ABSTRACT- To study the effect of tree roots on increasing water infiltration in soil and also to determine and assess the coefficients of different infiltration models, some infiltration tests were performed in three tree plantation areas in Badjgah, Fars province with different soil textures (clay loam for pear plantation, sandy loam for grape plantation, loamy sand for pine trees). In each pl...

Several studies suggest that some bark beetle like to attack large trees. The invasive red turpentine beetle (RTB), Dendroctonus valens LeConte, one of the most destructive forest pests in China, is known to exhibit this behavior. Our previous study demonstrated that RTBs preferred to attack large-diameter trees (diameter at breast height, DBH ≥30 cm) over small-diameter trees (DBH ≤10 cm) in t...

BACKGROUND Tests were conducted on two insecticides (carbaryl and bifenthrin) for excluding subcortical beetles (Coleoptera: Curculionidae and Cerambycidae) from loblolly pine trees (Pinus taeda L.). Two trap designs (single- and double-pane windows) and two trapping heights (1.5 and 4 m) were also evaluated for maximizing beetle catches. RESULTS In July 2009, 15 loblolly pine trees were doub...

Individual-tree models of five-year basal area growth were developed for jack pine (Pinus banksiana Lamb.) and black spruce (Picea mariana (Mill.) BSP) in northern Ontario. Tree growth data were collected from long-term permanent plots of pure and mixed stands of the two species. The models were fitted using mixed model methods due to correlated remeasurements of tree growth over time. Since th...

Forests of Iran located on the Southern border of the Caspian Sea cover 1.9 million hectares. The Caspian forests are divided into four separate forestry areas. One of these being Guilan influx area with total area of 565000 hectares. About 30 to 40 percent of Guilan province forests are suitable to short rotation forestry for afforestation. Slash pine (Pinus elliottii) is one of the main exo...

Individual lodgepolepines(Pinus contorta)were fertilizedwithureaatnitrogen(N) inputs equivalent to 0, 315, or 630 kg/ha. Four months after application of the fertilizer, inner bark tissue N concentrations were signiÞcantly higher in the trees that had received the low dose (315 kg/ha) fertilization treatment than in the control trees; trees that had received the high-dose treatment (630 kg/ha) ...

Individual lodgepole pines (Pinus contorta) were fertilized with urea at nitrogen (N) inputs equivalent to 0, 315, or 630 kg/ha. Four months after application of the fertilizer, inner bark tissue N concentrations were significantly higher in the trees that had received the low dose (315 kg/ha) fertilization treatment than in the control trees; trees that had received the high-dose treatment (63...

Native Monterey pine (Pinus radiata D. Don) forests are currently found at three disjunct locations in coastal California and on two islands off the coast of Mexico. The mainland forests comprise, in total, approximately 4,500 ha (11), whereas the two island populations are limited to 150 ha on Cedros Island and fewer than 400 trees on Guadalupe Island (28). Collectively, these populations are ...

To study the effects of wildfire on population genetics of a wind pollinated and wind dispersed tree, we have analyzed the genetic structure of a post-fire, naturally regenerating seedling population of Pinus halepensis Miller, on Mt. Carmel, Israel. We tested the existence of spatial genetic structure, which is expected due to the special spatial demographic structure of the post-fire seedling...

Scatter hoarders are not able to defend their caches. A longer hoarding distance combined with lower cache density can reduce cache losses but increase the costs of hoarding and retrieving. Scatter hoarders arrange their cache density to achieve an optimal balance between hoarding costs and main cache losses. We conducted systematic cache sampling investigations to estimate the effects of food ...