What About Continuous Corn?

Interest in continuous corn in Iowa has been g rowing for several years. And increasing numbers of farmers have been trying it out on their own. Here\u27s a report on the results of our Iowa tests with continuous corn

Principles and methods of wind-erosion control in Iowa

Wind erosion in Iowa has been increasing in frequency and intensity with the increase in acreage of row crops and consequent increase in fall-plowed acres. This erosion has attracted widespread attention because blowing dust has created a hazard to health and safety. This bulletin is a report of research conducted in areas where wind erosion has been a problem for many years and the application of the findings in Iowa.https://lib.dr.iastate.edu/specialreports/1058/thumbnail.jp

Using Rainfall Records as Guides to Predict Yields of Cotton on Drylands of the High and Rolling Plains of Texas.

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The influence of nitrogen and phosphorus ferilization on nutrient status and profitability of Bromegrass on Ida soils

This study was undertaken to determine the profitability and the feasibility of fertilizing bromegrass for grazing in the Monona-Ida-Hamburg soil association area. This area is well adapted to growing forage crops. Because of the high content of calcium and potassium, alfalfa grows well if phosphorus is applied. Bromegrass is able in some way to get nitrogen from alfalfa, and the two crops grow well together. The bloat danger in pasturing alfalfa or bromegrass-alfalfa mixtures, however, is well known to cattlemen in the area. Many believe the cost of nitrogen fertilizer to maintain productivity of bromegrass pastures is less than the cost of losses from bloat on bromegrass-alfalfa pastures. The profitability of fertilizing bromegrass stands is examined in Part I of the study. The feasibility is examined in Part II. In Part I, returns at three levels of nitrogen cost and beef price and at three conversion ratios of forage to beef are calculated on the basis of experimental yields

Soils Survey of Spink County South Dakota

This soil survey report with its accompanying map presents information about the soils, crops, and agriculture of Spink County. It also deals briefly with such related topics as topography and cultural features. This soil survey is designed to meet the needs of a wide variety of readers. The following paragraphs indicate the sections of interest to persons concerned with specific tracts of land, to those concerned with the county as a whole, and to students and teachers of soil science and related agricultural subjects

A New Independent Limit on the Cosmological Constant/Dark Energy from the Relativistic Bending of Light by Galaxies and Clusters of Galaxies

We derive new limits on the value of the cosmological constant, $\Lambda$, based on the Einstein bending of light by systems where the lens is a distant galaxy or a cluster of galaxies. We use an amended lens equation in which the contribution of $\Lambda$ to the Einstein deflection angle is taken into account and use observations of Einstein radii around several lens systems. We use in our calculations a Schwarzschild-de Sitter vacuole exactly matched into a Friedmann-Robertson-Walker background and show that a $\Lambda$-contribution term appears in the deflection angle within the lens equation. We find that the contribution of the $\Lambda$-term to the bending angle is larger than the second-order term for many lens systems. Using these observations of bending angles, we derive new limits on the value of $\Lambda$. These limits constitute the best observational upper bound on $\Lambda$ after cosmological constraints and are only two orders of magnitude away from the value determined by those cosmological constraints.Comment: 5 pages, 1 figure, matches version published in MNRA

High field magnetic resonant properties of beta'-(ET)2SF5CF2SO3

A systematic electron spin resonance (ESR) investigation of the low temperature regime for the (ET)2SF5CF2SO3 system was performed in the frequency range of ~200-700 GHz, using backward wave oscillator sources, and at fields up to 25 T. Newly acquired access to the high frequency and fields shows experimental ESR results in agreement with the nuclear magnetic resonance (NMR) investigation, revealing evidence that the transition seen at 20 K is not of conventional spin-Peierls order. A significant change of the spin resonance spectrum in beta'-(ET)2SF5CF2SO3 at low temperatures, indicates a transition into a three-dimensional-antiferromagnetic (3D AFM) phase.Comment: 4 pages, 7 figures, minor grammatical change

A minimal set of invariants as a systematic approach to higher order gravity models: Physical and Cosmological Constraints

We compare higher order gravity models to observational constraints from magnitude-redshift supernova data, distance to the last scattering surface of the CMB, and Baryon Acoustic Oscillations. We follow a recently proposed systematic approach to higher order gravity models based on minimal sets of curvature invariants, and select models that pass some physical acceptability conditions (free of ghost instabilities, real and positive propagation speeds, and free of separatrices). Models that satisfy these physical and observational constraints are found in this analysis and do provide fits to the data that are very close to those of the LCDM concordance model. However, we find that the limitation of the models considered here comes from the presence of superluminal mode propagations for the constrained parameter space of the models.Comment: 12 pages, 6 figure