Nitrogen is one of the most important factor affecting maize (Zea mays L.) yield and income of smallholders under semiarid climates. Field experiments were conducted to investigate the impact of different N-fertilizer sources [urea, calcium ammonium nitrate (CAN), and ammonium sulfate (AS)] and rates (50, 100, 150, and 200 kg ha-1) on umber of rows ear-1 (NOR ear-1), number of seeds row-1 (NOS ...

The ability of Steinernema carpocapsae to reduce damage to seedling corn by the black cutworm, Agrotis ipsilon, in soil amended with three fertilizers (fresh cow manure, composted manure, and urea) was determined. Total nitrogen was standardized among the fertilizers at 280 kg/ha and 560 kg/ha. Black cutworm damage was assessed by the percentage of cut corn plants in small field plots. Relative...

Intensive agriculture and increased N-fertilizer use have contributed to elevated emissions of the greenhouse gases, CO2, CH4, and N2O. In this study, the exchange of the greenhouse gases, CO2, N2O, and CH4, between a Quincy fine sand (mixed, mesic Xeric Torripsamments) soil and atmosphere was measured in a sweet corn (Zea mays L.) sweet corn potato (Solanum tuberosum L.) rotation during the 20...

Long-term research aimed to determine whether narrow row spacing and harvest weed seed destruction, in combination with herbicide use, would be sufficient to drive a Lolium rigidum population to extinction. A trial was run from 1987 to 2013, with treatments including crop row spacings of 9, 18, 27 or 36 cm and crop residue burning or retention. Herbicides were applied to reflect regional practi...

Integrated nutrient management (INM) under reduced tillage practices improve soil properties and plant nitrogen (N) dynamics. The effects of urea, farmyard manure (FYM) and soybean residue (SR) under different tillage systems were evaluated in 2-year field experiments for N translocation and translocation efficiencies. Tillage systems included minimum (MT), conventional (CT) and deep (DT) tilla...

hfunlclpal and papermill wastewater sludges were ipplled to conifer and hardwood forests growing on sand soils (Entic Haplorthods, Spodic Udipsamments, and Alfic Haplorthods), In northwestern Lower Michigan where annual preclpltatio~~ averaged 765 mm/y, to Investigate the Impact of sludge on nitrate-N concentntlons In soil water and groundwater. During the first growing season after treatment, ...

In an effort to develop a chemical control strategy for the invasive Argentine ant. Linepithema humile (Mayr), in Haleakala National Park, Maxforce, which is formulated with 0.9% hydramethylnon, was used in test plots to determine the efficacy of the ant bait in the field. Initially, Maxforce was tested at 2 application rates: broadcast at 2.25 kg/ha (2 lb/ acre) and 4.5 kg/ha (4 lb/acre). Late...

a r t i c l e i n f o Accurate estimate of biomass and its changes at local to regional scales are important for a better understanding of ecosystem function, biodiversity and sustainability. In this study we explored the forest biomass prediction and dynamic monitoring from Light detection and ranging (LiDAR) waveform metrics at different key map scales. NASA's Laser Vegetation Imaging Sensor ...

Three large-scale, experimental, dispersed residual tree sites established in coastal British Columbia, Canada were measured for planted Douglas-fir tree growth and survival five to six years after planting. The dispersed trees were predominantly large diameter (60 cm+) Douglas-fir left with a range of 0% to 30% of the original forest stand basal area (0 m ha to 14 m ha). Two sites had 0%, 5% a...