A Fifty Year Comparison of White Oak (Quercus alba) Growth in the Lehigh Valley and Nearby Poconos: Possible Air Pollution Effects

White oak (Quercus alba) is a dominant canopy tree of the oakchestnut subdivision of the eastern deciduous forest. We studied the annual growth increments of mature trees in the Allentown (PA) area of the lower Lehigh Valley (n = 21) and in a nearby stand in the Tannersville (PA) area of the southern Poconos (n = 36). The former has a limestone/dolomite bedrock and the latter a sandstone bedrock. The Allentown study area is 50 km. south of Tannersville; both have similar climatic conditions, and have similar response functions to yearly climatic changes. From the late 1930's to the mid 1960's, the two population means are the same (t-test, P < 0.05); by contrast, from 1965 to the present both means were different (p < 0.05). In the mid-1960s the two mean growth rates diverged—the Pocono population has decreased slightly, while the Allentown population has increased its annual growth increments. Limestone (Lehigh Valley) may effectively neutralize acid deposition, while resistant sandstones (Poconos) do so only moderately or poorly. The early 1960's are often identified with increasing acid deposition, and our study suggests a possible causal effect.

Title	A Fifty Year Comparison of White Oak (Quercus alba) Growth in the Lehigh Valley and Nearby Poconos: Possible Air Pollution Effects
Creator	Majumdar, Shyamal K.
	Rieker, D.
	Halma, J. R.
Publisher	Proceedings of the Pennsylvania Academy of Science
Academic Department	Biology
Division	Natural Sciences
Organization	Lafayette College
Date Issued	1986
Date Available	2023-06-26
Type	Article
Language	English
Bibliographic Citation	Halma, J. R., D. Rieker, and S. K. Majumdar (1986) "A Fifty Year Comparison of White Oak (Quercus alba) Growth in the Lehigh Valley and Nearby Poconos: Possible Air Pollution Effects." Proceedings of the Pennsylvania Academy of Science 60 (1): 39-42.
Standard Identifier	Handle 10385/47429b71w
Permalink	http://hdl.handle.net/10385/47429b71w
Rights Statement	In Copyright
Rights Holders	Penn State University Press