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How To Control Undesirable Trees And Shrubs, Maurice W. Day May 1950

How To Control Undesirable Trees And Shrubs, Maurice W. Day

Aspen Bibliography

No abstract provided.


Microradiography With Biological Specimens, Arthur D. Wellman May 1950

Microradiography With Biological Specimens, Arthur D. Wellman

Bachelors’ Theses

Microradiography is a technique in which X-rays are directed through a very thin specimen onto a fine-grained photographic film and the image examined under magnification. It has been used chiefly as a supplementary tool in industrial analysis of metal structures, and even in this field has attained prominence only within the past decade. Its usefulness is limited to fine structures (except where minute flaws or impurities are to be examined in a material), and its success is limited by the degree of clarity in the radiograph to be magnified.


Actinomycetes Of Virgin Utah Soils With Special Reference To Antagonisms, Paul H. Krumperman May 1950

Actinomycetes Of Virgin Utah Soils With Special Reference To Antagonisms, Paul H. Krumperman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The importance of actinomycetes in the soils was generally overlooked until about 1913. The investigators Hiltner and Stormer and Beijerinck began systemtaic study of their occurrence and role in soil fertility. The work done by these men and others since 1913 has proved actinomycetes to occur abundantly in most soils of the world. This work done by these men and others since 1913 has proved actinomycetes to occur abundantly in most soils of the world. This work has also proved the function of these organisms to be that of decomposing highly resistant materials such as humus and complex polysaccharide compounds. …


The Food Of Three Centrarchids And An Ameiurid In Northern Utah During 1949-50, Robert L. Eberhardt May 1950

The Food Of Three Centrarchids And An Ameiurid In Northern Utah During 1949-50, Robert L. Eberhardt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This is a study of the food of pond fish in northern Utah. The species examined in the family Centrarchidae were largemouth black bass, Micropterus salmoides (Lacepede), green sunfish, Lepomis cyanellus Rafinesque, and common bluegill, Lepomis macrochirus Rafinesque, together with black bullhead, Ameiurus melas (Rafinesque) of the family Ameriuridae. Specifically it is a report of the macroscopic food found in the stomachs of sub-adult and mature fish. Although such a study is of predominant interest to the biologist, who is interested in life history and ecological relationships of fish, the farmer or small businessman can find the data applicable. This …


Hive And Field Mortality Of Honey Bees In Northern Utah Due To Effects Of Certain Ecological And Chemical Factors, Shih Chun Ma May 1950

Hive And Field Mortality Of Honey Bees In Northern Utah Due To Effects Of Certain Ecological And Chemical Factors, Shih Chun Ma

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The honey bee is the most important pollinating insect in Utah, because various important crops such as fruits, legumes, and vegetable seed crops depend chiefly on it for pollination. In the past, honey bees have suffered repeated severe death losses through contact with arsenic and other agricultural chemicals. Recently the newer insecticides, such as DDT, chlordane, parathion, benzene hexachloride, lindane, toxaphene, and several kinds of miticides have further complicated the problem of bee survival. In addition, natural enemies such as predators and parasites and some unfavorable environmental conditions, including unfavorable temperature and humidity, wind, storm, and other changeable weather conditions, …


A Survey Of Plant Parasitic And Associated Species Of Nematodes In The Carrot Producing Area Of Cedar Valley, Iron County, Utah, Paul R. Fitzgerald May 1950

A Survey Of Plant Parasitic And Associated Species Of Nematodes In The Carrot Producing Area Of Cedar Valley, Iron County, Utah, Paul R. Fitzgerald

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Plant parasitic nematodes have long been known to cause extensive crop losses through reduced yields, shortened productive life, or lowered value of produce. The rood knot nematode, Heterodera marioni, is cosmopolitan. It destroys crops and causes economic losses equal to those of any other plant parasitic species. in 1948 this nematode caused an estimated loss to the carrot raising industry in Iron County, Utah of approximately $15,000. No estimates for the years prior to 1948 are available; however, reports of the county agent (14) for Iron County show that carrot production in the Cedar Valley is decreasing, and is …


