Physiographic analysis of witness-tree distribution (1765–1798) and present forest cover through north central Pennsylvania

Abstract

This study analyzed witness-tree data recorded from 1765 to 1798 with respect to landform in four major physiographic provinces represented through north central Pennsylvania. These data were also compared with present-day forest composition to evaluate broad changes that occurred 200 years after European settlement. In the Allegheny High Plateau, Tsugacanadensis (L.) Carr. represented 40–47% of witness trees in mountain coves and stream valleys, but only 9% on plateau tops, which comprised 45% Fagusgrandifolia Ehrh. Pinusstrobus L. represented ≤4% frequency across all landforms. The original forests of the Allegheny Mountains were dominated by mixed Quercus, Acer, Castaneadentata (Marsh.) Borkh., and Pinus and had significant T. canadensis only in stream valleys. The presettlement forests of the Allegheny Front and the Ridge and Valley provinces had a similar mix of Quercus, Pinus, Castanea, and Carya, with increased P. strobus on the more mesic sites and Pinusrigida Mill, on the xeric ridges. Comparisons of presettlement with present-day forest composition indicate a dramatic reduction of T. canadensis (32% to 4%) and F. grandifolia (33% to 12%) in the High Plateau and increases in Acer (11% to 37%), Quercusrubra L. (0% to 10%), Prunusserotina Ehrh. (1% to 6%), and Betula (5% to 10%). Other units exhibited reductions in P. strobus, P. rigida, Quercusalba L., and Carya spp. and increases in Quercusprinus L., Q. rubra, Acerrubrum L., and P. serotina. Castaneadentata had its greatest abundance on higher elevation sites in each physiographic unit, and the elimination of this species this century apparently facilitated the increase in Q. prinus and Q. rubra on ridge sites. South of the Allegheny Plateau, increases in A. rubrum, P. serotina, and other mixed-mesophytic species may be in response to fire exclusion this century. The results of this study indicate the importance of landform and physiography on presettlement forest composition as well as the dramatic changes that have occurred as a result of altered disturbance regimes following European settlement.

Patterns of exotic plant invasions in Pennsylvania’s Allegheny National Forest using intensive Forest Inventory and Analysis plots

“…The legal proclamation boundary of the ANF contains approximately 300,560 ha, of which 202,590 ha are public land ( USDA Forest Service, 2007). Average temperatures range between 20 8C in the summer and À1 8C in the winter with mean annual precipitation close to 104 cm (Cerutti, 1985;Abrams and Ruffner, 1995) and an average 100-139 days growing season (Whitney, 1990). The unglaciated plateau with elevations ranging between 300 and 720 m is a highly dissected landscape (Cerutti, 1985;Whitney, 1990) with soils derived from a variety of parent material including shale, sandstone, limestone, and chert (Abrams and Ruffner, 1995).…”

“…Average temperatures range between 20 8C in the summer and À1 8C in the winter with mean annual precipitation close to 104 cm (Cerutti, 1985;Abrams and Ruffner, 1995) and an average 100-139 days growing season (Whitney, 1990). The unglaciated plateau with elevations ranging between 300 and 720 m is a highly dissected landscape (Cerutti, 1985;Whitney, 1990) with soils derived from a variety of parent material including shale, sandstone, limestone, and chert (Abrams and Ruffner, 1995). Braun (1950) placed this region in the hemlock-white-pinenorthern hardwood type and Kü chler (1964) placed it in the hemlock-northern-hardwood forest type with the potential for oak forests.…”

The Forestry Reclamation Approach: guide to successful reforestation of mined lands

“…Historical literature and examination of sprouts and remnants of older trees indicate that American chestnut preferred rich, noncalcareous, welldrained, acidic to slightly acidic soils (pH about 4 to 6); it was a dominant component of slopes and ridgetops throughout the Appalachian region but grew poorly in wet soils (Abrams and McCay 1996, Abrams and Ruffner 1995, Braun 1950, Burke 2011, Frothingham 1912, Paillet 2002, Russell 1987, Wang and others 2013). Chestnut's abundance on the landscape varied with many factors including land use history, but it reportedly accounted for about 25 percent of the virgin timber in the southern Appalachian Mountains and more than 50 percent of the timber in some second-growth forests (Braun 1950, Buttrick 1915, Frothingham 1912.…”

Effects of light intensity on the growth and energy balance of photosystem II electron transport inQuercus albaseedlings

“…Despite its past and current dominance, oaks are facing a widespread regeneration problem, particularly on mesic or good quality sites [30]. For example, very little recruitment of new Quercus alba trees occurred during the 20th century [3,8], and there is evidence of a dramatic decline in Quercus alba forest from presettlement to the present day (e.g., [2,13,17]). Because this regeneration problem poses a serious threat to the sustainable management of oak forest, numerous ecological and silvicultural studies have been conducted in order to understand and thus solve the problem [1,27,30].…”