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Determination Of Minimum Lethal Level Of Toxaphene As A Piscicide In Lakes Of North Dakota, Dale L. Henegar Jan 1961

Determination Of Minimum Lethal Level Of Toxaphene As A Piscicide In Lakes Of North Dakota, Dale L. Henegar

Electronic Theses and Dissertations

Toxaphene as a piscicide for localized field application has not been widely used because minimum lethal concentrations have not been in the field. There is, however, considerable information gained from laboratory bio-assay studies (Surber, 1498; Duedoreff, et al. 1953; Hooper and Grzenda, 1955, et al. 1959). Concentrations indicated by such studies are not necessarily correct for field use. Prevost (1960) pointed out that results from controlled laboratory experiments do not always yield dosages exhibiting similar results in the field where a number of variables, both known and unknown, exist over which the field worker has little or no control. Gebhards …


Manage Your Rainfall For Maximum Production, J E. Watson Jan 1961

Manage Your Rainfall For Maximum Production, J E. Watson

Journal of the Department of Agriculture, Western Australia, Series 4

TTOW much would an extra inch of rainfall be worth to you? Much sloping land loses this much and more by run-off every year.

The soil is the main asset of your farm, but your profits depend on how you manage the rain which falls on it.


Special Report (1960), Walter A. Lawrance Nov 1960

Special Report (1960), Walter A. Lawrance

Walter Lawrance Papers

No abstract provided.


Odor Report (1960), Walter A. Lawrance Nov 1960

Odor Report (1960), Walter A. Lawrance

Walter Lawrance Papers

No abstract provided.


Addition Of Sodium Nitrate (1960), Walter A. Lawrance Nov 1960

Addition Of Sodium Nitrate (1960), Walter A. Lawrance

Walter Lawrance Papers

No abstract provided.


Analytical Data (1960), Walter A. Lawrance Nov 1960

Analytical Data (1960), Walter A. Lawrance

Walter Lawrance Papers

No abstract provided.


Press Report (1960), Walter A. Lawrance Nov 1960

Press Report (1960), Walter A. Lawrance

Walter Lawrance Papers

No abstract provided.


Irrigation And Drainage Problems In Uruguay, Jerald Emmet Christiansen Jun 1960

Irrigation And Drainage Problems In Uruguay, Jerald Emmet Christiansen

Reports

Synopsis: Uruguay irrigates about 65,000 acres, mostly rice (74%) and sugar cane (15%). Summer rainfall averages about 3.5 in. per month, but frequent droughts seriously affect both crops and livestock. Irrigation can be increased by storage in small reservoirs on tributary streams by means of low earth dams. Some areas will require flood control and draiange before intensive agriculture can be practiced.


The Effects Of Flouride Ion On Some Blood Constituents Of Rainbow Trout, Salmo Gairdneri, Linnaeus, Richard H. Alger May 1960

The Effects Of Flouride Ion On Some Blood Constituents Of Rainbow Trout, Salmo Gairdneri, Linnaeus, Richard H. Alger

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

During the past quarter of a century there has been considerable investigation into the effects of fluorides on living organisms. It has been well established, as a result of these studies, that both small and elevated amounts of fluorides present in the environment may have a marked toxic effect upon gaining entry into the organism. Much of the research involving fluorides and the living organism has been confined to experimentation with animals, although considerable evidence indicates that plants are also subject to injury if fluorides are present in the atmosphere or the soil.

The great majority of the research dealing …


Life History Notes On The Walleye, Stizostedion Vitreum Vitreum (Mitchill) In A Turbid Water, Utah Lake, Utah, Billy B. Arnold May 1960

Life History Notes On The Walleye, Stizostedion Vitreum Vitreum (Mitchill) In A Turbid Water, Utah Lake, Utah, Billy B. Arnold

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Early in 1952, walleye fry were stocked for the first time in Utah Lake. Subsequent plants were made in 1954, 1955 and 1956. Altogether, over two million fry have been stocked.

