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Articles 13951 - 13980 of 13994

Full-Text Articles in Physical Sciences and Mathematics

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 …


The Effect Of Cultivation On Certain Chemical And Physical Properties Of Some South Dakota Soils, Oscar E. Olson Jan 1937

The Effect Of Cultivation On Certain Chemical And Physical Properties Of Some South Dakota Soils, Oscar E. Olson

Electronic Theses and Dissertations

Soil Nutrient losses have followed closely in the paths of advancing frontiers in agriculture. Remedies for depletion as the result of overcropping were sought by George Washington, whose interest and investigation of soil nutrient losses probably represent the earliest attention given to land exploitation in the United States, which at the present time has become a problem of national concern. Soil losses have been attributed to a number of causes , among which are cropping, erosion, leaching, burning, and rapid oxidation of organic matter in the soil. Associated with soil nutrient losses, certain significant physical and chemical changes may occur …


Spruce In The Western Miocene, George F. Beck Nov 1936

Spruce In The Western Miocene, George F. Beck

All Faculty Scholarship for the College of the Sciences

One of the real surprises in store for us as we began to section specimens of petrified wood from the Vantage and certain other horizons in Central Washington, was the prevalence of a spruce type hardly hinted at in the leaf lists as published for the various sediments of Yakima time (upper miocene?).


Exotic Ancient Forests Of Washington, George F. Beck Apr 1935

Exotic Ancient Forests Of Washington, George F. Beck

All Faculty Scholarship for the College of the Sciences

The greatest fossil forest in the world is located within easy driving distance of the University of Washington campus in the State of Washington, near the Columbia River, east of the city of Ellensburg. Mr. George F. Beck, a member of the faculty of the Ellensburg State Normal School, and a former graduate student of the College of Forestry of the University of Washington, discovered this forest, which is now known as the Ginkgo Forest State Park. Aside from its importance from a scientific point of view, this "petrified forest," which contains a greater variety of species than any other …


The Relation Of The Native Forest Cover To The Physical And Chemical Nature Of The Soils Of The Mammoth Cave National Park Area, Sheppard Walker Aug 1933

The Relation Of The Native Forest Cover To The Physical And Chemical Nature Of The Soils Of The Mammoth Cave National Park Area, Sheppard Walker

Masters Theses & Specialist Projects

This study was undertaken for the purpose of determining the relation existing between the native forest cover and the chemical and physical properties of the soils of the Mammoth Cave National Park area. The study was suggested by certain references in the literature to a correlation existing between forest cover and the geological, chemical and physical nature of soils of this area. The recent attempt at reforestation in the Mammoth Cave National Park area renders such a study timely, and it is believed that the results reported in this paper will materially aid the Mammoth Cave National Park Commission and …


The Alkaloids, Felix F. Barre Jul 1931

The Alkaloids, Felix F. Barre

Electronic Theses and Dissertations

This thesis, presented for the degree of Bachelor of Science, provides a systematic chemical study of the alkaloids, a class of complex nitrogenous plant substances possessing basic properties. Barre opens by defining the alkaloids and surveying the various systems used to classify them, whether by natural versus artificial origin, chemical nucleus (pyridine, quinoline, or isoquinoline), volatility, or botanical family of origin, and outlines their general physical and chemical properties, including solubility, optical activity, and characteristic reactions with precipitating and color-test reagents.

The thesis details standard laboratory methods for the extraction and separation of alkaloids from plant material, including a step-by-step …


Bulletin 115 - The Value Of Windmills For Pumping Water In Western Australia, A. H. Scott Jan 1923

Bulletin 115 - The Value Of Windmills For Pumping Water In Western Australia, A. H. Scott

Bulletins 1 - 2999

It is surprising to note the dearth of up-to-date reliable information dealing with actual results of modern windmills, under working conditions, though literature on thousands of other subjects less important can usually be obtained.

In this bulletin there is presented a complete and accurate record of the amount of water pumped daily by a windmill, under actual working conditions, for a period of 14 months.


Bulletin No 81 - The Improvement Of Pastures With Notes On The Pasture Trefoils In Western Australia, E. A. Mann, D. A. Herbert Jan 1920

Bulletin No 81 - The Improvement Of Pastures With Notes On The Pasture Trefoils In Western Australia, E. A. Mann, D. A. Herbert

Bulletins 1 - 2999

Agriculture can be roughly divided for practical purposes into two large divisions, those of animal husbandry and vegetable husbandry. It is with the former that this pamphlet is chiefly concerned and its object is to contribute, it possible, in some small measure towards the problem of how to increase time stock carrying capacity of our natural pasture lands. it is unnecessary to dwell upon the importance of this question, especially in relation to the remarkable developments which are taking place in time wool-growing industry in the Southern and more coastal areas of Western Australia.


Studies Concerning The Elimination Of Experimental Error In Comparative Crop Tests, T. A. Kiesselbach Jun 1918

Studies Concerning The Elimination Of Experimental Error In Comparative Crop Tests, T. A. Kiesselbach

Nebraska Agricultural Experiment Station: Historical Research Bulletins

It is apparent that many sources of error have unconsciously entered into comparative crop yield tests. The very important matter of overcoming variation in soil conditions as a source of experimental error has been quite extensively studied and reported by various investigators during the past decade. The means suggested for reducing such error have been (1) repetition of plats and (2) correction of yields according to check plats planted to a uniform variety or treatment at stated intervals. Both methods have proved of value and a combination of both may often be used advantageously. Some danger always exists of error …