Aim of study: This contribution describes a systematic search method for identifying optimum thinning regimes for beech forests (Fagus sylvatica L.) by using a combination of optimization heuristics and a simple whole stand growth prediction model. Area of study: Data to build the model come from standard and management forest inventories as well as yield tables from the Northern and Western pa...

• Motivated by the urgent need to understand how water stress-induced embolism limits the survival and recovery of plants during drought, the linkage between water-stress tolerance and xylem cavitation resistance was examined in one of the world's most drought resistant conifer genera, Callitris. • Four species were subjected to drought treatments of -5, -8 and -10 MPa for a period of 3-4 wk, a...

in order to evaluate the impact of different amounts of nitrogen fertilizer on growth and yield of two forage sorghum cultivars, a 2-year field experiment was carried out at the college of agriculture, shiraz university, shiraz, iran during 2010 and 2011 growing seasons. two factorial experiments were carried out in randomized block design with three replicates, in which the treatments included...

Questions: Is the introduced timber species Fraxinus uhdei invasive in Hawai‘i? Has logging disturbance facilitated the spread of Fraxinus and other alien species? Location: Windward Mauna Kea, island of Hawai‘i. Methods: We surveyed 29 plots which were established before selective logging of the native tree Acacia koa in 1971 to determine if Fraxinus spread beyond the borders of an existing pl...

This experiment was conducted to compare the effects of prebiotic as alternative feed additive to an antibiotic growth promoter (bacitracin methylene disalicyate) on the growth performance and morphometrical parameters of the small intestine of broiler chickens. One hundred and forty four day old broiler chicks were randomly assigned to one of three dietary treatments for 6 wk and each treatmen...

a study was carried out to examine the effect of different levels of herbal methionine and dl-methionine on the growth performance and immunocompetence of broiler chickens fed on a corn-soybean meal diet. a total of 225 old male broiler chickens (ross 308) were used as experimental samples in a completely randomized design. they were randomly assigned to 9 treatments each of 5 replicates in eve...

We examined the effect of competition on stem growth of Picea glauca and Populus tremuloides in boreal mixedwood stands during the stem exclusion stage. We combined traditional approaches of collecting competition data with dendrochronology to provide retrospective measurements of stem diameter growth. Several competition indices including stand basal area (BA), the sum of stem diameter at brea...