Persistence and abundance of species is determined by habitat availability and the ability to disperse and colonize habitats at contrasting spatial scales. Favourable habitat fragments are also heterogeneous in quality, providing differing opportunities for establishment and affecting the population dynamics of a species. Based on these principles, we suggest that the presence and abundance of ...

A combination of wildfires and defoliating insect outbreaks play an important role in the natural successional dynamics North American boreal mixedwood forests, which, long term, change post-disturbance composition structure forest stands. After stand-replacing disturbances (mainly wildfires), early hardwoods typically dominate affected areas. Provided enough time following disturbances, increa...

It is important to develop best management practices for novel tall fescue systems in the southern Great Plains of North America, especially since cool-season perennials are not well known or commonly utilized in this region. This review paper summarizes the research activities in this region of the southern Great Plains for developing new perennial tall fescue systems (establishment, legume-gr...

Seedling regeneration and morphology of Oregon grape (Berberis nervosa Pursh) and salal (Gaultheria shallon Pursh) were studied in thinned and unthinned Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) stands in the central Coast Range, Oregon. Aboveand below-ground growth of both species were significantly and negatively correlated with stand density. Oregon grape appears to have less potent...

There is growing interest in using switchgrass (Panicum virgatum L.) as a biofuel crop and for its potential to sequester carbon. However, there are limited data on the establishment success of this species when grown as a forest intercrop in coastal plain settings of the U.S. Southeast. Therefore, we studied establishment success of switchgrass within experimental intercropped plots and in pur...

Decision support systems can help improving nutrient management in agricultural and forest ecosystems. We suggest that the practical components of nutrient management are 1) Diagnosis, 2) Prediction, 3) Economic analysis, and 4) Recommendations. Nutrient management and agronomic information for perennial crops such as peach palm (Bactris gasipaes Kunth) revealed important differences from annua...

Aboveground competition is often argued to be the main process determining patterns of natural forest regeneration. However, the theory of multiple resource limitation suggests that seedling performance also depends on belowground competition and, thus, that their relative influence is of fundamental importance. Two approaches were used to address the relative importance of aboveand below-groun...

We investigated the effect of fire severity and environmental conditions on conifer tree regeneration 11 years after an autumn wildfire in the western Oregon Cascade Range. Conifer tree seedlings, including those of Pseudotsuga menziesii, established promptly and at high densities following fire, in contrast to long establishment periods documented for many other sites. P. menziesii, Tsuga hete...

With regard to desired natural regeneration establishment that it is the goal of selection systems. The role of tree and group selection silvicultural systems on the quantity and quality of natural regeneration was conducted at four site of forest. First, 100 circular sample plots has been selected by use of random systematic inventory. Then into the each plots nine micro-plots defined. The res...