By January, 1958, it was felt sufficient time had elapsed for the species to establish patterns of growth, reproduction, food habits and consequent relationships to the new environment. Thus, on January 1, 1958, a Federal Aid to Fisheries project, number DJ F-4-R-5, job T, was initiated. This project was entitled "investigations of Yellow Pikeperch and Channel Catfish of Utah Lake, Utah County." Although the closing date was December 31, …


Preliminary Report: Monolayer Behavior Studies, 1959, Bureau Of Reclamation Jan 1960

Preliminary Report: Monolayer Behavior Studies, 1959, Bureau Of Reclamation

Publications (WR)

During the fall of 1959, monolayer behavior studies were made on two lakes in the southwest; Boulder Basin of Lake Mead, Nevada, and Lake Sahuaro near Phoenix, Arizona. These studies were made to evaluate the effect of geographical and climatological conditions on movement and behavior of monolayers. The Lake Sahuaro tests also were used to provide data for design and development of improved methods of application and maintenance of a film on this lake in anticipation of full scale, evaporation-reduction tests to be performed there during the summer of I960. The Lake Mead studies produced the following general points of …


The Nebraska Sandhill Lakes: Their Characteristics And Fisheries Management Problems, D. B. Mccarraher Jan 1960

The Nebraska Sandhill Lakes: Their Characteristics And Fisheries Management Problems, D. B. Mccarraher

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

A brief look at the map of Nebraska will readily point out the obvious fact that the sandhills comprise a considerable portion of the land area of the state. To be more precise, an area encompassing around 20,000 square miles or about one quarter of the total state area. This is indeed a vast prairie region long noted for its fine cattle and native hay crops. It is a region of vegetative dune sandhills, sandy basins and valleys, exposed ground water, spring seep lakes and marshes. Since much is already known concerning the land portion of the sandhills it is …


Financial Management Of Large Forest Ownerships, John Fedkiw, William L. Moise, Walter H. Meyer, Meade Whitaker, Henry I. Barclay Jr., C. G. Mclaren, J. A. Segur Jan 1960

Financial Management Of Large Forest Ownerships, John Fedkiw, William L. Moise, Walter H. Meyer, Meade Whitaker, Henry I. Barclay Jr., C. G. Mclaren, J. A. Segur

Yale School of the Environment Bulletin Series

No abstract provided.


Contour Banks For Filling Dams, B A'B Marsh Jan 1960

Contour Banks For Filling Dams, B A'B Marsh

Journal of the Department of Agriculture, Western Australia, Series 4

A LTHOUGH contour banks have been used in this State for many years to lead water into earth tanks or "dams," it is only comparatively recently that the idea has become really popular.

Thanks to the publicity given to this matter during the last three years many farmers now know that dams may be filled by contour banks, but because they do not know the finer points of the method, they are apt to mislead themselves into thinking that their territory is unsuitable for putting it into practice.


Rabbit Control In 1960, C Marshall Jan 1960

Rabbit Control In 1960, C Marshall

Journal of the Department of Agriculture, Western Australia, Series 4

IN the year 1859, an enthusiastic sportsman in Victoria took delivery from the clipper "Lightning" of a small consignment of wild European rabbits which he joyfully released on his estate at Barwon Park, near Geelong, in order to assure himself of some rough shooting.

He was not the only rabbit importer on record—tame rabbits were brought into Australia before and after 1895 and doubtless there were other importations of the wild rabbit—but he is generally credited—or discredited—with having triggered off the rabbit plague.


Drought Feeding Of Sheep, Laurence C. Snook Jan 1960

Drought Feeding Of Sheep, Laurence C. Snook

Journal of the Department of Agriculture, Western Australia, Series 4

WHEN this talk on drought feeding of sheep was suggested conditions were very serious over large tracts of pastoral country.

Many stations had not received a worthwhile rain for over 12 months and it appeared that grazing animals would have to be fed if they were to survive.

Requests have been received for advice on the cheapest way to keep sheep alive. Drought feeding in any form is a gamble. There is always the risk that the stock will eventually die despite the consumption of much costly feed.

It follows that if an effort is to be made to save …


Reclaiming Salt Land With Bluebush, Stanley Thomas Smith Jan 1960

Reclaiming Salt Land With Bluebush, Stanley Thomas Smith

Journal of the Department of Agriculture, Western Australia, Series 4

IN Western Australia there are approximately a million acres of salt land, some of which is a serious economic problem to individual farmers, unfortunate enough to have the major portion of their properties affected by salt encroachment.


