Treesearch

In October 2011, the Halloween Nor'easter produced unusually early and heavy snowfall while leaves were still on the trees, causing extensive damage throughout the northeastern United States. This storm is an example of winter weather whiplash, in which an abrupt, back-and-forth swing in winter weather affects coupled human and natural systems. Research on the social-ecological drivers and impacts of winter weather whiplash is scarce because most studies only consider meteorological causes and consequences of extreme events. In this study, we used publicly available data of snowfall...

The present study compared seasonal changes in the concentrations of calcium oxalate (CaOx) crystals and total calcium (Ca) in the foliage of red spruce (Picea rubens Sarg.), white pine (Pinus strobus L.), black oak (Quercus velutina L.), and sugar maple (Acer saccharum Marshall) trees. Samples were collected from the same four replicate trees of each species starting in June 2014 through September 2015 for a total of six times for conifers and four times for hardwoods. Calcium oxalate was extracted from tissues using a method developed in our laboratory in 2015. The purity of the extracted...

Forest managers historically sought locally sourced seed for planting to ensure that future forests were adapted to local conditions. As the climate warms, managers are increasingly seeking seed from more southerly locales. This movement of seed from outside the local seed zone, known as assisted migration, is one of several silvicultural tools being enacted to improve the resilience and adaptation of forests in the future (Williams and Dumroese 2016). A variety of strategies to implement assisted migration have been proposed (Breed et al. 2013, Havens et al. 2015, Potter and Hargrove...

Assisted migration is a promising silvicultural tool that could promote the sustainability of forest ecosystems and ecological services in the context of climate change. Assisted migration plantations, however, could be at a high risk of failure when mammalian herbivores (e.g., deer and hares) are abundant. Here, we developed an approach based on chemical content to predict the susceptibility to browsing of translocated seedlings. First, we determined which chemical compounds would be appropriate proxies of susceptibility. Second, we analyzed the chemical content of eight North American...

Quercus rubra L. is a hardwood species found throughout the eastern United States. Although climate change is projected to increase this species' suitable habitat range, current population structures and migration patterns may not be suitable to sustain future forest health. To investigate how populations respond when planted outside of their traditional ranges, we collected seeds from 22 Q. rubra populations spanning the species range and planted them in two common garden sites. Ford forest (cooler and drier) and Kellogg Forest (warmer and wetter) sites are located in Michigan's upper and...

Apostle Islands National Lakeshore (APIS) is one of the few archipelagos in Lake Superior, the largest freshwater body in the world. Sandstones deposited about 600 million years ago form the foundation for several rare features such as clay bluffs, rock ledges, coastal wetlands, and sandscapes (sandspits, cuspate forelands, tombolos). A double tombolo on Stockton Island supports a globally critically imperiled Great Lakes Barrens feature. Rare communities include boreal, krummholz, and old growth forests that support eastern hemlock, yellow birch, northern white-cedar, and Canada yew, a...

Climate change will present challenges for northern hardwood forests through the coming century. Many land managers are seeking information and resources to inform forest management activities given a wide range of potential future conditions. The field of climate adaptation is growing rapidly, with increased information available regarding the vulnerability of forests to climate change, tools for considering climate change in management planning and decision making, and management options to support adaptation to future conditions.

Foresters and other natural resource professionals are increasingly aware of the anticipated effects of climate change and adaptive management options at both the regional and local scale. Even as we gain more information about the potential impacts of climate change, however, there remain several challenges for translating large-scale and long-term climate change projections into practical action. Climate change projections and vulnerability assessments often deal with large spatial scales and general expectations. Forest managers are challenged to decide how best to apply this broad...

Beech bark disease (BBD) affects the health and quality of American beech (Fagus grandifolia). This disease complex, which spread from Nova Scotia in the late 1800s to the Great Lakes region by the early 2000s, is caused by the nonnative beech scale insect Cryptococcus fagisuga and Neonectria fungi. The scale insect feeds on living bark, altering the tissue, and allowing the fungus to enter, establish, and spread. This kills the cambium, resulting in cankers and ultimately causing mortality of many trees.

Tolerance of Dutch elm disease (DED) is the greatest challenge faced by American elm (Ulmus americana L.) populations in North America. However, adaptation to local environmental factors is also an important consideration for breeding efforts of DED-tolerant American elm because the species grows in wetlands and floodplains and was planted in urban settings across a very wide geographic range.