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Articles 13771 - 13800 of 13821

Full-Text Articles in Physical Sciences and Mathematics

Salty Seepages Can Be Productive, C V. Malcolm Jan 1961

Salty Seepages Can Be Productive, C V. Malcolm

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

MUCH has been said and written concerning the use of Paspalum vaginatum for growing on seepage areas, but the general production to be expected from seepage areas has not received much attention.

The fact is that properly handled, seepage areas can be quite productive, and can be valuable for summer grazing.


Minor Elements Can Be Overdone, L T. Jones Jan 1961

Minor Elements Can Be Overdone, L T. Jones

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

T H E term "minor elements" which is now commonly used and well understood by farmers and gardeners, refers to the five essential plant foods—copper, zinc, manganese, molybdenum and boron.

These five essential plant foods are needed by all plants in minute quantities and it is relatively easy to use them in excess of actual requirements or even in toxic amounts.

In practice this is not usually a problem with cereals and pastures. The important exception is when zinc alone is added to a cereal crop low in copper and the extra zinc accentuates the copper deficiency, and poorer yields …


Microorganisms And Soil Structure, T. M. Mccalla, F. A. Haskins Jan 1961

Microorganisms And Soil Structure, T. M. Mccalla, F. A. Haskins

Department of Agronomy and Horticulture: Faculty Publications

SUMMARY

Good stable soil structure is valuable for promoting the growth of plants and micro-organisms by permitting enhanced aeration and water penetration and by decreasing erosion under some conditions.

Micro-organisms influence water percolation through the soil. They may plug up soil pores with byproducts of growth and reduce water percolation. On the other hand, if a soil containing a large amount of microbial products is stirred and allowed to dry, then the percolation may be high.

Micro-organisms are involved in stabilizing soil structure by their products of decomposition and their cellular binding material, such as mycelia. Microorganisms differ greatly in …


The Influence Of Soil Moisture Suction And Evaporative Demand On Actual Evapotranspiration And Yield Of Alfalfa, Bozorg Bahrani May 1960

The Influence Of Soil Moisture Suction And Evaporative Demand On Actual Evapotranspiration And Yield Of Alfalfa, Bozorg Bahrani

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Evapotranspiration has been defined as the combination of evaporation of water from the soil surface and transpiration of water by vegetation. If the ground is well covered by plants, most of the water is lost by transpiration of water directly from the plant tissue, rather than by evaporation of water directly from the soil surface. The term consumptive use is synonymous with evapotranspiration.


Some Results With Nitrogen Fertiliser On Cereals At Esperance Plain Research Station, William John Toms Jan 1960

Some Results With Nitrogen Fertiliser On Cereals At Esperance Plain Research Station, William John Toms

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

ON newly-cleared land at Esperance Plain Research Station the use of sulphate of ammonia on cereals has proved profitable over a number of seasons.

The response to sulphate of ammonia varies markedly with the season.


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.


Black Spot Of Tomatoes, R F. Doepel Jan 1960

Black Spot Of Tomatoes, R F. Doepel

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

BLACK SPOT DISEASE IS THE MOST SERIOUS FOLIAGE BLIGHT OF TOMATOES IN THIS STATE. IN SEASONS FAVOURABLE TO ITS DEVELOPMENT SEVERE DEFOLIATION AND FRUIT ROTTING ARE EXPERIENCED.

IN Western Australia, black spot, which is also known as early blight and target spot, is a troublesome disease of long standing. It is caused by the fungus Alternaria solani which also attacks potatoes.


The Development Of Western Australian Sand Plain Soils For Agriculture, Richard Philip Roberts, F. L. Shier Jan 1960

The Development Of Western Australian Sand Plain Soils For Agriculture, Richard Philip Roberts, F. L. Shier

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

IN a recently published economic survey of the Australian wheat growing industry, it was reported that nearly two-thirds of the farms surveyed in Western Australia were located on lateritic "sand plain."

As a random selection was made of the eighty farms that were visited it is reasonable to conclude that a similar proportion of all the State's wheat producing farms are on that type of country.

This constitutes a remarkable change from the earlier days of wheat belt settlement when the sand plain soils were regarded as virtually useless and by-passed for development.

It is the purpose of this article …


Kimberley Research Station : A Progress Report, Department Of Agriculture, Western Australia Jan 1960

Kimberley Research Station : A Progress Report, Department Of Agriculture, Western Australia

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

INTEREST in the agricultural potential of the Kimberley region in Western Australia dates from its early exploration and settlement in the last century.

Several farming development schemes were considered for the area, but were never implemented.

This could be mainly attributable to lack of knowledge of agricultural potentialities, limitations of the local environment and ways of exploiting the local environment.

Up to the present the economy of the region is almost entirely based upon the extensive production of beef and to a lesser extent, wool.


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.


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.


