Economic Comparison of the Undercutter and Traditional Tillage Systems for Winter Wheat-Summer Fallow Farming

Wind erosion and blowing dust are major problems for traditional tillage winter wheat-summer fallow in eastern Washington. Wind erosion reduces soil productivity and dust particulates are a major air quality concern. Conservation tillage summer fallow can reduce wind erosion markedly, but is used by relatively few farmers in the low-precipitation (less than 12 inch/year) region of the Inland Pacific Northwest. Barriers to adoption include the cost of conservation tillage implements and reluctance to change "tried and proven"traditional tillage methods. This bulletin compares economic results for the V-sweep undercutter and traditional fallow tillage systems on a case study farm located near Ritzville, WA. The farm’s eight-year average wheat yield is 46 bu/ac. Grain yields are similar for the two systems. This study shows that the undercutter method of summer fallow farming is more profitable than the traditional system on the case study farm due to slightly lower production costs. The undercutter system is eligible for conservation payments, but the traditional system is not. Receipt of these payments further strengthens the profitability advantage of the undercutter systemcapital, labor, land and management resources, type and size of machinery complement

Bankruptcy as an Occasion for Restitutionary Claims

Whether we are concerned with claims against the estate or with voidable transfers, it is essential to note that the Bankruptcy Act makes the filing of a bankruptcy petition a decisive event: a transaction occurring after the filing is likely to have consequences far different from what would have ensued if it had occurred before. The date of filing is, indeed, one of the very meanings of the word bankruptcy as it appears in the act. This point of distinction must be observed in each part of the discussion that follows. In the main, Part II concerns restitutionary principles in relation to claims against the estate; and Part III concerns certain of the trustee\u27s powers to avoid transfers by the debtor, as affected by concepts of restitution. It is undesirable to be rigorous in this division of the subject, however

Scaling Baroclinic Eddy Fluxes: Vortices and Energy Balance

The eddy heat flux generated by the statistically equilibrated baroclinic instability of a uniform, horizontal temperature gradient is studied using a two-mode f-plane quasigeostrophic model. An overview of the dependence of the eddy diffusivity D on the bottom friction κ, the deformation radius λ, the vertical variation of the large-scale flow U, and the domain size L is provided by numerical simulations at 70 different values of the two nondimensional control parameters κλ/U and L/λ. Strong, axisymmetric, well-separated baroclinic vortices dominate both the barotropic vorticity and the temperature fields. The core radius of a single vortex is significantly larger than λ but smaller than the eddy mixing length ℓ_mix. On the other hand, the typical vortex separation is comparable to ℓ_mix. Anticyclonic vortices are hot, and cyclonic vortices are cold. The motion of a single vortex is due to barotropic advection by other distant vortices, and the eddy heat flux is due to the systematic migration of hot anticyclones northward and cold cyclones southward. These features can be explained by scaling arguments and an analysis of the statistically steady energy balance. These arguments result in a relation between D and ℓ_mix. Earlier scaling theories based on coupled Kolmogorovian cascades do not account for these coherent structures and are shown to be unreliable. All of the major properties of this dilute vortex gas are exponentially sensitive to the strength of the bottom drag. As the bottom drag decreases, both the vortex cores and the vortex separation become larger. Provided that ℓ_mix remains significantly smaller than the domain size, then local mixing length arguments are applicable, and our main empirical result is ℓ_mix ≈ 4λ exp(0.3U/κλ)

RISK PERCEPTIONS AND MANAGEMENT RESPONSES: PRODUCER-GENERATED HYPOTHESES FOR RISK MODELING

Farm level risk analyses have used price and yield variability almost exclusively to represent risk. Results from a survey of 149 agricultural producers in 12 states indicate that producers consider a broader range of sources of variability in their operations. Significant differences exist among categories with respect to the importance of the sources of variability in crop and livestock production. Producers also used a variety of management responses to variability. There were significant difference among categories in the importance given to particular responses and their use of them. These results have implications for research, extension, and policy programs.Risk and Uncertainty,

The Orbital Light Curve of Aquila X-1

We obtained R- and I-band CCD photometry of the soft X-ray transient/neutron- star binary Aql X-1 in 1998 June while it was at quiescence. We find that its light curve is dominated by ellipsoidal variations, although the ellipsoidal variations are severely distorted and have unequal maxima. After we correct for the contaminating flux from a field star located only 0.46" away, the peak-to-peak amplitude of the modulation is ~0.25 mag in the R band, which requires the orbital inclination to be greater than 36 degrees. The orbital period we measure is consistent with the 18.95 h period measured by Chevalier & Ilovaisky (1998). During its outbursts the light curve of Aql X-1 becomes single humped. The outburst light curve observed by Garcia et al. (1999) agrees in phase with our quiescent light curve. We show that the single humped variation is caused by a ``reflection effect,'' that is, by heating of the side of the secondary star facing towards the neutron star.Comment: 18 manuscript pages, 7 figures; accepted by A