John Wesley Powell worked actively for public land system
reform while a director of geographical and geological surveys in
the West from 1869 to 1894. Although this has won him acclaim as a
conservationist, the basis of Powell's linkage of reform with
scientific work is poorly understood.
A study of...
Increases in wheat production due to breeding may be reaching
a plateau. The application of N-fertilizer beyond optimum levels
leads to lodging and to an increase in tiller death. The use of
plant growth regulators (retardants) may be an answer for future
increases in production.
Experiments were conducted in 1983...
Stochastic analysis procedures have been recently applied to analyze nonlinear
dynamical systems. In this study, nonlinear responses, stochastic and/or chaotic, are
examined and interpreted from a probabilistic perspective. A multi-point-moored
ocean structural system under regular and irregular wave excitations is analytically
examined via a generalized stochastic Melnikov function and Markov...
The western cherry fruit fly, Rhagoletis indifferens
Curran, was studied to determine the suitability of the
sterile insect technique for its control. To obtain
insect material, field collection of maggots is preferred
to sifting of soil or rearing on artificial diet.
The western cherry fruit fly is strictly univoltine;
only...
Larval mortality of leafcutting bee, Megachile pacifica (Panzer)
(= rotundata (F.)), is high, usually exceeding 50%. Parasites and
predators are not a limiting factor in the survival of the progeny.
The disease chalk brood has been an important mortality factor since
1974. Inadequate food supply, pollen and nectar, may affect...