Commercial Vegetable Growing In The Perth Metropolitan Region, L T. Jones Jan 1960

Commercial Vegetable Growing In The Perth Metropolitan Region, L T. Jones

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

MARKET gardening with sprinkler irrigation on deep sandy soils around Perth is really a commercial application of hydroponics or sand culture principles.

Provision of a continuous and adequate supply of nitrogen is the major problem. Peat swamps scattered among the sandy areas have higher natural fertility. However, their common problems are drainage, acidity ("sourness"), salt and various special soil deficiencies. Over-liming of acid swamps can cause new problems.


Studies In The Mulga Pastoral Zone. 1. The Grazing Of Wandarrie Grass Associations, D G. Wilcox Jan 1960

Studies In The Mulga Pastoral Zone. 1. The Grazing Of Wandarrie Grass Associations, D G. Wilcox

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

THE establishment of the Wiluna office of the North-West Branch marked the commencement of a series of investigations into the pastures of the mulga zone.

Unlike the agricultural areas where a fund of knowledge exists on the growth habits of the pastures, the pastures of this area were completely unknown.

The preliminary investigations had to be aimed at forming an understanding of the reactions of the various plants to rain, to temperature and seasonal conditions and to grazing in an area of extremely low rainfall reliability.


Bulletin No. 11: A Roadside Crisis: The Use And Abuse Of Herbicides, Richard H. Goodwin, William A. Niering Mar 1959

Bulletin No. 11: A Roadside Crisis: The Use And Abuse Of Herbicides, Richard H. Goodwin, William A. Niering

Bulletins

A proposed program for use of herbicides on town roads, to avoid present destructive practices. 13 pp.


Influence Of Various Factors On Aggregation Of Peorian Loess By Microorganisms, T. M. Mccalla, Francis A. Haskins, E. F. Frolik Jan 1957

Influence Of Various Factors On Aggregation Of Peorian Loess By Microorganisms, T. M. Mccalla, Francis A. Haskins, E. F. Frolik

Department of Agronomy and Horticulture: Faculty Publications

Soil structure is important in the attainment of adequate aeration for the aerobic microorganisms whose activities maintain such higher plant nutrients as sulfur, phosphorus, and nitrogen in a highly oxidized and thus readily available state. Good soil structure is also necessary for soil and water conservation, Under Nebraska conditions microorganisms and their decomposition products constitute a major source of soil-aggregating agents. The decomposition of crop residues and plant roots is important in the nutrition of these aggregating microorganisms. Other microorganisms, however, also utilize crop residues and plant roots, and they may decompose the aggregating agents as well, so that the …


Granular Fertiliser, C R. Hale Aug 1956

Granular Fertiliser, C R. Hale

Experimental Summaries - Plant Research

There is general agreement that granulation of fertilisers improves their physical characteristics with respect to handling, storage and distribution in the field. These physical advantages rather tan any established agronomic reason appear to be responsible for the increasing use of granular fertiliser.


Tannin Content Of English Walnuts : Thesis ..., Joseph G. Natoli Jan 1956

Tannin Content Of English Walnuts : Thesis ..., Joseph G. Natoli

University of the Pacific Theses and Dissertations

Present methods for the production of leather from animal hides still depend from the most part on the use of natural tannin extracts. During the year, 1952, the amount of natural tannin extracts used by the leather industry was 560,452,119 pounds as compared to 35,793,000 pounds of synthetic tanning materials. It is not as yet possible to produce synthetic materials as economically as the natural extracts; the result being that there is still a very great demand for natural tannin extracts. The need for finding new domestic sources of tannins is apparent when the amounts of domestic and imported extracts …


Commercial Fertilizers For Winter Wheat In Relation To The Properties Of Nebraska Soils, R. A. Olson, H. F. Rhoades Jan 1953

Commercial Fertilizers For Winter Wheat In Relation To The Properties Of Nebraska Soils, R. A. Olson, H. F. Rhoades

Nebraska Agricultural Experiment Station: Historical Research Bulletins

It is the purpose of this bulletin to report the investigations that have been made correlating soil properties and fertilization practices with yields of winter wheat. Since the success or failure of fertilization practices is so dependent on specific soil conditions, an attempt has been made here to further characterize the major soils of the different sections of the state which are devoted to wheat production and to analyze fertilizer practices and results in relation to the soil properties determined. The data are summarized for the four sections of the state designated as southeastern, east-south-central, west-south-central and western Nebraska. These …


Ionic Exchange In Soils: I. Measurement Of The Exchange Reaction By Means Of An Ion Exchange, D. A. Brown Jan 1953

Ionic Exchange In Soils: I. Measurement Of The Exchange Reaction By Means Of An Ion Exchange, D. A. Brown

Journal of the Arkansas Academy of Science

No abstract provided.


