Treesearch

Spruce beetle, Dendroctonus rufipennis(Kirby) (Coleoptera: Curculionidae), poses a significant threat to mature spruce (Piceaspp.) in western North America. We evaluated 3-methylcyclohex-2-en-1-one (MCH), the primary anti-aggregation pheromone of D. rufipennis, for tree protection at 3.5 and 7 g MCH/tree (SPLAT MCH, ISCA Inc., Riverside, CA) alone and in combination with acetophenone + (E)-2-hexen-1-ol + (Z)-2-hexen-1ol (PLUS) or with linalool + β-caryophyllene + (Z)-3-hexanol (AKB). Dendroctonus rufipenniscolonization and subsequent mortality of individually treated spruce and of untreated...

Rapid ‘ōhi‘a death (ROD), caused by Ceratocystis lukuohiaand C. huliohia, severely impacts ‘ōhi‘a lehua (Metrosideros polymorpha), a keystone tree species on the Hawaiian Islands. This study examined the ability of these pathogens to colonize ‘ōhi‘a fine roots in a series of root dip experiments under in vitro conditions, focusing on the potential roles of host genetics and root tissue condition in susceptibility. The results showed that both pathogens can colonize and form fruiting bodies on fine roots; however, C. lukuohiahad greater colonization rates and produced more perithecia than...

I compile information on five rare conifer species in the White Mountains: Pinus albicaulis, P. contorta, P. ponderosa, P. jeffreyi, and Juniperus grandis.

Substantial portions of grassland are being converted to managed forest in Uruguay. Long-term paired watershed studies in other continents indicate that water yields from managed forest lands are reduced compared to grasslands. Few such studies have been conducted in South America. This paired watershed study was initiated in 2000 to determine the hydrologic impacts of changing land use from grassland to pine plantation in Uruguay. Outflow rates, water table depths, rainfall, and meteorological variables were continuously measured for a 20-year period on two adjacent watersheds, LC1 (69...

Drylands experience highly variable and potentially unpredictable interannual climate patterns which can cause post-fire seedings to occur during years with unfavorable climatic conditions. Repeated annual seeding combined with higher seeding rates show promise to improve post-wildfire restoration outcomes in drylands by increasing the likelihood that seeding occurs during a year with favorable weather conditions and overcoming potential establishment barriers from lower seeding rates when weather conditions are favorable. While combining these two techniques is an expensive proposition at...

White oak (Quercus alba L.) is an ecologically and economically important tree species, common in upland hardwood forests throughout the eastern United States (US). This study examines the population dynamics of this foundational species over the past 30 years, highlighting both range-wide and regional metrics of change. Using data from the USDA Forest Service Forest Inventory and Analysis program, we analyzed changes in age and size distributions, as well as recruitment, mortality, and growth rates. We found a significant shift towards an older, mature-dominant population, with a notable...

Ecological responses to climate change occur across vastly different time-scales, from minutes for physiological plasticity to decades or centuries for community turnover and evolutionary adaptation. Accurately predicting the range of ecosystem trajectories will require models that incorporate both fast processes that may keep pace with climate change and slower ones likely to lag behind and generate disequilibrium dynamics. However, the knowledge necessary for this integration is currently fragmented across disciplines.We develop ‘ecological acclimation’ as a unifying framework to...

The Asian longhorned beetle, Anoplophora glabripennis (ALB, Coleoptera: Cerambycidae), is a federally regulated invasive species capable of infesting several different genera of hardwood trees. Accurate knowledge of ALB’s phenology is critical for the effective implementation of management and eradication plans. We updated the ALBLT prediction model and used empirical data collected in South Carolina, USA to validate ALBLT v. 2.0. The new model largely agreed with ALB life stages found in field collections, except for late instars and pupae. We also ran the model at 8 other potentially...

Wildfire is a topic that raises much controversy in the context of forests and forest management in Europe. Fire is often viewed as a natural disaster that is harmful, yet fire is also a natural process and an important component of the disturbance regime in some forest ecosystems. A long history of land use has made it difficult to unravel the natural role of fire in European forests. Land use changes and past forestry practices have also increased fuels and fire hazard in some areas. In recent times a warming and increasingly drought-prone climate are raising concerns that fires are...

In this study, a transparent trilayer film was successfully fabricated using blade coating and hot roll lamination techniques, comprising outer layers of polylactic acid (PLA) and an inner layer of a highly shear-oriented cellulose nanocrystal (CNC)/ poly(vinyl alcohol) (PVA). The CNC/PVA coating, with a thickness ranging from 5 to 6 μm and exhibiting a high degree of CNC alignment, significantly enhanced the oxygen and carbon dioxide barrier properties, surpassing PLA by several hundred-fold. Furthermore, these laminates were formed into bags, where a fruit storage test showed that...