Harvest Of Wild And Stocked Fish From The Logan River Drainage, Louis S. Pechacek May 1950

Harvest Of Wild And Stocked Fish From The Logan River Drainage, Louis S. Pechacek

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Logan River, one of Utah's better trout streams, has carried more than its share of the increased fishing pressure of the past few years. Careful management of the drainage by the U.S. Forest Service has kept the Logan River free of serious water fluctuations and relatively unpolluted by silt and wastes. The only noticeable fluctuations in the stream is the annual runoff cycle which usually reaches its peak in May. This alone has contributed greatly to the ability of the river to withstand the increased fishing pressure which it has done quite well. The increase in fishing pressure can …


Leafhoppers (Cicadellidae) Associated With The Stone Fruit Orchards Of Northern Utah, Mervin W. Nielson May 1950

Leafhoppers (Cicadellidae) Associated With The Stone Fruit Orchards Of Northern Utah, Mervin W. Nielson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Virus diseases of stone fruit orchards have existed in Utah for more than a quarter of a century and are seriously diminishing the peach and cherry fruit production. Western X of peach, rusty mottle of cherry, wilt and decline of cherry, and little cherry constitute the most economically important stone fruit virus diseases in Utah. Many orchards, particularly in Davis County, have 50 to 83 percent of the trees infected with one or more of the yellow-red viroses. Surveys have shown that the diseases are spreading from 3 to 5 percent each year. It is believed that certain insects are …


Some Factors Which May Influence Survival Of Game Farm-Reared Pheasants After Release Into The Wild, Taylor F. Cottle May 1950

Some Factors Which May Influence Survival Of Game Farm-Reared Pheasants After Release Into The Wild, Taylor F. Cottle

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was undertaken in an attempt to determine some of the factors which may influence the survival of Utah game farm-reared pheasants following their release into the wild. The survival of these birds is below the desired level after they are released, as is indicated by the low percentage taken by the sportsmen during the hunting season. In recent years the return from released game farm-reared pheasants is about 7 to 8 percent.1 Consequently, if survival rate of these birds could be increased, more birds would be available to supplement the wild stock. Also, an increase in the …


The Sixty-Second Session Of The Iowa Academy Of Science And The Seventeenth Convention Of The Junior Academy Of Science Of Iowa, April 21 And 22, 1950, Iowa Academy Of Science Apr 1950

The Sixty-Second Session Of The Iowa Academy Of Science And The Seventeenth Convention Of The Junior Academy Of Science Of Iowa, April 21 And 22, 1950, Iowa Academy Of Science

Iowa Academy of Science Documents

No abstract provided.


Texas Species Of Desmanthus (Legurminosae), B. L. Turner Apr 1950

Texas Species Of Desmanthus (Legurminosae), B. L. Turner

Field and Laboratory

The Texas species of Desmanthus (nomen conservandum), as treated in the present paper, total nine, one of which has two varieties. Six of these are found almost exclusively within the state.


The Species Of Matelea (Including Gonolobus) In North Central Texas (Asclepiadaceae), Lloyd H. Shinners Apr 1950

The Species Of Matelea (Including Gonolobus) In North Central Texas (Asclepiadaceae), Lloyd H. Shinners

Field and Laboratory

MATELEA gonocarpa (Walter) Shinners, comb. nov. Vincetoxicum gonocarpos Walt., Fl. Carol. 104. 1788. (Emend. Gray and Perry.) Gonolobus gonocarpos (Walt.) Perry, Rhodora 40: 284. 1938.


The Distribution Of Wallengrenia Otho (Abbot & Smith) And Its Subspecies In The United States (Lepidoptera, Rhopalocera, Hesperiidae), H. A. Freeman Apr 1950

The Distribution Of Wallengrenia Otho (Abbot & Smith) And Its Subspecies In The United States (Lepidoptera, Rhopalocera, Hesperiidae), H. A. Freeman

Field and Laboratory

No abstract provided.


Some Books About Botanical Explorers Of The Western Part Of The United States, S. W. Geiser Apr 1950

Some Books About Botanical Explorers Of The Western Part Of The United States, S. W. Geiser

Field and Laboratory

No abstract provided.