Bluebush Seed Supplies, C V. Malcolm Jan 1960

Bluebush Seed Supplies, C V. Malcolm

Journal of the Department of Agriculture, Western Australia, Series 4

A GREAT deal of publicity has been given of late to the value of bluebush (Kochia brevifolia) as a plant for some types of salt-affected land, particularly in the drier parts of the wheatbelt.

Obtaining seed supplies can be a problem, but fortunately large amounts of seed are not required since once a few bushes are established they will spread seed over the intervening areas.

Thus rates of 1 to 2 lb of seed per acre have been found quite satisfactory.


Distribution And Undesirable Characteristics Of Certain Wild Birds And Animals Barred From Importation Or Restricted In Importation Into The State Of California, Walter S. Ball Jan 1960

Distribution And Undesirable Characteristics Of Certain Wild Birds And Animals Barred From Importation Or Restricted In Importation Into The State Of California, Walter S. Ball

Other Publications in Wildlife Management

The legislative act governing the importation of wild birds and animals into the State of California is set forth in Division 3, Chapter 2, Articles 1, 2 and 3 of the Fish and Game Code. This law is specific in its treatment of all questionable species. The joint regulations of the Fish and Game Commission and the Department of Agriculture governing the importation of wild birds and animals, and conditions under which same may be kept in confinement are set forth in Part 3, Chapter 3, Section 671, Title 14 of the California Administrative Code.

All species and families listed …


The Dispersal And Acclimatization Of The Muskrat, Ondatra Zibethicus (L.), In Finland, Atso Artimo Jan 1960

The Dispersal And Acclimatization Of The Muskrat, Ondatra Zibethicus (L.), In Finland, Atso Artimo

Other Publications in Wildlife Management

The natural range of the muskrat, Ondatra zibethicus (L.), comprises the major part of the North American continent (Fig. 1). In the northern and eastern parts of its range its distribution is more or less continuous, but in the arid west it is very patchy. The species is absent from some areas which, according to Storer (1938), are suitable for it. This writer assumes (op.cit. pp. 159-160) that »Muskrats probably reached some of the now isolated waters of the West during a period when aquatic and palustrine habitats were more widespread, in late Pleistocene or postglacial times. With subsequent contraction …


Overcoming Stock Watering Problems In The Kimberleys, B Swan Jan 1960

Overcoming Stock Watering Problems In The Kimberleys, B Swan

Journal of the Department of Agriculture, Western Australia, Series 4

ONE of the ever-present problems of the pastoral areas is that of providing: watering-points in reasonably close proximity to the grazing areas.

All too frequently, the country on the river frontages and that in the vicinity of the water-holes becomes eaten out and although there may be ample feed on other portions of the run, it is too far distant from the available water to be effectively utilised.


Deferred Grazing : What It May Mean In The Mulga Region, W M. Nunn Jan 1960

Deferred Grazing : What It May Mean In The Mulga Region, W M. Nunn

Journal of the Department of Agriculture, Western Australia, Series 4

THE practice of deferred grazing has been written up in American textbooks and has been applied effectively to sections of the cattle range lands of the United States.

Early attempts to apply the principle in eastern Australia were not very successful, and it remained for our Departmental workers in the North-West and Kimberley Divisions to demonstrate the phenomenal results that could be obtained on grasslands in summer rainfall areas.


Wild Life In A Modern Age, Clee Francis Howard Jenkins Jan 1960

Wild Life In A Modern Age, Clee Francis Howard Jenkins

Journal of the Department of Agriculture, Western Australia, Series 4

THE present human population of the earth is estimated at about 2 1/2 thousand million, and reliable sources consider that this figure will be doubled by the year 2000.

Although the pessimistic forecasts of Malthus have not yet come true, it is obvious that the world's food requirements, must lead to increased exploitation of land and other primary resources, with consequent repercussions on all forms of wild life.


Weed Research. 7. Weed Control Around The Yard, Geoffrey A. Pearce Jan 1960

Weed Research. 7. Weed Control Around The Yard, Geoffrey A. Pearce

Journal of the Department of Agriculture, Western Australia, Series 4

MANY farmers and city householders have weed problems around houses and sheds which can be readily overcome by treatment with appropriate herbicides.

The risk from fire through weeds and unslightly growth can easily be removed and an area free of any plant growth can be maintained with little effort for a considerable period.


