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Full-Text Articles in Environmental Health and Protection

Mole And Woodrat Control, Rex E. Marsh Feb 1962

Mole And Woodrat Control, Rex E. Marsh

Proceedings of the 1st Vertebrate Pest Conference (1962)

MOLES: In regions where moles thrive, lawns in golf courses, parks, cemeteries and home yards are often made unsightly by dirt mounds and ridges pushed up by the active little animals. In cultivated land, moles may cause consider¬able economic loss through their burrowings. Mole control can be divided into six basic categories: exclusion, repellents, gases, toxic baits, reduction of food supply, and trapping. Un¬changed over the years, trapping is still considered the most reliable of all methods of control, however, under certain conditions or situations, the other methods of control may be extremely useful. WOOD RATS: The native wood rat …


Control Of Pocket Gophers, Maynard W. Cummings Feb 1962

Control Of Pocket Gophers, Maynard W. Cummings

Proceedings of the 1st Vertebrate Pest Conference (1962)

Pocket gophers occur only in North and Central America but within this vast area few other native rodent groups are more widely distributed (Anthony, 1928). None are more adaptable, either to natural extremes of habitat or to changed conditions brought about by agricultural development and other man-made environmental modifications. They occupy coastal areas, inland plains and valleys, desert and alpine meadow, from sea level to above timber line in a multitude of vegetation and soil types. This practically universal distribution has, of course, led to the recognition by naturalists of many species and subspecies. California alone contains at least 75 …


Controlling Muskrats, Rollo E. Talbert Feb 1962

Controlling Muskrats, Rollo E. Talbert

Proceedings of the 1st Vertebrate Pest Conference (1962)

Today damage attributed to muskrat activities occurs both to irrigation systems and waterways serving agricultural interests as well as to power company installations, waterfowl refuges and hunting clubs. Direct damage or destruction of agricultural crops is relatively minor although the muskrat is known to feed on a variety of produce including ear corn, alfalfa, clover and carrots and frequently will cut a rather wide swath of rice near water control boxes separating rice paddies. The brief activities of fur trappers appear to have little significance as applied to alleviating these losses, so we are forced to recognize that we will …


Controlling Yellow-Billed Magpies (Pica Nuttalli), Rex Lynda Ii Feb 1962

Controlling Yellow-Billed Magpies (Pica Nuttalli), Rex Lynda Ii

Proceedings of the 1st Vertebrate Pest Conference (1962)

The yellow-billed magpie is a little smaller than the American or black-billed magpie, but the difference in size is very slight. The birds look exactly alike, except one has a black beak and the other has a yellow bill and a bit of yellow skin back of the eye.There are concentrated populations in the Los Banos area, Gustine area, and along the course of the Merced River comprising about 19,100 acres. They are occasionally seen in other areas of the County, but only infrequently observed in the southwestern portion of the County. The heaviest populations are in walnut orchards, dairy …


The Pest Animal Problem: Keynote Speech, W. C. Jacobsen Feb 1962

The Pest Animal Problem: Keynote Speech, W. C. Jacobsen

Proceedings of the 1st Vertebrate Pest Conference (1962)

There is an inscription across the top of the impressive facade of the National Archives Temple in Washington, D. 0., which reads: "What is Past is Prologue." So be it. Perhaps it applies to us here- At least the inscription furnishes a basis for me to indulge in a few com¬ments of historical significance as we undertake consideration of vertebrate pest control in its many phases. The earlier documents available to us reveal that with every expansion or westward advance into newer areas of agricultural production or livestock enterprises there also arose a variety of pest animal problems. However, it …


Meeting The Meadow Mouse Menace, William D. Fitzwater Feb 1962

Meeting The Meadow Mouse Menace, William D. Fitzwater

Proceedings of the 1st Vertebrate Pest Conference (1962)

The orchardist has many ways to lose money but one of the best is to ignore his mouse problem. This apparently insignificant, short-tailed little rodent by his unobtrusive but systematic attacks on the growing tissue of trees can be very expensive. The Indiana Extension Horticulturist has stated that mice are the number one cause for orchardists going out of business in recent years in that State. Moreover, the problem is not a recent one as a questionnaire to county agricultural agents in 1924 (Davis, 1925) showed that field mice were even then considered a problem in 40 per cent of …


Banquet Address: People, Pests And Some Plans, Daniel G. Aldrich Jr. Feb 1962

Banquet Address: People, Pests And Some Plans, Daniel G. Aldrich Jr.

