Pin cherry effects on Allegheny hardwood stand development

Pin cherry (Prunus pensylvanica L.) develops an early height advantage over associated species. Data from three long-term studies, extending up to 70 years after complete overstory removal, were used to evaluate the effects o f pin cherry density on associates. Survival of seedling-origin stems of bl ack cherry (Prunus serotina Ehrh.), red maple (Acer rubrum L.), and sugar m aple (Acer saccharum Marsh.) at age 15 decreased as the density of pin cher ry >1.5 m tall at age 3 increased. The regression of pin cherry with black cherry was particularly strong (R-2 = 0.632). Height of the tallest black c herry and white ash (Fraxinus americana L.) at age 15 also decreased. If th e density of pin cherry at age 3 was > 1 stem > 1.5 m tall per 0.0004 ha (h igh density), the number of black cherry fell below full stocking at age 15 . When pin cherry occurred in high density, it lived longer than when it oc curred at low density (< 1 stem > 1.5 m tall per 0.0004 ha). High pin cherr y density early in stand development delayed the time when shade-intolerant and shade-intermediate species reached a stable proportion of the total ba sal area. In the long term, pin cherry reduced stand diameter and volume gr owth, particularly of black cherry.