Soil Conservation In The Kimberley Area Of Western Australia, K Fitzgerald Jan 1960

Soil Conservation In The Kimberley Area Of Western Australia, K Fitzgerald

Journal of the Department of Agriculture, Western Australia, Series 4

OFFICERS of the Soil Conservation Branch of the West Australian Department of Agriculture, have not been engaged in soil conservation work in the Kimberleys prior to this year, not because a serious erosion problem did not exist, but rather because with limited trained staff available they were too fully occupied elsewhere.

The recent arrival of a senior Soil Conservation Officer in the area to assist and plan an approach to the problem of soil erosion in the Ord River catchment area is therefore very welcome.


Water Usage Trials With Bananas On The Gascoyne, W M. Nunn Jan 1960

Water Usage Trials With Bananas On The Gascoyne, W M. Nunn

Journal of the Department of Agriculture, Western Australia, Series 4

THE banana industry at Carnarvon is an unusual one by most agricultural standards.

Normally a tropical plant liking relatively humid conditions in a high rainfall, the banana is cultivated at Carnarvon in an area of extremely low rainfall and with relatively low humidity throughout the year.

Water is pumped to irrigate the crop from the sands of the Gascoyne River bed or from bores adjacent to the river course.


Some Limnological Conditions Relative To Winter Kill Of Fish In Ice-Covered Representative Farm Ponds In Eastern South Dakota, Jerome L. Johnson Jan 1960

Some Limnological Conditions Relative To Winter Kill Of Fish In Ice-Covered Representative Farm Ponds In Eastern South Dakota, Jerome L. Johnson

Electronic Theses and Dissertations

An aquatic environment involves many complex relationships biologically, physically, and chemically. Many of these relationships are difficult to measure or are little understood. In nature, aquatic environments accommodate many types of aquatic life. Ecological disturbances may cause the environment to become unfit for economically important forms of life. Human interferences often causes polluted waters and naturally occurring disturbances are common. A disturbance of this kind is one of the major problems of fisheries management in the northern Great Plains area – seasonal anaerobosis of fish or other aquatic animals and plants, commonly known as winter kill. Winter kill is usually …


Comprehensive Survey Of Sedimentation In Lake Mead, 1948-49, W. O. Smith, C. P. Vetter, G. B. Cummings, U.S. Bureau Of Reclamation Jan 1960

Comprehensive Survey Of Sedimentation In Lake Mead, 1948-49, W. O. Smith, C. P. Vetter, G. B. Cummings, U.S. Bureau Of Reclamation

Publications (WR)

Reservoirs are becoming an increasingly prominent feature of the American landscape. Built for flood mitigation and to change a fluctuating river into a dependable source of water for irrigation, power, and other purposes, they are predestined, like natural lakes, to be destroyed sometime following their creation. Sedimentation sooner or later robs most lakes and reservoirs of their capacity to store water. The significance of sedimentation in the life of Lake Mead, the largest artificial reservoir in the world, was realized when the plan for the reservoir was conceived, and an aerial survey of the floor was made in 1935 before …


Pike Hybrids (Esox Lucius X E. Vermiculatus) In A Sandhill Lake, Nebraska, D. B. Mccarraher Jan 1960

Pike Hybrids (Esox Lucius X E. Vermiculatus) In A Sandhill Lake, Nebraska, D. B. Mccarraher

Nebraska Game and Parks Commission: Staff Research Publications

In the sandhill region of Nebraska both northern pike, Esox lucius, and grass pickerel, Esox vermiculatus, are abundant in several shallow natural lakes. Both species are known to utilize the same vegetative habitat for spawning during March and April. The pike is an important game species but the smaller pickerel is of little value to fishermen although in winter is at times taken by angling through the ice.


Upland Game Restoration Project, Melvin O. Steen, Willard R. Barbee, C. Phillip Agee, Clarence E. Newton Jan 1960

Upland Game Restoration Project, Melvin O. Steen, Willard R. Barbee, C. Phillip Agee, Clarence E. Newton

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

It is the objective of the project to stabilize the populations of various species of small, upland game to the extent that populations will be maintained at harvestable levels in periods when those populations tend to slump.

It is recognized that in Nebraska nearly all of the small, upland game is produced on private lands. Therefore, the project is designed to provide assistance to the landowners who may wish to improve the game habitat on their lands.