A comparison of the survival and development of the seedlings of four upland oak species grown in four different understory light environments

Oak (Quercus spp.) research and management often focus on northern red oak (Quercus rubra) and assume that associated upland oaks have similar growth patterns. To test this premise, we measured the survival and development of four species of acorn-origin oak seedlings growing in four different levels of understory sunlight for 8 years. Northern red oak had better survival than black (Quercus velutina), chestnut (Quercus montana), and white oak (Quercus alba) in 5% sunlight, but none of the species exhibited much growth. In 15 and 40% sunlight, survival was equal among species, but for growth the seedlings formed two groups with chestnut/ northern red oak growing more than black/white oak. In 75% sunlight, survival was equal among species, but northern red oak grew faster than the other three species. Assuming that other oaks have growth habits similar to those of northern red oak could lead to a reduction in or the inadvertent loss of an oak species.