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 …


Leaflet No 1003 - The Salt Problem In The Wheat Belt, G. H. Burvill Jan 1950

Leaflet No 1003 - The Salt Problem In The Wheat Belt, G. H. Burvill

Bulletins 1 - 2999

IN the wheat belt of Western Australian bare patches in farm paddocks are often seen. Many are bare, or almost bare, because of too much salt in the soil. The excess of salt prevents the germination of seeds, or kills living plants, because it causes the water supply for germination or growth to be cut off. This salt problem is so serious in places that single farms or groups of farms have been ruined; wheat growing on them has become unprofitable.


Tertiary Coniferous Woods Of Western North America, George F. Beck Aug 1945

Tertiary Coniferous Woods Of Western North America, George F. Beck

All Faculty Scholarship for the College of the Sciences

Almost four decades have elapsed since Platen (1908), the German paleobotanist, published his report upon the fossil woods of the western United States. Since then no over-all treatment of these materials has been attempted. although Platen overlooked the Pacific Northwest with its abundance of Tertiary petrified woods. The purpose of this paper is to bring knowledge of the western coniferous woods of the Tertiary up to date. In this effort the writer recognizes that much of this information has been accumulated incidentally in the study of the Russell Petrified Forest series of central Washington, and that it is not as …


Nyssa Woods Of The Pacific-Northwest Tertiary, George F. Beck Feb 1945

Nyssa Woods Of The Pacific-Northwest Tertiary, George F. Beck

All Faculty Scholarship for the College of the Sciences

The nyssa gums are one of the modern genera of trees most certainly present among the petrified woods and forests of the Pacific Northwest. Almost every collection from the mid-Tertiary of this region contains a few specimens of typical tupelo or sour gum. These are fine-grained woods which to the unaided eye may be mistaken for conifers.


Ancient Maples Of The Central Washington Region, George F. Beck Nov 1944

Ancient Maples Of The Central Washington Region, George F. Beck

All Faculty Scholarship for the College of the Sciences

When I began work on the petrified logs of the general Vantage area some 13 years ago, it became apparent at once that maple-like woods are commonplace in the main (Vantage) raft forest and slightly less abundant in two rooted units of the Yakima Canyon. So widely do these woods range throughout the structural variations found in modern maples that little success has attended the efforts to assign them to nominal species. The extremes can readily be established but few hints exist as to the boundaries between them.


Two Newly Discovered Conifers, George F. Beck Apr 1944

Two Newly Discovered Conifers, George F. Beck

All Faculty Scholarship for the College of the Sciences

Two genera of coniferous wood, apparently not listed among the Tertiary woods of the western states, have been recognized in the Percy Train collections from Rainbow Ridge, northwestern Nevada. These two, Tsuga (hemlock) and Chamaecyparis (cedar) bring up to 14 the genera of coniferous wood more or less certainly identified from the period and area in question.


Status Of Tertiary Woods Of The Western States Representing The Juglandaceae, George F. Beck Apr 1944

Status Of Tertiary Woods Of The Western States Representing The Juglandaceae, George F. Beck

All Faculty Scholarship for the College of the Sciences

For many years there has been uncertainty concerning the generic status of some fossil leaves belonging without question to the walnut family as a whole. A review of the woods of Juglandaceae as they have appeared in Tertiary horizons of the western states has suggested which genera are present, and in what proportions their leaves (or other remains) might be expected to appear.


Nitrate Production As Affected By Grain-Crop Residues On The Surface Of The Soil, T. M. Mccalla, J. C. Russel Aug 1943

Nitrate Production As Affected By Grain-Crop Residues On The Surface Of The Soil, T. M. Mccalla, J. C. Russel

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The purpose of this bulletin is to present the data on nitrate contents and nitrate production in tests where straw or stalk residues were left on the surface through subsurface tillage, as compared with check treatments where these residues were plowed under or were absent. Nine of these tests were at Lincoln, Nebraska, and one was at the Hastings, Nebraska, Hydrological Project. Two tests were conducted in 1939, four in 1941, and four in 1942.


Preliminary Report On Subtratum Temperature Studies On Root Growth, Stanley W. Oexemann Apr 1943

Preliminary Report On Subtratum Temperature Studies On Root Growth, Stanley W. Oexemann

Journal of the Minnesota Academy of Science

No abstract provided.


Vegetation Of The Northern Part Of Cherry County, Nebraska, William L. Tolstead Jul 1942

Vegetation Of The Northern Part Of Cherry County, Nebraska, William L. Tolstead

Conservation and Survey Division: Faculty and Staff Publications

Agricultural practices in the Great Plains of North America are now in a period of adjustment from a traditional agriculture initiated by pioneer farmers to a grazing economy based upon potentialities of climate and soil. The attainment of a proper system of land use has been retarded in many localities by the lack of definite information concerning the vegetation and its indicator significance. In this study of the vegetation of Cherry County, Nebraska, the interrelations between the plants and their environments are discussed, the dominant species are described, and changes in grasslands caused by seasons, grazing, and climatic cycles are …


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 …