Yield tests and land valuation

Valuation of farm land depends, in the main, on farm income, which in turn depends on crop yields and farm prices. Crop yields, to go back still another step, rest largely on soil and climate. Consequently, a careful measurement of soil productivity, as determined by crop yields, is a fundamental aspect of farm valuation. Measurement of soil productivity in terms of yield differences has been hampered by the influence of management. Two farms of equal quality may produce unequal yields, not because of soil differences but because of managerial differences. In order to measure soil variation some method of controlling the management variable has to be followed. One method is to obtain a group of representative, randomized yield samples, the mean of which will represent average or typical management. Another solution, the one followed for the most part in this study, is to take yield samples of various soil conditions within an individual field, thus holding management constant

A Planetary Companion to gamma Cephei A

We report on the detection of a planetary companion in orbit around the primary star of the binary system $\gamma$ Cephei. High precision radial velocity measurements using 4 independent data sets spanning the time interval 1981--2002 reveal long-lived residual radial velocity variations superimposed on the binary orbit that are coherent in phase and amplitude with a period or 2.48 years (906 days) and a semi-amplitude of 27.5 m s$^{-1}$. We performed a careful analysis of our Ca II H & K S-index measurements, spectral line bisectors, and {\it Hipparcos} photometry. We found no significant variations in these quantities with the 906-d period. We also re-analyzed the Ca II $\lambda$8662 {\AA} measurements of Walker et al. (1992) which showed possible periodic variations with the ``planet'' period when first published. This analysis shows that periodic Ca II equivalent width variations were only present during 1986.5 -- 1992 and absent during 1981--1986.5. Furthermore, a refined period for the Ca II $\lambda$8662 {\AA} variations is 2.14 yrs, significantly less than residual radial velocity period. The most likely explanation of the residual radial velocity variations is a planetary mass companion with $M$ sin $i$ = 1.7 $M_{Jupiter}$ and an orbital semi-major axis of $a_2$ $=$ 2.13 AU. This supports the planet hypothesis for the residual radial velocity variations for $\gamma$ Cep first suggested by Walker et al. (1992). With an estimated binary orbital period of 57 years $\gamma$ Cep is the shortest period binary system in which an extrasolar planet has been found. This system may provide insights into the relationship between planetary and binary star formation.Comment: 19 pages, 15 figures, accepted in Ap. J. Includes additional data and improved orbital solutio

A Demonstration of Spectral and Spatial Interferometry at THz Frequencies

A laboratory prototype spectral/spatial interferometer has been constructed to demonstrate the feasibility of the double Fourier technique at Far Infrared (FIR) wavelengths (0.15 - 1 THz). It is planned to use this demonstrator to investigate and validate important design features and data processing methods for future astronomical FIR interferometer instruments. In building this prototype we have had to address several key technologies to provide an end-end system demonstration of this double Fourier interferometer. We report on the first results taken when viewing single slit and double slit sources at the focus of a large collimator used to simulate real sources at infinity. The performance of the prototype instrument for these specific field geometries is analyzed to compare with the observed interferometric fringes and to demonstrate image reconstruction capabilities.Comment: Accepted for publication in Applied Optic

Evaluation through laboratory studies : impact of the material to be excavated from the Illinois SSC tunnel on surface water and groundwater supplies

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The Effects of Supplementing Wet Distillers Grains Mixed With Wheat Straw to Growing Steers

A growing study compared feeding wet distillers grains, dried distillers grains, and a mix of 66% wet distillers grains and 33% wheat straw as supplements to a forage-based diet. Steers were supplemented 0, 2, 4, or 6 lb distillers grains/head daily. Wet distillers grains and dried distillers grains produced higher final body weight and dry matter intake compared to the mix. Increasing levels of distillers grains increased performance in forage based diets and wet grains mixed with straw reduced forage intake

Reducing Particle Size Enhances Chemical Treatment in Finishing Diets

Three hundred-sixty calf-fed steers were fed either treated or untreated corn stover that was previously ground through a 1-in or 3–in screen. Treated stover diets improved ADG and F:G compared to untreated. Reducing particle size improved ADG and F:G but did not influence DMI. Compared to a control diet with 5% roughage and 15 percentage units more corn, diets with 20% treated corn stover had similar F:G, ADG, DMI, and carcass quality. Up to 15% additional corn can be replaced with treated corn stover when diets contain wet distillers grains, and may be further enhanced by reducing particle size before chemical treatment

The Effects of Supplementing Wet Distillers Grains Mixed With Wheat Straw to Growing Steers

A growing study compared feeding wet distillers grains, dried distillers grains, and a mix of 66% wet distillers grains and 33% wheat straw as supplements to a forage-based diet. Steers were supplemented 0, 2, 4, or 6 lb distillers grains/head daily. Wet distillers grains and dried distillers grains produced higher final body weight and dry matter intake compared to the mix. Increasing levels of distillers grains increased performance in forage based diets and wet grains mixed with straw reduced forage intake

Reducing Particle Size Enhances Chemical Treatment in Finishing Diets

Three hundred-sixty calf-fed steers were fed either treated or untreated corn stover that was previously ground through a 1-in or 3–in screen. Treated stover diets improved ADG and F:G compared to untreated. Reducing particle size improved ADG and F:G but did not influence DMI. Compared to a control diet with 5% roughage and 15 percentage units more corn, diets with 20% treated corn stover had similar F:G, ADG, DMI, and carcass quality. Up to 15% additional corn can be replaced with treated corn stover when diets contain wet distillers grains, and may be further enhanced by reducing particle size before chemical treatment