Treesearch

Poplars (Populus spp.) are among the fastest growing trees raised in temperate regions of the world. Testing of newly developed cultivars informs assessment of potential planting stock for local environments. Initial rooting by nine poplar clones was tested in moist and saturated soil conditions during an 18-day greenhouse experiment. Clones responded differently to soil moisture, particularly in number of roots, root distribution, and root dry mass accumulation. About 73% of cuttings planted in moist soil produced roots from callus tissue, whereas only 1% of cuttings planted in saturated...

Woodpeckers and other cavity-excavating birds worldwide are keystone species. These birds excavate their nests out of solid wood, and because their nests are often well protected against predators and the environment, other species use and compete for their old, vacant nests. The presence of cavity-excavating birds in forests has far-reaching effects on species richness and ecosystem health. Given the species’ importance, Teresa Lorenz, a research wildlife biologist with the U.S. Forest Service Pacific Northwest Research Station wanted to find out why cavity-excavating birds do not use...

Prescribed burns of winter wheat stubble and Kentucky bluegrass fields in northern Idaho and eastern Washington states (U.S.A.) were sampled using ground-, aerostat-, airplane-, and laboratory-based measurement platforms to determine emission factors, compare methods, and provide a current and comprehensive set of emissions data for air quality models, climate models, and emission inventories. Batch measurements of PM2.5, volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs), and polychlorinated dibenzodioxins/dibenzofurans (PCDDs/PCDFs), and continuous measurements of...

Ideally, variants of single-tree, group, and patch selection create new, spatially aggregated age classes and maintain a diversity of tree species and sizes in multiaged, mixed-species forests. We explored this notion in northern hardwood forests on the Menominee Nation, a forest ecosystem without the exploitive cutting history of most forests in the western Great Lakes region. Although the outcomes suggested a lack of relationship between gap characteristics and tree density, the expectations for tree regeneration were largely met: gap tree densities were >600 stems/ac and predominantly...

Historically, oak forests and woodlands intergraded with southern boreal forest, temperate mesic forest, and grassland biomes, forming complex fire-mediated relationships in the Great Lakes region of Minnesota, Wisconsin, and Michigan, USA. Variability in fire recurrence intervals allowed oaks to mix with grasses or with mesic forest species in areas with high (2–10 yr) or moderate (several decades) fire frequencies, respectively. In the southern boreal forest, oak colonization was limited by cold climate. In recent decades former savannas have been largely converted to agricultural fields...

There are more than 36,000 species of Cerambycidae (Coleoptera) recognized worldwide (see Chapter1), and they are found on all continents except Antarctica (Linsley 1959, 1961). Nearly all cerambycids are phytophagous, feeding primarily on woody plants, although some species do feed on herbaceous plants (see Chapter 3). Cerambycids develop in nearly all parts of woody plants, especially in roots, trunks, and branches, but occasionally also in seeds, pods, cones, and leaves. Inaddition, cerambycid larvae develop in nearly all major tissues in woody plants, including outer bark, inner...

Lack of suitable rearing and handling techniques has hampered research on the biology and control of many species of cerambycids that feed on host species of economic importance. Furthermore, because cerambycids spend most or all of their pre-adult life cycle inside the host plant, the biology of many is not well-known and would be difcult to study in nature. This is especially true for species with extended life cycles where adults only appear briey in the eld either annually, biannually, or less often. The development of laboratory rearing methods, either partially or completely...

We report on the results of surveillance for the salamander chytrid fungus, Batrachochytrium salamandrivorans (Bsal). Two samples from archived DNA used in a previous chytrid study in Oregon were Bsal-positive, alerting us to the first potential finding of this pathogen in North America, infecting American bullfrogs and rough-skinned newts. To confirm the finding, several additional diagnostic tests were conducted, with results that did not definitively confirm our positive finding and our gene sequencing suggested our DNA had differences from the European Bsal fungus. Insufficient sample...

Key message Mature Coffea arabica leaves were more heat tolerant than expanding leaves, longer recovery time yielded more accurate thermotolerance assessments, and photochemistry was more heat sensitive than cell membranes. Abstract Given future climate predictions of increased heatwaves in the tropics, suitable habitat to grow ecologically, economically, and socially valuable Coffea arabica L. is threatened. Accurate assessments of high temperature tolerance or thermotolerance are critical for understanding C. arabica responses to increased temperature. Thermotolerance curves of C....

Given future climate predictions of increased temperature, and frequency and intensity of heat waves in the tropics, suitable habitat to grow ecologically, economically, and socially valuable Coffea arabica is severely threatened. We investigated how leaf age and heat stress duration impact recovery from heat stress in C. arabica. Treated plants were heated in a growth chamber at 49°C for 45 or 90 min. Physiological recovery was monitored in situ using gas exchange, chlorophyll fluorescence (the ratio of variable to maximum fluorescence, FV/FM), and leaf nonstructural carbohydrate (NSC) on...