Proceedings of the 1st Vertebrate Pest Conference (1962)

We can probably say that the California way of farming has made California fanners the most over-run hosts to vertebrate pests in the agricultural world. We can certainly say, too, that new pests—and here I don't mean people--are on their way. I'm told that the starlings are just exploring here now. The relatives are coming later. We'll see, and hear, a lot more of them. Our problem is: How do we keep from being such good hosts to our small vertebrate guests? I have been told by experts that right now the vertebrate pest control man is woefully underequipped for …


Control Of Meadow Mice, Kangaroo Rats, Prairie Dogs,, John A. Ludeman Feb 1962

Control Of Meadow Mice, Kangaroo Rats, Prairie Dogs,, John A. Ludeman

Proceedings of the 1st Vertebrate Pest Conference (1962)

Meadow mice, kangaroo rats, prairie dogs and cotton rats are broadly classified as field rodents. The control of their populations have been necessary since man first began to farm and raise livestock within the areas in which these rodents live. The intensity of control has varied with land values and the population fluctuation of the rodents. Rodent control, like other farming practices must be profitable to the land owner, or he cannot afford to undertake a control program. If he is to continue in business his control efforts must be done efficiently and as successfully as possible. To accomplish these …


Winter Management Of Salt Land, T C. Stoneman Jan 1962

Winter Management Of Salt Land, T C. Stoneman

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

WITH the emergence of crops, many farmers will again be seeing bare patches or thin stands of cereals due to salt accumulation.

Would these areas be better left out of cultivation, or should they have been planted to saltbush and bluebush?


Light Lands In Western Australia. 2. Their Nature, Distribution And Climate, George Henry Burvill Jan 1962

Light Lands In Western Australia. 2. Their Nature, Distribution And Climate, George Henry Burvill

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

LIGHT land development for agriculture is a major feature in the story of agriculture in Western Australia. Sixty years ago there was less than one million acres of arable land.

The total area planted to all crops was less than 250 thousand acres and the wheat harvest was less than one million bushels.


Stilling Coastal Sand Drifts With Marram Grass, J L. Mcmullan Jan 1962

Stilling Coastal Sand Drifts With Marram Grass, J L. Mcmullan

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

DRIFTS in dunes on the coast between Albany and Geraldton may be stabilised by planting marram grass (Ammophila arenaria).

However, it should be anticipated that much of the planted grass will die before an area is finally stabilised.


Farm Flora Sancturies, Robert Dunlop Royce Jan 1962

Farm Flora Sancturies, Robert Dunlop Royce

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

NOW that several species of native plants have become totally extinct and many more are becoming rare almost to the point of extinction, interest in the scientific and aesthetic potential of the West Australian flora is awakening.


Fallowing And Soil Conservation, J E. Watson Jan 1961

Fallowing And Soil Conservation, J E. Watson

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

Soil Conservationists don't always disapprove of fallowing, says Soil Conservation Service adviser J. E. Watson.

They are prepared to compromise, and accept fallowing as a useful practice where it means better pasture establishment or more effective land reclamation.


Flooding Of Salt Land, C V. Malcolm Jan 1961

Flooding Of Salt Land, C V. Malcolm

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

Many farmers have expressed concern and some have gone to considerable expense in trying to alleviate flooding problems on salt affected land.

Some consideration will be given here to flooding, its causes, effects on salt encroachment, methods of prevention and alleviation.


Palatability Of Forage Plants In North-West Sheep Pastures, R H. Collett Jan 1961

Palatability Of Forage Plants In North-West Sheep Pastures, R H. Collett

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

A DECLINE in carrying capacity has occurred in large areas of the Pilbara district of the North-West, due to the decrease in palatable plants and the increase in unpalatable ones.

The relative palatability of the various species to sheep is therefore a matter of considerable importance to pastoralists.


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.


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.


Industrial Wastes: Bio-Assays For Control Of Industrial Effluents, Croswell Henderson, Clarence M. Tarzwell Sep 1957

Industrial Wastes: Bio-Assays For Control Of Industrial Effluents, Croswell Henderson, Clarence M. Tarzwell

United States Environmental Protection Agency: Staff Publications

Waste effluents from many industries are toxic to fish and other aquatic life. The control or treatment of these wastes for safe release into receiving waters presents a problem of consider able magnitude.

Much effort has been expended by some industries to solve this problem, primarily through chemical analysis for possible toxic components and then generally by a search of the literature to find out how toxic a particular component may be. Unfortunately, this approach has not been successful, nor can it be expected to be productive of satisfactory answers.


Stream Pollution- Aquatic Macro-Invertebrate Communities As Indicators Of Organic Pollution In Lytle Creek, Arden R. Gaufin, Clarence M. Tarzwell Jul 1956

Stream Pollution- Aquatic Macro-Invertebrate Communities As Indicators Of Organic Pollution In Lytle Creek, Arden R. Gaufin, Clarence M. Tarzwell

United States Environmental Protection Agency: Staff Publications

Year-round field studies of the com position and ecology of stream communities associated with the purification of organic wastes in streams were initiated on Lytle Creek in October, 1949. This creek, which is located about 45 miles northeast of Cincinnati, Ohio, is a tributary of the Little Miami River. Its drainage basin comprises 27 sq. mi., a third of which is contained within the city limits of Wilmington, Ohio, a city of some 7,412 persons


Industrial Wastes, Charles E. Renn Mar 1955

Industrial Wastes, Charles E. Renn

United States Environmental Protection Agency: Staff Publications

This paper presents a summary of experiences with a variety of cyanogenic wastes. The work has attempted to evaluate the interaction of waste bearing waters and the environment in terms of waste disposal design requirements. In this, the approach is somewhat more critical than that commonly taken by fisheries biologists, conservationists, and others who have been concerned with the "preventive" aspects of waste disposal.

