Issue 9

Forest Openings Grow More Fruit

Fleshy fruit, or soft mast, is a key food resource for wildlife. Unlike many other wildlife foods, fruits are available throughout the year, in seasons when other food sources may be scarce. Both fall migratory and resident winter birds depend on soft mast because it is easily obtained and high in energy. Fruit consumption has also been linked to the survival and reproductive success of several mammals.

Studies have shown a short-term increase in fruit production after natural disturbances such as storms and silvicultural practices such as regeneration cutting. Both reduce plant competition and open gaps in the forest canopy, allowing more sunlight to reach the forest floor. To effectively manage forest land to enhance fruit production, and thus wildlife habitat, we need to understand both the shortand long-term changes in production after a disturbance.

Since 1999, SRS scientists have quantified fruit abundance for 30 genera of plants in both young and mature stands of two common forest types in the Southern Appalachians- drier upland hardwoods and moister cove hardwoods. They found that much more fruit was produced in young stands than in mature forests. In the first 2 years production was similar, but during years 3 to 5 of the study, the younger stands produced 5.0 to 19.6 times more fruit. Due to the fairly stable conditions in mature stands, fruit production remained relatively low and constant.

In contrast, the dynamic process of colonization and recovery in the young, recently harvested stands caused significant changes in fruit production. Adapted to colonize disturbed sites, pioneer species such as pokeweed and blackberry became major fruit producers. Fruit production also increased in huckleberry and stump sprouts of fruit-producing trees. Flowering dogwood, American holly, Fraser magnolia, black cherry, sassafras, and blackgum all produced fruit from stump sprouts within 1 to 3 years. Overall, researchers found that young regenerated stands produce abundant fruit and are an important food source for wildlife.

Wildlife habitat can be significantly enhanced by creating or maintaining openings of young stands within forests. By selecting and leaving a few fruitproducing trees with different seasonal availability, these openings could provide an ideal food source.-LM

 

Back to: Altered Light: Regenerating Oak in Upland Hardwood Forests