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Relationship of Eastern hemlock ( Tsuga canadensis ) to the ecology of small streams in Delaware Water Gap National Recreation Area

David P. Lemarie·John A. Young·Craig D. Snyder·Robert M. Ross·David Smith·Randy M. Bennett
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Abstract

Hemlock ravines in Delaware Water Gap National Recreation Area (DEWA) are highly valued because of their distinctive aesthetic, recreational and ecological qualities. We conducted a comparative study designed to determine the potential long-term consequences to aquatic communities of the suspected transition from hemlock-dominated forests to mixed hardwood forests as a result of hemlock woolly adelgid (HWA; Adelges tsugae) induced mortality. A landscape analysis of DEWA using Geographic Information Systems (GIs) was used to select 14 hemlock and hardwood site-pairs that were similar in topography (i.e., slope, terrain shape, aspect, light levels) and stream size (first or second order) but differed in forest composition. This paired watershed approach provided a powerful means to discern the influence of hemlock forests on stream communities. This study was designed to provide an aquatic perspective on potential losses of biological diversity should hemlock forests die.

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 40.940896° to 41.342998° latitude; -75.168339° to -74.745521° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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David P. Lemarie, John A. Young, Craig D. Snyder, Robert M. Ross, David Smith, Randy M. Bennett. 2000. Relationship of Eastern hemlock ( Tsuga canadensis ) to the ecology of small streams in Delaware Water Gap National Recreation Area. https://pubs.usgs.gov/publication/70006783

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