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...

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...

Limited water resources restrict winter wheat grain yield and quality in the Huang-Huai-Hai Plain of North China, and establishing optimal planting patterns according to crop water requirements is the key factor for achieving rational water use. In this paper, 4 planting patterns were applied, namely, uniform row (30 cm; traditional pattern), wide (40 cm)-narrow (20 cm) row, furrow (double line...

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...

Detecting local adaptation and its spatial scale is one of the most important questions of evolutionary biology. However, recognition of the effect of local selection can be challenging when there is considerable environmental variation across the distance at the whole species range. We analyzed patterns of local adaptation in emmer wheat, Triticum dicoccoides, at two spatial scales, small (int...

Results We present global planting date patterns for maize, spring wheat and winter wheat (our full, publicly available data set contains planting and harvesting dates for 19 major crops). Maize planting in the northern mid-latitudes generally occurs in April and May. Daily average air temperatures are usually c. 12–17 °C at the time of maize planting in these regions, although soil moisture of...

Corn (&a mays L.) growth has been shown to be affected by planting date and amount of residue on the soil surface. The objective of this study was to determine if the adverse effects of cool soil temperatures on early seedling growth often associated with surface residues can be overcome by planting at later dates. Corn was planted at several planting dates (late April through early June) into ...