Life Sciences Commons^™

Effect Of Stubble Mulching On Number And Activity Of Earthworms, S. P. Teotia, F. L. Duley, T. M. Mccalla

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

A survey of earthworm population under different cropping systems was made under stubble mulch farming and where the residue was plowed under. The influence of earthworms on some of the important physical and biological properties of the soil was studied. Their role in the decomposition of crop residues was also determined.

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 …

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

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

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.

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

Conservation and Survey Division

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 …

The Geographic Distribution Of Azotobacter And Rhizobium Meliloti In Nebraska Soils In Relation To Certain Environmental Factors, H. B. Peterson, T. H. Goodding

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

In this investigation a survey of Nebraska soils has been made in order to determine the distribution of the aerobic nonsymbiotic and symbiotic nitrogen fixers of the genera Azotobacter and Rhizobium respectively. In connection with this survey, some of the characteristics of the soils which may bring about this distribution were studied. Up to this time practically no research has been reported on the microflora of the soils of Nebraska. Hence there is little basis for predicting the activity of these organisms under environmental conditions as they exist here. It is hoped that this work will not only supply some …

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

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

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 …