In many living trees, much of the interior of the trunk can be rotten or even hollowed out. Previously, this has been suggested to be adaptive, with microbial or animal consumption of interior wood producing a rain of nutrients to the soil beneath the tree that allows recycling of those nutrients into new growth via the trees roots. Here I propose an alternative (non-exclusive) explanation: suc...

A coupled partial diierential equation model for interaction between mountain pine beetles (MPB) and lodgepole pine is reviewed. An asymptoticòne-tree' solution is examined and time scale of the chemical response discussed. The equations are decoupled making an adiabatic assumption for MPB chemotaxis, and a `local' projection is made using the leading eigenfunction for the MPB density equation....

Growing evidence exists that aposematic and toxic prey may be included in a predator's diet when the predator experiences physiological stress. The tree sparrow Passer montanus is known to have a significant portion of aposematic and toxic ladybirds in its natural diet. Here, we present experiments testing the attack and eating rate of the tree sparrow toward the invasive aposematic harlequin l...

The objective of this study was to determine the chemical composition, in situ rumen Dry Matter (DMD) and Organic Matter Degradability (OMD48) of Apple tree leaves. In this study, Apple tree leaves were collected from the different parts of East Azerbaijan province. Chemical composition including Dry Matter (DM), Crude Protein (CP), crude Ash (Ash), ether extract, Neutral Detergent Fiber (NDF),...

Tree barks are among the less studied forest products notwithstanding their relevant physiological and protective role in tree functioning. The large diversity in structure and chemical composition of barks makes them a particularly interesting potential source of chemicals and bioproducts, at present valued in the context of biorefineries. One of the valuable components of barks is cork (phell...

Forest certification programs provide standards for multiple aspects of forest management, including the use of chemicals for mitigating competition and forest pests. The three most common programs in the United States—the American Tree Farm System, the Forest Stewardship Council, and the Sustainable Forestry Initiative—all address chemical use. To evaluate relative impacts under different cert...

The Atlantic Forest with its exuberant vegetation of high level of biodiversity is classified as one hotspot of the world. Chemical composition of leaves from native trees and underlying soils was evaluated by INAA. The predominant species Euterpe edulis, Bathysa meridionalis, Hyeronima alchorneoides, Marlierea tomentosa, Gomidesia flagellaris, and Gomidesia spectabilis belonging to the diverse...