Oak Shelterwood Establishment Harvest
Oak Shelterwood Establishment Harvest: Before
Figure 3: A before photograph of a mature, upland oak-hickory forest stand, between 80-120 years old.
This stand was prescribed a shelterwood harvest as part of a 2011 Forest Resource Management Plan to grow a new age class of oak-dominated forest. There is a lack of young, regenerating forests and an abundance of older stands in the Forest. There is limited ground cover and understory vegetation for wildlife cover, nesting habitat and food sources. The existing advanced regeneration in the midstory is shade tolerant beech, maple and birch species. The overstory is primarily oak species. Oak regeneration is declining through much of Connecticut’s Forests due to lack of natural disturbance events, less intensive timber harvesting and a shortage of even-aged forest management practices. Oak species initially require partial shade for seedling development. Once oak seedlings have developed strong root systems, they then shift focus to above-ground growth and require full sunlight to reach the overstory. There is too much shade present to perpetuate an oak-dominated ecosystem. Undesirable tree species are competing with, and crowding, the mature oaks in the overstory. This crowding decreases growth rates, tree health and acorn production. Without active management or natural disturbances, this area may transition from an upland oak forest type to one that is dominated by maple, beech and birch.
Oak Shelterwood Establishment Harvest: After
Figure 4: This is an after photograph of the same oak-dominated stand after a shelterwood establishment treatment. The harvest is designed to establish oak regeneration while maintaining a temporary, partial overstory of oak trees for continued seed production and temporary shade for establishing oak seedlings.
The stand was harvested in the winter. Winter operation promotes stump sprouting from cut trees. It also buries dormant red oak acorns in the soil, enhancing germination and establishment the following spring. The dense midstory of shade tolerant species was removed to increase sunlight to the forest floor. Additional sunlight on the ground stimulates seedling germination and vegetative growth. The remaining partial overstory of healthy oak trees will continue to provide seed sources and partial shade for establishing oak seedlings. The healthiest and most vigorous oak trees are retained for the best genetics and continued acorn production. The logging contractor utilized forest products from the site efficiently. Tree tops were lopped low to the ground to improve aesthetics, facilitate nutrient cycling, and provide coarse woody debris for wildlife habitat and cover. As this area regrows with native species, a unique habitat mix of young and old trees will diversify the surrounding, older forest age classes. This will provide beneficial habitat and food sources for a variety of early successional dependent wildlife, forest interior birds, and neotropical, migratory songbirds. The new seedlings that establish after the harvest are the future forest. These young trees will be further released, thinned and grown for another 100-120 years before the site is once again regenerated. The shelterwood treatment regenerates sun-preferring species under the temporary shelter of an overstory. It is often prescribed to perpetuate oak-dominated forest ecosystems and can also be employed to regenerate white pine forests.
Content last updated December 2020.