Phytophthora Species Detected in Two Ozark Forests with Unusual Patterns of White Oak Mortality.

Widespread decline and mortality of white oaks (Quercus alba) occurred in Missouri Ozark forests between 2011 and 2017. Symptoms included rapid crown death with bronzing of leaves, retention of dead leaves, crown dieback and thinning, and loss of large limbs within one year of death. Decline and mortality were associated with hillside drainages and fit descriptions of European oak forests predisposed to decline by pathogenic Phytophthora species.

The theory, direction, and magnitude of ecosystem fire probability as constrained by precipitation and temperature.

The effects of climate on wildland fire confronts society across a range of different ecosystems. Water and temperature affect the combustion dynamics, irrespective of whether those are associated with carbon fueled motors or ecosystems, but through different chemical, physical, and biological processes. We use an ecosystem combustion equation developed with the physical chemistry of atmospheric variables to estimate and simulate fire probability and mean fire interval (MFI).

More than Drought: Precipitation Variance, Excessive Wetness, Pathogens and the Future of the Western Edge of the Eastern Deciduous Forest.

For many regions of the Earth, anthropogenic climate change is expected to result in increasingly divergent climate extremes. However, little is known about how increasing climate variance may affect ecosystem productivity. Forest ecosystems may be particularly susceptible to this problem considering the complex organizational structure of specialized species niche adaptations.

Interactive effects of harvest and deer herbivory on the population dynamics of American ginseng.

Few demographic models for any species consider the role of multiple, interacting ecological threats. Many forest herbs are heavily browsed by white-tailed deer (Odocoileus virginianus) and a number of these are also harvested for the medicinal, floral, or horticultural trades. Previous studies of the viability of American ginseng (Panax quinquefolius) have separately examined the effects of harvesting and deer herbivory.