The first phases of the work were designed to discover the tolerable limits of certain waste components to fresh water fish. This was undertaken in 1950; in the interval the composition of the wastes has been …


Stream Pollution, Ruth Patrick Feb 1953

Stream Pollution, Ruth Patrick

United States Environmental Protection Agency: Staff Publications

This paper discusses the various ways in which aquatic organisms may be of use in solving problems associated with waste disposal. Since many state and federal laws set forth that nothing may be discharged that is deleterious to aquatic life, the most expedient way to determine the effect of an effluent is to study the aquatic organisms themselves.

In every river that has not been adversely affected by pollution there is a great variety of aquatic life. These organisms do not represent a great mass of living things, but rather they are organized into an intricately balance systems, often referred …


It's Time To Take Stock Apr 1950

It's Time To Take Stock

United States Environmental Protection Agency: Staff Publications

Likening colleges and universities to the automobile industry may seem far-fetched, but is it? Each is engaged in fashioning and selling necessary products- one trained men, the other mechanical equipment. Both entered the post-war years with production at low ebb; unable to satisfy pent-up customer demands. Time and high-speed assembly lines have bridged the gap of gas buggy shortage. The impact of selective buying by a discriminating public is now real cause for concern among some of the motor moguls. Rumor has had it that schools teaching wildlife management are overproducing. We decided to gather facts and opinions at the …


Public Health Reports, Clarence M. Tarzwell Feb 1950

Public Health Reports, Clarence M. Tarzwell

United States Environmental Protection Agency: Staff Publications

Preliminary tests with DDT for the control of mosquitoes, forest insects, and agricultural pests demonstrated that it was toxic to a wide variety of animal life. Because there were indications that the new insecticide would be widely used, apprehension was expressed by some groups that its extensive or indiscriminate use would cause extensive harm to wildlife.

The desirability of carefully controlled use was early recognized by those in charge of extensive programs for the control of insects of public health importance. A joint statement of policy for the use of DDT issued early in 1945 (1) by the Army and …


Observations On The Nighttime Resting And Biting Habits Of Anopheline Mosquitoes In Ddt-Treated And-Untreated Buildings, Clarence M. Tarzwell, Frank W. Fisk Jan 1947

Observations On The Nighttime Resting And Biting Habits Of Anopheline Mosquitoes In Ddt-Treated And-Untreated Buildings, Clarence M. Tarzwell, Frank W. Fisk

United States Environmental Protection Agency: Staff Publications

Laboratory cage tests and controlled experiments in houses have clearly demonstrated that residual-spray deposits of DDT are lethal to mosquitoes for considerable periods. Although these tests valuable information on the durability of DDT residual deposits, they did not give information on the mortality of malaria mosquitoes naturally entering treated dwellings in search of a blood meal. In order to secure a lethal dose of DDT from residual deposits, mosquitoes must actually touch the material and be exposed to it for a considerable period. This period has been shown to vary (1), depending on the temperature, age of treatment, density and …


The Feeding Habits Of Gambusia Affinis Affinis, With Special Reference To The Malaria Mosquito, Anopheles Quadrimaculatus, A.D. Hess, Clarence M. Tarzwell Jun 1941

The Feeding Habits Of Gambusia Affinis Affinis, With Special Reference To The Malaria Mosquito, Anopheles Quadrimaculatus, A.D. Hess, Clarence M. Tarzwell

United States Environmental Protection Agency: Staff Publications

The viviparous top minnow, Gambusia affinis affinis (Baird and Girard), has for many years been considered an important predator of the immature stages of mosquitoes. Various field workers have reported on the value of this species in controlling both anopheline and culicine mosquitoes, but few detailed studies have been made. Probably the most detailed of these has been that of Hildebrand (1925). His investigations were made during the summers of 1921-24 in the vicinity of Augusta, Ga., with the subspecies G. affinis holbrooki. Employing the common dipper method, he compared the densities of anopheline and culicine larvae and pupae in …


An Analysis Of Fishing In The Tva Impoundments During 1939, R. William Eschmeyer, Clarence M. Tarzwell Jan 1941

An Analysis Of Fishing In The Tva Impoundments During 1939, R. William Eschmeyer, Clarence M. Tarzwell

United States Environmental Protection Agency: Staff Publications

An inventory of fishing on Norris, a storage reservoir, was begun in 1938. The following year it was extended to Wheeler, a run-of-the-river reservoir, and to the tailwater area below Wilson Dam. This inventory, therefore, covered each of the three general types of fish habitats created by the TVA dams. This discussion is a summary of the 1939 fishing data, together with recommendations for fish management based on the creel census information. The data collected totaled 34,270 usable fishing records, representing a catch of 98,495 fishes.


Recent Advances In Biological Methods Of Sewage Treatment, H. O. Halvorson, George Savage, Edgar Piret Jan 1937

Recent Advances In Biological Methods Of Sewage Treatment, H. O. Halvorson, George Savage, Edgar Piret

Journal of the Minnesota Academy of Science

No abstract provided.