We present new results from a terrestrial laser scanner (TLS) based investigation on forest defoliation caused by the European pine sawfly (Neodiprion sertifer) in a Scots pine (Pinus sylvestris) dominated forest. The TLS results are compared with simultaneous ERS-2 Synthetic Aperture Radar (SAR) images in order to investigate the synchronous use of ALS and radar in forest change detection, and...

Defoliation by the European gypsy moth (Lymantria dispar L.) and subsequent tree mortality have been well documented in the northeastern United States. In this study we evaluate tree mortality after initial defoliation in mixed pine-hardwood stands in the southeastern United States as the range of European gypsy moth expands. In 1993, 46 mature pine-oak and pine-sweetgum stands were selected on...

High nutrient availability and defoliation generally reduce ectomycorrhizal colonization levels in trees, but it is not known how this affects the functional aspects of mycorrhizal symbiosis. It was therefore investigated whether (1) defoliation or increasing substrate N availability reduce C allocation from the plant to the fungus and N allocation from the fungus to the plant (symbiotic resour...

Understory shrubs are frequently attacked by insect herbivores. However, very little is known regarding possible interactions between light condition, defoliation (D) and fine root vitality (% live roots) and metabolic activity, and whether different plant strategies (compensation, trade-off and equilibrium) to defoliation depend on individual species light requirements. To explore the response...

Pasture degradation caused by overgrazing and inappropriate fertiliser management is a major production and environmental threat in Qinghai-Tibet Plateau. Previous research has focused on the effects of mixed nitrogen (N) and phosphorus (P) fertiliser and reduced grazing pressure on the plant community of the grassland; however, the role of P and how it interacts with various defoliation (the p...

BACKGROUND AND AIMS There is a growing concern about how forests will respond to increased herbivory associated with climate change. Carbon (C) and nitrogen (N) limitation are hypothesized to cause decreasing growth after defoliation, and eventually mortality. This study examines the effects of a natural and massive defoliation by an insect on mature trees' C and N storage, which have rarely be...

The Colorado potato beetle, Leptinotarsa decemlineata Say, is the major insect pest of potato, Solanum tuberosum L., in eastern North America and is renowned for resistance development, currently resistant to >40 insecticides worldwide. Host plant resistance may assist in delaying in resistance development to insecticides. We evaluated natural host plant resistance mechanisms (glandular trichom...

the experiment was aimed at investigating the effects of defoliation (i. e. amanipulation of source size) at different times and with different intensities on yield, grain protein content and remobilization of dry matter from shoot to grain under various levels of soil moisture and nitrogen in winter wheat. two separate field experiments were conducted simultaneously under water stress vs irrig...

studies on manipulating the source-sink relationships during postanthesis in wheat have shown inconsistent results, concluding that wheat yield could be either sink- or source-limited. most studies have reported data of grain mass as an average of all grains preventing the recognition of different sensitivities to the availability of assimilates of grains placed at different positions within th...