Oak decline, the precipitous mortality of mature oak trees, has been a chronic problem in xeric oak ecosystems and is reaching unprecedented levels in red oak group (Quercus section Lobatae) species in the Ozark Highlands. The high rates of mortality are leading to rapid changes in species composition, forest structure, and related changes in fire risk, insect populations, and colonization patt...

Survival analysis methodologies provide novel approaches for forest mortality analysis that may aid in detecting, monitoring, and mitigating of large-scale forest health issues. This study examined survivor analysis for evaluating a regional forest health issue - Missouri oak decline. With a statewide Missouri forest inventory, log-rank tests of the effects of covariates on the survivor functio...

this study was aimed to assess the causes of the structural decline in the renewal rate of apristine oak forest close to rome (central italy) by analyzing long-term measurements of the water budget in open and fenced areas. despite dry climate conditions in the area, long-term soil moisture measurements at 100 cm soil depth indicated that an enough large amount of water is available to oaks dur...

one of the most visible aspects of a forest stand structure is the spatial patterns of trees. competition affects on forest structure and its understanding is important, when the purpose of forest management is to imitate the dynamic of natural ecosystems. for this purpose, an unmanaged intact forest was selected with 26 hectares area. all chestnut leaf oak (quercus castaneifolia) trees with a ...

Black oak (Quercus velutina Lam.) and scarlet oak (Quercus coccinea Muenchh.)—two major components (44% of total stand basal area) of upland oak forests—are suffering severe decline and mortality in the Ozark Highlands, Missouri. However, factors influencing their survival (mortality) are not well understood. In this study we quantified how stand and tree-level predisposing factors are associat...

Acute Oak Decline (AOD) is a new condition affecting both species of native oak, Quercus robur and Quercus petraea, in Great Britain. The decline is characterised by a distinctive set of externally visible stem symptoms; bark cracks that “weep” dark exudate are found above necrotic lesions in the inner bark. Emergence holes of the buprestid beetle, Agrilus biguttatus are often also seen on the ...

Acute Oak Decline (AOD) is a decline-disease that has distinctive symptoms and poses serious threat to oak. Our understanding of the causal factors AOD remains poor but it likely multiple biotic abiotic contribute deterioration in oak condition. There evidence indications above-ground tree health status are frequently reflected below-ground roots associated ectomycorrhizal (ECM) fungal communit...

In the Ozark Mountains of northern Arkansas and southern Missouri, an oak decline event, coupled with epidemic populations of red oak borer (Enaphalodes rufulus Haldeman), has resulted in extensive red oak (Quercus spp., section Lobatae) mortality. Twenty-four northern red oak trees, Quercus rubra L., infested with red oak borer, were felled in the Ozark National Forest between March 2002 and J...

Oak forests throughout the world are in a state of decline due to lack of oak seedling recruitment to larger size classes. Much of this recruitment decline has been attributed to changes in ecosystem disturbance regimes that have led to increased competition from other species. The Midwest Driftless Area forests in the United States are currently dominated by large oak trees of three species: Q...