Composition, structure and dynamics of Dysart Woods, an old-growth mixed mesophytic forest of southeastern Ohio

• Published in: Forest ecology and management 2001-01, Vol.140 (2), p.193-213
• Main Authors: McCarthy, Brian C., Small, Christine J., Rubino, Darrin L.
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Coarse woody debris; Disturbance; Fire ecology; Forest management. Stand types and stand dynamics. Silvicultural treatments. Tending of stands. Natural regeneration; Forest succession; Forestry; Fundamental and applied biological sciences. Psychology; Old-growth; Stand dynamics; Stand types and stand dynamics. Silvicultural treatments. Tending of stands. Natural regeneration; USA, Ohio
• ISSN: 0378-1127; 1872-7042
• DOI: 10.1016/S0378-1127(00)00280-2

Dysart Woods is a 23 ha old-growth remnant of mixed mesophytic vegetation located in southeastern Ohio, USA. A designation of mixed mesophytic for this forest has historically been difficult, in part due to the abundance of white oak ( Quercus alba); however, the dominance of a variety of other hardwoods prevents a simple oak forest designation. Using two 0.35 ha plots on opposing north- and south-facing slopes, we describe the structure and composition of the overstory, understory, and soils, 30 years after their first examination. In 1970, the woods was dominated by beech ( Fagus grandifolia), white oak, and sugar maple ( Acer saccharum) — historically, the three most abundant species in this region. At that time, white oak was only present in the largest size classes, was not regenerating, and was predicted to decline in importance through succession. These patterns continue today suggesting that inferences made via overstory–understory relations in regards to forest succession are relatively robust over this time period. Beech and maple have increased in importance; white oak has decreased in importance due to mortality in the larger size classes and decreasing density due to regeneration failure. Coarse woody debris distributions correlated strongly with living stem species’ composition and structure implying an equilibrium balance. CWD volume and frequency were dominated by Quercus spp. A detailed analysis of forest health showed that all oak species were in severe decline. The oaks are in a disease decline spiral affiliated with a variety of pre-disposing and inciting factors which include their advanced age (>300 years), their large size (> 100 cm DBH), topography, chronic air pollution, drought, and Armillaria root rot fungus. Ca:Al molar ratios in the soil are also extremely low (