Climate effect on ponderosa pine radial growth varies with tree density and shrub removal

With increasing temperatures and projected changes in moisture availability for the Mediterranean climate of northern California, empirical evidence of the long-term responses of forests to climate are important for managing these ecosystems. We can assess forest treatment strategies to improve climate resilience by examining past responses to climate for both managed...

Age, allocation and availability of nonstructural carbon in mature red maple trees

• The allocation of nonstructural carbon (NSC) to growth, metabolism and storage remains poorly understood, but is critical for the prediction of stress tolerance and mortality.
• We used the radiocarbon (14C) ‘bomb spike’ as a tracer of substrate and age of carbon in stemwood NSC, CO2 emitted by stems, tree...

Growth, survival, and competitive ability of chestnut (Castanea Mill.) seedlings planted across a gradient of light levels

There has been an increased interest in tree breeding for resistance to exotic pests and pathogens, however relatively little research has focused on the reintroduction of these tree species. Understanding the durability of resistance in field settings and the field performance of improved trees is critical for successful species reintroduction. To evaluate methods for...

Early results of a chestnut planting in eastern Kentucky illustrate reintroduction challenges

This paper examines the first year results from a silvicultural study of American, hybrid (BC₂F₃) and Chinese chestnut seedlings (Castanea spp. Mill.) on the Daniel Boone National Forest in southeastern Kentucky. After one year, no significant differences in growth were found among the silvicultural...

Timing is Not Everything: Assessing the Efficacy of Pre- Versus Post-Harvest Herbicide Applications in Mitigating the Burgeoning Birch Phenomenon in Regenerating Hardwood Stands

Sweet birch (Betula lenta L.) is aggressively recruiting in temperate forest understories of the eastern United States and often dominates the post-disturbance seedling community, diminishing diversity and hindering sustainable silviculture. The type and timing of silvicultural actions affect birch recruitment via their effects on seedling...

Acid mist and soil Ca and Al alter the mineral nutrition and physiology of red spruce

We examined the effects and potential interactions of acid mist and soil solution Ca and Al treatments on foliar cation concentrations, membrane-associated Ca (mCa), ion leaching, growth, carbon exchange, and cold tolerance of red spruce (Picea rubens Sarg.) saplings. Soil solution Ca additions increased foliar Ca and Zn concentrations, and increased...

Seasonal dynamics and age of stemwood nonstructural carbohydrates in temperate forest trees

Nonstructural carbohydrate reserves support tree metabolism and growth when current photosynthates are insufficient, offering resilience in times of stress. We monitored stemwood nonstructural carbohydrate (starch and sugars) concentrations of the dominant tree species at three sites in the northeastern United States. We estimated the mean age of the starch and sugars...

Past and projected future changes in snowpack and soil frost at the Hubbard Brook Experimental Forest, New Hampshire, USA

Long-term data from the Hubbard Brook Experimental Forest in New Hampshire show that air temperature has increased by about 1 °C over the last half century. The warmer climate has caused significant declines in snow depth, snow water equivalent and snow cover duration. Paradoxically, it has been suggested that warmer air temperatures may result in colder soils...