Nitrogen fertilizer is commonly applied to winter wheat in the High Plains to achieve moderate to high yields. Typically, anhydrous N is applied in the summer or early fall with a tillage operation. Some growers apply liquid N in the spring if winter and spring moisture are high to take advantage of higher yielding condition. Phosphate fertilizer is less frequently used on winter wheat than N f...

bruchidius fulvus allard is a biological control agent of camelthorn weed (alhagi camelorum fisch.) in birjand region. efficiency of b. fulvus for biological control of camelthorn weed was studied by separate experiments in laboratory and natural conditions based on crd in 2009. so in average, 35±1.15 and 48±1.04% of the seeds in the legumes destroyed in the spring sampling (early of may) and i...

[1] The responses of karstic aquifers to storms are often used to obtain information about aquifer geometry. In general, spring hydrographs are a function of both system geometry and recharge. However, the majority of prior work on storm pulses through karst has not studied the effect of recharge on spring hydrographs. To examine the relative importance of geometry and recharge, we break karsti...

Teaching Experience: Spring 2011 Spring 2008 Environmental Economics (14.42), MIT Econometric Theory, HKS MPA-International Development, TF for Alberto Abadie Fall 2007 Spring 2007 Spring 2006 Microeconomic Theory, HBS/HKS PhD Core, TF for Nolan Miller and Chris Avery Game Theory, HKS MPA-International Development, TF for Asim Khwaja Environmental Economics, HKS and Harvard College, TF for Robe...

Nonpoint-source pollution from agricultural activities is currently the leading cause of degradation of waterways in the United States. Applying best management practices to flood-irrigated mountain meadows may improve agricultural runoff and return flow water quality. Prior research has focused on fertilizer use for increased hay yields, while few studies have investigated the environmental im...

The effects of season and community composition as generated by livestock herbivory of differing intensity on seed species preference by Pogonomyrmex barbatus (F. Smith) were studied in a semiarid savanna on the Edward's Plateau, TX. Seasonal differences in nutrient requirements of the colony could lead to differential preferences for seeds harvested in spring and fall. Field cafeteria studies ...

Monthly estimates of 24-h milk yield were obtained on 160 spring-calving and 153 fall-calving crossbred cows containing various proportions (0, 1/4 or 1/2) of Brahman breeding, all bred to Limousin sires. Milk production was measured using weigh-suckle-weigh procedures. Interactions between crossbred group and season of calving were not significant. Across seasons, milk production rarely was af...