Movement of Suspended Sediment in Streams of Forested Watersheds

My research uses tracer techniques to directly asses the source and in-stream transport of suspended sediment.  In Wangum Brook of Great Mountain Forest, I collect bi-monthly samples for suspended sediment and background water chemistry and seasonally perform tracer injection experiments.  The injection experiments are designed to simulate the movement of suspended sediment in natural stream channels under different flow conditions.  Results of these experiments illustrate the mechanisms and relative timescale of suspended sediment transport under different seasonal flow regimes.  In particular, these experiments highlight the differences in water and sediment exchange between the main stream channel and adjacent storage areas, such as pools and the streambed.  This work has further implications for the transport and streambed exchange of particle-bound nutrients and contaminants, such as phosphorus, heavy metals, and small pathogens.

I attended graduate school at Boston University from 2002-2007 and during that time I completed the majority of my field research at Great Mountain Forest.  I stayed at the Director’s cabin during the summers and set up research plots across 5 different sites at GMF.  I performed two independent research projects.  First, I assessed the impacts of the spread of the invasive plant garlic mustard (Alliaria petiolata) to forest communities, specifically measuring changes in soil nutrient cycling, microbial communities and native plant diversity and growth.  Second, I performed a large-scale field experiment to test the ecological limitations to nitrogen-fixing plants.

The M.A.P.S project was started in 1989 by the Institute for Bird Populations.  M.A.P.S. - Monitoring Avian Productivity and Survivorship- is a constant effort banding project aimed at monitoring bird populations by gathering information about PRODUCTIVITY - the ability of individual bird species to reproduce and SURVIVORSHIP of adult birds from year to year. The intent is to not only document declines as they are occurring but to attribute whether the decline is the result of adults not returning back to their breeding sites or to adults not successfully producing young on their breeding territories. Great Mountain Forest is unique in that it is one of the few old growth coniferous based forests in Connecticut, for that reason it is home to a number of northern breeders that we do not see at any of our other banding stations.  These species include Slate-colored Junco, Blackburnian Warbler, Canada Warbler and Solitary Vireo.

Turkey Release

When the first settlers arrived, Connecticut was mostly forested and turkeys were plentiful. As the land cleared, turkeys lost their habitat. This loss of habitat, combined with severe weather, and unregulated hunting, caused the turkey to disappear from the state and most of the Northeast by the early 1800’s.

As Connecticut changed from farms to forests, sportsmen attempted to reintroduce turkeys. These early attemps failed because the game farm-raised birds that were released couldn’t survive the wild.  By relocating birds captured in the wild, the  DEP Wildlife Division was able to successfully bring the wild turkey back to Connecticut.

In 1975, 22 wild turkeys were live-captured in New York, using a rocket net, and released in Northwestern Connecicut. Great Mountain Forest, was one of those release sites. Once this turkey population was established and growing, biologists captured over 300 turkeys, and released them in other areas of the state with suitable habitat. Now, turkeys are found in all of Connecticut towns.

The Great Mountain Forest Chestnut Orchard was established in 2007 by the Connecticut Chapter of the American Chestnut Foundation (CT-TACF), in collaboration with Great Mountain Forest, Housatonic Valley Regional High School, and Chubby Bunny Farms. The orchard is home to backcross chestnut trees representing the 4th of six generations of chestnuts in the American Chestnut Foundation’s backcross breeding program to breed an American chestnut highly resistant to the chestnut blight and native to Connecticut. For more information, visit www.ctacf.org

Great Mountain Forest is a critical area where surveys are being conducted to detect invasive insects and to develop an annotated checklist of wood-boring longhorned beetles in the state. Investigators from the Connecticut Agricultural Experiment Station are examining unhealthy ash trees to detect the damage of the Asian emerald ash borer, are operating baited traps to find Eurasian wood wasps, and are collecting barberries to rear adults of the European barberry fly. To obtain new distributional and host records of longhorned beetles or Cerambycidae, they are trapping adults with a variety of traps or rearing them from the dead wood of trees and shrubs. These research projects will provide valuable information on the whereabouts and habits of both unwanted alien insects and native wood-boring beetles in eastern forests.

My goal is to help develop hyperspectral remote sensing techniques to directly assess forest decline and species distribution on a landscape scale. To date this work has focused on the detection and mapping of pre-visual decline symptoms in hemlock resulting from hemlock woolly adelgid infestation. Because foliar chemistry can also be mapped with hyperspectral instruments, we are also developing decline susceptibility models that include foliar chemistry, a potentially influential factor in forest decline rates. More recently, my work has expanded to include hardwood decline, and forest species mapping. These techniques provide a much-needed tool for the early detection of new and existing stressors, and will allow forest management agencies to focus management efforts before stands are severely impacted. Most recently we have begun an effort to transfer this technology to commercially available sensors for more widespread application.

The northern forests represent the major portion of the range of eastern hemlock, Tsuga canendensis Carriere, under threat from the exotic pest, hemlock woolly adelgid, Adelges tsugae Annand or HWA.  Populations of HWA infesting eastern USA originate from southern Honshu, Japan, but over 50 years of adaptation and range expansion has led to the extensive spread of this insect from Georgia to Maine.  Current management strategies center on biological and chemical control to slow the spread of this devastating pest. There is a need for biological control agents of A. tsugae which are better adapted to these northerly climates as current imported predators from the Pacific Northwest, Japan, and China originate from temperate maritime or warm continental regions. Great Mountain Forest, with its high elevation pristine forest in USDA Plant Hardiness Zone 5b experiences some of the coldest winters in Connecticut and represents a unique opportunity to conduct adelgid-related research in an environment that parallels that of its counterparts in northern New England.  Winter survival studies of HWA and its imported ladybeetle predator, Sasajiscymnus (=Pseudosymnus) tsugae, conducted by Dr. Carole Cheah, of the Valley Laboratory, Connecticut Agricultural Experiment Station, Windsor, CT,  in cooperation with Great Mountain Forest, Corp. have been ongoing since 2001 (Fig.1). These studies have recorded the field adaptation and survival of S. tsugae on a novel prey species, balsam woolly adelgid, Adelges piceae Ratz. (BWA) (Fig. 2), and developed cold-hardy strains of S. tsugae on HWA and BWA.  In addition, plots monitoring the growth and health of healthy, uninfested hemlocks (Fig. 3) in a range of habitats at Great Mountain Forest have provided important baseline data for comparison with HWA infested stands.

Figure 1.  Overwintering cages

Figure 2.  BWA study cages

Figure 3.  Baseline site with healthy hemlocks