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The twentieth century confluence of clear-cutting, deer overabundance, and rising nitrogen deposition favored dominance by the shade-intolerant, unpalatable, and nitrogen-demanding black cherry (Prunus serotina) throughout the Allegheny Plateau of the eastern United States. The abundance of this species conferred unique and valuable ecological and economic benefits that shaped regional biodiversity and societies. Sustaining these values is increasingly difficult because black cherry, seemingly inexplicably, has experienced diminished establishment, growth, and survival in the twenty-first century. In the present article, we chronicle the change and assess underlying drivers through a literature review and new analyses. We found negative plant–soil microbial feedback loops and lowered nitrogen deposition are biologically, temporally, and geographically consistent with observed declines. The evidence suggests that black cherry dynamics are the unintended consequence of actions and policies ostensibly unconnected to forests. We suggest that these shifts are a bellwether of impending changes to forests, economies, and ownership patterns regionally and beyond. [ABSTRACT FROM AUTHOR]

Species ranges are expected to move northward with climate warming. However, species will likely encounter soil conditions that differ from their historic ranges. Black (Quercus velutina) and chestnut (Q. montana) oaks are expected to do well in climates that are hotter and drier, but it is unknown as to how they respond to soils of different geological histories. At a glaciated and nonglaciated site in northwestern Pennsylvania, we compared the growth, biomass allocation, and mycorrhizal association for black and chestnut oak seedlings at two different levels of light. On nutrient-poor, nonglaciated soils at high light levels, both species had greater growth and biomass accumulation than on nutrient-rich, glaciated soils. However, at low light levels, these responses were greatest on glaciated soils, especially for chestnut oak. Although mycorrhizal association was beneficial on nonglaciated soil at high light levels, low light levels were associated with reduced growth when compared to glaciated soils. In low light and nutrient-poor soils, mycorrhizal association may result in a carbon sink with lower net photosynthesis, as carbon for plant growth is, instead, allocated to the mycorrhizae symbiont. Variable species response to soil types indicates reduced performance for black and chestnut oak seedlings on high-quality glaciated soils especially in high light environments. [ABSTRACT FROM AUTHOR]

Anomalous dark rings found in black cherry (Prunus serotina Ehrh.) sawlogs have been anecdotally related to defoliations from cherry scallop shell moth (CSSM) (Hydria prunivorata Ferguson). Using six timber harvest sites on the Allegheny National Forest and a thinning on the Kane Experimental Forest in northwestern Pennsylvania, we documented the occurrence of dark rings in the 1970s, 1980s, and 1990s, concurrent with historical CSSM defoliations. Thirty cross-sections sampled from six Allegheny National Forest sites showed that dark rings formed on 18 sections in the 1970s, 17 sections in the 1980s, and 5 sections in the 1990s. Fourteen cross-sections had multiple (2–4) dark rings. Anatomical studies show the dark rings formed in these three decades have similar characteristics: darkened and thinner (>50 percent) fiber cell walls than normal-colored fiber cell walls. A long-term Kane Experimental Forest study was thinned in 2011–12, and dark ring frequency on recently cut stumps ranged from 48 percent to 68 percent across three replications. Dark rings in 12 of 20 cross-sections were associated with a ≥50 percent growth reduction in mean ring width during 1982–84. These results show that dark rings are associated with CSSM defoliation and that growth may be significantly reduced by defoliation. [ABSTRACT FROM AUTHOR]

An abstract of the article "Field Note: Anomalous Dark Growth Rings in Black Cherry," by Robert P. Long and colleagues is presented.