Natural regeneration of oak is limited during seedling establishment and growth by the amount of sunlight received through the canopy as well as the influence of competitor species. Oaks are both disturbance and advanced growth dependent, that is their slower growth requires a head start when competing with faster-growing species. When sufficient light is lacking, shade-tolerant species such as maples and beech perpetuate in low light while retarding oak seedling growth due to shady understory conditions and competition. Disturbances that reduce tree density and allow increased light to reach the forest floor can stimulate shade-intolerant species like yellow-poplar and suppress slower-growing oak seedlings. Targeted disturbances, such as midstory removal, provide partial sunlight that aids oak growth, development, and recruitment into more competitive size classes.