah's Agriculture, Walter U. Fuhriman

UAES Bulletins

During the last two decades agriculture has been subjected to many strains and stresses- social, economic, physical, and biological. Infestations of noxious weeds and insect pests have in some instances necessitated changes in crops grown and in farming practices. Changes in precipitation have induced alternate expansion and contraction of cultivated acreage in certain areas. Improved machinery has reduced the demand for farm labor, caused shifts in crops grown and in farm population. Changes in dietary habits have increased the demand for some farm commodities and decreased the demand for others, while wide fluctuations in farm prices have wrought rapid changes …


A Zygotic Lethal In Chromosome 1 Of Maize And Its Linkage With Neighboring Genes, R. A. Emerson Jan 1939

A Zygotic Lethal In Chromosome 1 Of Maize And Its Linkage With Neighboring Genes, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

A Bolivian maize

maize with mosaic red pericarp and cob, here designated by the symbol M-M, crossed with a local inbred strain of maize having white pericarp and cob, W-W, produced in F1 21 M-M and 28

W-W plants, not far from the I : I relation expected on the assumption that

the M-M parent was heterozygous for pericarp and cob color, M-M/W-W.

In F2 and segregating F3 cultures, however, there were 130 M-M and 64

W-W plants obviously a 2 : I instead of the 3 : I relation expected. Later cultures

increased these records to …


Bulletin No. 282 - Pioneering In Western Agriculture Oct 1938

Bulletin No. 282 - Pioneering In Western Agriculture

UAES Bulletins

A resume of the First Half-Century of Research 1888 - 1938 at the Utah Agricultural Experiment Station including the Biennial Report 1936 - 1938.

The Utah Agricultural Experiment Station in reaching the fiftieth year of its history can look back upon a brilliant record of achievement covering the practical as well as the more fundamental problems of agriculture in this arid state. The difficulties encountered in conquering deserts down through human history have demonstrated the mastery of man's spirit over his physical environment. Man's destiny to multiply, subdue, and replenish the earth cannot be accomplished by enjoying the fruits of …


Bulletin No. 280 - Sinusitis Of Turkeys And Its Treatment, D. E. Madsen Aug 1938

Bulletin No. 280 - Sinusitis Of Turkeys And Its Treatment, D. E. Madsen

UAES Bulletins

Sinusitis has long been recognized as one of the barriers to profitable production of chicken products; and with the growth of commercial turkey production in the west its existence in this bird has become increasingly significant. In Utah areas considerable loss is encountered yearly from this disease in turkeys. This loss has prompted some investigations as to what measures may be adopted for its control.


Some Coccogoneales Common To The Vicinity Of Milwaukee, Joseph John Valenti Jun 1938

Some Coccogoneales Common To The Vicinity Of Milwaukee, Joseph John Valenti

Bachelors’ Theses

The Cyanophyceae, a group of plants which are commonly known as the Blue-Green Algae, have a characteristic blue-green color due to a green pigment-chlorophyl, with which there is associated a blue pigment, phycocyanin. The Cyanophyceae are found everywhere on fresh salt water, on damp soil, rocks, bark, etc. These are among the simplest and lowest of all green plants. The plant consists of a single cell, but in most species these cells tend to adhere in colonies. These algae are able to grow at a higher temperature than can any other algae.


A Proposed Method For Classifying And Evaluating Soils On The Basis Of Productivity And Use Suitabilities, Arthur Anderson, A. P. Nelson, F. A. Hayes, I. D. Wood May 1938

A Proposed Method For Classifying And Evaluating Soils On The Basis Of Productivity And Use Suitabilities, Arthur Anderson, A. P. Nelson, F. A. Hayes, I. D. Wood

Nebraska Agricultural Experiment Station: Historical Research Bulletins

It is the object of this paper to present a method for classifying and evaluating the soils as mapped in regular soil surveys on the basis of land types, which are here defined as areas having reasonably similar productivity and use suitabilities. The standards used to differentiate land types will vary according to the desired objectives, but any material difference in yield, or in practices necessary to maintain a desirable level of productivity will justify recognition of land types. The proposed procedure involves a more detailed study of the influence which soils, slope, erosion, and drainage have on specific crops …


Physiology Of Ethylene Production, Use, And Reactions In Plants, R. C. Nelson Apr 1938

Physiology Of Ethylene Production, Use, And Reactions In Plants, R. C. Nelson

Journal of the Minnesota Academy of Science

No abstract provided.