The Distribution And Flower Preferences Of The Theclinae Of Texas (Lepidoptera, Rhopalocera, Lycaenidae), H. A. Freeman Apr 1950

The Distribution And Flower Preferences Of The Theclinae Of Texas (Lepidoptera, Rhopalocera, Lycaenidae), H. A. Freeman

Field and Laboratory

In 1944 I began work on the hairstreaks of North America. Since that year, nine new records for the United States, and one new species, were found in the vicinity of Pharr, Hidalgo County, Texas. While collecting over the State, I have found thirty-three species, five subspecies, and two forms, representing five genera of hairstreaks. One new Texas record is reported in this paper, Mitoura siva (Edw.) Most of the information contained here was obtained at first hand; but the fine collection of Stallings and Turner, at Caldwell, Kansas, was checked for Texas specimens.


Gomphus Maxwelli, A New Species Of Dragonfly From Texas (Odonata, Gomphinae, Group Arigomphus), Alice Ferguson Apr 1950

Gomphus Maxwelli, A New Species Of Dragonfly From Texas (Odonata, Gomphinae, Group Arigomphus), Alice Ferguson

Field and Laboratory

Four males of the species herein described as new, were collected by Dr. Richard E. Maxwell in Hardin County. Texas, May 11, 1940. Hardin County is in the Big Thicket area of southeastern Texas, where long and short leaf pines are common. The annual precipitation is c. 50 inches; springs, bogs and ponds are frequent; and the humidity is high.


Variations In The Vertebrae And Pelvis Of Necturus, Joseph P. Harris Jr. Apr 1950

Variations In The Vertebrae And Pelvis Of Necturus, Joseph P. Harris Jr.

Field and Laboratory

In most specimens of Necturus, the nineteenth vertebra serves as the sacrum; the iliac processes of the pelvic girdle articulate with it. In a number of specimens, Vertebra XX or (less frequently) Vertebra XVIII serves as the sacrum. But not always do the two iliac processes join the same vertebra. The iliac process of the left side may join the XVIII, XIX, or XX vertebra. The converse may also occur.


Ranunculus Carolinianus Dc. Var. Villicaulis Shinners, Var. Nov., Lloyd H. Shinners Apr 1950

Ranunculus Carolinianus Dc. Var. Villicaulis Shinners, Var. Nov., Lloyd H. Shinners

Field and Laboratory

No abstract provided.


Whole Issue Nebraska Bird Review (April 1950) 18(2) Apr 1950

Whole Issue Nebraska Bird Review (April 1950) 18(2)

Nebraska Bird Review

Contents

Twenty-five Year Summary of Bird Migration in Nebraska, Part 2.....William F. Rapp, Jr. ..............23

News and Notes ..............25

Report of the Membership Committee 29

Wildfowl Sketches....C.G. Pritchard ..............30

Announcements ..............32

General Notes ..............32

Periodicals in the Nebraska Ornithologists' Union Library ..............36

Book Reviews ..............39


Rodent Populations And Activities On A Moderately Grazed Mixed Prairie Near Hays, Kansas, John L. Paulk Mar 1950

Rodent Populations And Activities On A Moderately Grazed Mixed Prairie Near Hays, Kansas, John L. Paulk

Master's Theses or Doctor of Nursing Practice

The purpose of this investigation was to study rodent populations on a moderately grazed mixed prairie. A working knowledge of the activities of these small mammals, has satisfied to a certain degree the curiosity of the writer. So little work has been done in this plains region that the author felt the need for such an investigation, and hoped to arouse the interest of others along similar lines.


Microorganisms And Soil Structure, T. M. Mccalla Mar 1950

Microorganisms And Soil Structure, T. M. Mccalla

Department of Agronomy and Horticulture: Faculty Publications

SUMMARY

Laboratory tests were made to determine the effectiveness of different compounds and microbial groups in increasing the stability of Peorian loess lumps against the action of falling water drops. The influence of these on percolation tests in the laboratory was also determined.

