this study investigated the effect of sowing date and limited water allocation management for single irrigation on the grain yield of rainfed barley. the experiment was a split-split plot arranged in a randomized complete block design with three replications from 2004 to 2006 at the main station of the dryland agricultural research institute at maragheh. the treatments comprised three sowing da...

Development of wheat (Triticum spp.) is primary driven by temperature, but is also affected by other factors such as vernalization and photoperiod. Crop growth and development are often described in terms of calendar days. However, determining the development in terms of thermal time or physiological time is more accurate because it is an accumulation of the caloric energy needed for the o...

BACKGROUND The purpose of this study was to quantify the physical exertion during tree planting work and to examine the relationships between exertion, task efficiency, and productivity. METHODS Heart rate (HR) was monitored on 34 tree planters while they worked. HR data was collected for a complete working day on 19 subjects and for shorter periods of time on 15 subjects. Video of work tasks...

Management decisions grounded in ecological understanding are essential to the maintenance of a healthy urban forest. Decisions about where and what tree species to plant have both short and long-term consequences for the future function and resilience of city trees. Through the construction of a theoretical damage index, this study examines the legacy effects of a street tree planting program ...

Projected increasing demands for timber coupled with reduced harvests on public lands have led to concern among some forest policymakers regarding the adequacy of future U.S. timber supplies. One question concerns the likelihood that prevailing market incentives will induce industrial and nonindustrial private landowners to intensify forest management. We develop empirical models of historical ...

Two schools of thought exist regarding the planting of bare-root seedlings. One school favors the “pull-up” method where the seedling is pulled-up 3 to 10 cm after placing the roots in the planting hole. Although this action purportedly straightens the taproot, data are lacking to show this extra step actually improves field performance. Pulling the seedling up usually results in the root-colla...

A field inoculation method was developed to produce Meloidogyne spp. infestation sites with minimal quantities of nematode inoculum and with a reduced labor requirement compared to previous techniques. In a preseason-methyl bromidefumigated site, nematode egg suspensions were delivered at concentrations of 0 or 10(x) eggs/m of row where x = 2.12, 2.82, 3.52, or 4.22 through a drip line attached...

This study used panel data models with spatial error correlation to analyze private tree planting in the US South from 1955 to 2003. Controlling for statewide, fixed effects allows us to disentangle the effect of spatial interaction from that of state heterogeneity and omitted variables. The results show that there is significant spatial interdependence among the southern states in private tree...

A suitable planting pattern and irrigation strategy are essential for optimizing winter wheat yield and water use efficiency (WUE). The study aimed to evaluate the impact of planting pattern and irrigation frequency on grain yield and WUE of winter wheat. During the 2013-2014 and 2014-2015 winter wheat growing seasons in the North China Plain, the effects of planting patterns and irrigation fre...