Effect Of Colchicine On Chromosome Number And Cell Size In Some Horticultural Plants, Catharine Lunt Becker Apr 1938

Effect Of Colchicine On Chromosome Number And Cell Size In Some Horticultural Plants, Catharine Lunt Becker

Journal of the Minnesota Academy of Science

No abstract provided.


Some Higher Fungi In The Vicinity Of Winona, Sister M. Sylvia Apr 1938

Some Higher Fungi In The Vicinity Of Winona, Sister M. Sylvia

Journal of the Minnesota Academy of Science

No abstract provided.


A Survey Of Father John Katzner's Horticultural Work, Adelard Thuente Apr 1938

A Survey Of Father John Katzner's Horticultural Work, Adelard Thuente

Journal of the Minnesota Academy of Science

No abstract provided.


The Chemical Nature And Distribution Of Black Pigment In Soil, William Sherman Gillam Jan 1938

The Chemical Nature And Distribution Of Black Pigment In Soil, William Sherman Gillam

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

As used in this paper, humus refers to that portion of the soil organic matter peptized by four per cent ammonium hydroxide. That fraction peptized by four per cent ammonium hydroxide, precipitated by acids, and insoluble in alcohol, is designated as black pigment. It is called humic soil by many writers.


Root Distribution Of Trees In Relation To Soil Profile, J. E. Weaver Jan 1938

Root Distribution Of Trees In Relation To Soil Profile, J. E. Weaver

Department of Agronomy and Horticulture: Faculty Publications

One of the pronounced trends in American forestry during the past decade has been the development of a widespread interest in soils. As a consequence to the soil as a part of the environmental complex has been attributed much greater importance than formerly in forest production. In fact, the individual horizons of the soil profile are receiving attention each as a more or less distinct habitat of that highly organized body designated as soil. Just as soil scientists, until recent years, have given inadequate attention to the factor of vegetation in the constitution and development of soils, so too little …


The Influence Of Various Soil Factors Upon Potato Scab Caused By Actinomyces Scabies, R. W. Goss Aug 1937

The Influence Of Various Soil Factors Upon Potato Scab Caused By Actinomyces Scabies, R. W. Goss

Nebraska Agricultural Experiment Station: Historical Research Bulletins

Scab, caused by Actinomyces scabies (Thaxt.) Giiss., is a potato disease of major importance in western Nebraska. Seed treatments are effective in controlling seed-borne scab, but it has been shown that even when healthy or treated seed potatoes are used the disease may be very severe because of infection from the soil. Crop rotation will reduce the incidence of the disease, but the fact that potato scab may cause serious loss in soils never before planted to potatoes indicates that there are numerous factors other than the time interval between potato crops which affect the occurrence of the disease. A …


Bulletin No. 277 - A Study Of Utah's Winter Range: Composition Of Forage Plants And Use Of Supplements, A. C. Esplin, J. E. Greaves, L. A. Stoddart Jun 1937

Bulletin No. 277 - A Study Of Utah's Winter Range: Composition Of Forage Plants And Use Of Supplements, A. C. Esplin, J. E. Greaves, L. A. Stoddart

UAES Bulletins

Range forage provides the foundation for the maintenance ration available for most sheep wintered in Utah. The nature and amount of supplemental concentrate or roughage needed with this forage to provide an adequate and efficient ration for sheep naturally depends on the nature and amount of range forage available. Present uncertainty as to the relative merits of the various available supplements originates largely through a lack of definite knowledge as to the composition and feeding value of the various range plants that go to make up the range-forage supply on the particular range in question.

E. J. Maynard


The Effects Of X-Rays Upon The Roots Of Zea Mays, Bernard Louis Wolfe Jun 1937

The Effects Of X-Rays Upon The Roots Of Zea Mays, Bernard Louis Wolfe

Bachelors’ Theses

Since. the discovery of X-rays by Rontgen in 1895, the majority of published papers dealing with the influence of these rays on plant life have considered their general effects on physiological processes including rate of seed germination and growth, respiration, and movements. A large number of investigators have worked on the morphological and cytological aspects while comparatively few workers have been interested in the histological effects of the stimulated tissues. The purpose of this thesis is to show the histological, morphological, and cytological effects of X-rays upon the root tips or the Zea Mays as well as the effects these …