Many organic substances-dextrose, sucrose, starch, peptone, cullulose, and gum arabic-did not themselves contribute directly to soil-structure stability, though these substances do furnish energy material for soil microorganisms, which can convert them readily into either microbial tissue or decomposition products that increase soil-structure stability. Lignin, proteins, oils, fats, waxes, resin, and paraffin increased the stability of lumps of …


Science And Supposition In Evolution, Geology, And Astronomy, D. A. Sommer Jan 1950

Science And Supposition In Evolution, Geology, And Astronomy, D. A. Sommer

Stone-Campbell Books

No abstract provided.


Pollination (In Growing Alfalfa For Seed In Utah), F. E. Todd, George E. Bohart, William P. Nye Jan 1950

Pollination (In Growing Alfalfa For Seed In Utah), F. E. Todd, George E. Bohart, William P. Nye

All PIRU Publications

No abstract provided.


Rate Of Deterioration Of Beetle-Killed Engelmann Spruce, James L. Mielke Jan 1950

Rate Of Deterioration Of Beetle-Killed Engelmann Spruce, James L. Mielke

The Bark Beetles, Fuels, and Fire Bibliography

Examination of beetle-killed stands in Utah and Colorado indicate that dead Engelmann Spruce will remain standing and sound for at least 20 years.


Further Observations On Calpodes Evansi Freeman (Lepidoptera, Rhopalocera, Hesperiidae), H. A. Freeman Jan 1950

Further Observations On Calpodes Evansi Freeman (Lepidoptera, Rhopalocera, Hesperiidae), H. A. Freeman

Field and Laboratory

This beautiful tropical-American skipper is figured here for the first time.


The Texas Species Of Thelesperma (Compositae), Lloyd H. Shinners Jan 1950

The Texas Species Of Thelesperma (Compositae), Lloyd H. Shinners

Field and Laboratory

Seven genera of Compositae-Heliantheae-Coreopsidinae as delimited by Hoffman (1894) are found in Texas….Thelesperma has been the subject of partial synopses and extended. notes (Gray, 1884; Rydberg, 1900; Blake, 1928), but has never been revised. The genus reaches its greatest development in Texas and northern Mexico; seven of the thirteen known species are included in the following synopsis. The remaining six are listed at the end for the convenience of those interested.


Whole Issue Nebraska Bird Review (Jan 1950) 18(1) Jan 1950

Whole Issue Nebraska Bird Review (Jan 1950) 18(1)

Nebraska Bird Review

Contents

Nesting Birds on a Keith County Farm.............Mrs. Carl N. Collister .............1

Twenty-five Year Summary of Bird Migration in Nebraska
William F. Rapp .............5

Announcements .............11

Pictorial Study of a nesting Eastern Red-Wing.....Adrian C. Fox .............12

General Notes .............14

Membership List............. 18

Book Reviews .............21


Notes On Texas Compositae - Iv, Lloyd H. Shinners Jan 1950

Notes On Texas Compositae - Iv, Lloyd H. Shinners

Field and Laboratory

No abstract provided.


Tables Illustrating Biparental Crossing-Over In Genetics, S. W. Geiser Jan 1950

Tables Illustrating Biparental Crossing-Over In Genetics, S. W. Geiser

Field and Laboratory

Students of elementary genetics frequently are called upon to calculate the theoretical distribution into phenotypic and genotypic classes, of populations resulting from divers crosses with linked genes, say (A and B).


Salmonella And Paracolon Species Isolated From The Wild Brown Rat, Rattus Norvegicus, In The City Of Richmond, Virginia, John Miles Sharpley Jan 1950

Salmonella And Paracolon Species Isolated From The Wild Brown Rat, Rattus Norvegicus, In The City Of Richmond, Virginia, John Miles Sharpley

Master's Theses

The importance of bacteria as a cause of serious intestinal diseases in man and. other animals has been recognized since the early days of the science of bacteriology. Of those forms usually associated with intestinal disturbances in man, the species considered most important are those belonging in the Salmonella group, the Paracolon group, and the Shigella group. Also, it has been known since the early part of this century that the conman rat serves as an important vector for the dissemination of infectious organisms. For example, standard textbooks list rats as primary vectors of enteric bacteria. However. there has been …