Little Trees, Big Benefits

By Bob DeWitt | August 2, 2003
From Missouri Conservationist: Aug 2003

Because they live so much longer than people, we often perceive trees as being practically immortal. However, trees also follow the same cycle of birth, growth, reproduction and death that governs all living things. Whether a forest is managed or left alone, the changes it goes through during its lifetime are referred to as succession.

Trees are valuable at every age, but their ability to provide wildlife habitat varies greatly throughout their life cycle. Mature trees shade the ground and provide little cover for wildlife species. Whether the result of natural disturbance or human harvest, the removal of mature trees from a forest allows the sun to reach the soil surface, stimulating a flush of new vegetation. This new growth contains grasses, legumes and forbs, but the dominant group that will spring up in a Missouri oak-hickory forest is woody plants.

These plants may sprout from seed germinating under the conditions provided by the new forest opening, or they may be existing sprouts that have languished in the shade of the mature trees. They may sprout from shoots that come from dormant buds on the stumps and roots of the trees that were removed. Whatever the source of the new growth, a vigorous young forest normally appears in a forest opening within the first growing season or two after the disturbance takes place.

The period of vigorous regrowth and renewal of a forest is called regeneration. Regeneration conditions usually last between 10 and 20 years under average forest conditions. The regeneration forest may not be as aesthetically attractive as the cathedral-like setting of mature trees that previously occupied the site, but what a haven it provides for wildlife!

No other stage in the life of a forest provides so much for so many different species of animals. The abundant, low-growing foliage provides browse for mammals and insects during the growing season. The proliferation of insects, in turn, becomes a high-protein food source for many bird species during their brooding period. The numerous herbaceous plants provide seeds and fruit to sustain wildlife through the fall and winter, as well as nesting and protective cover.

In contrast to abandoned cropland or pasture that is being reclaimed by woody plants, forest openings are used less frequently by less desirable animal species, such as cowbirds that compete with neo-tropical migrant songbirds. Nor can many introduced foreign plant species, such as dense, sod-forming grasses, successfully compete with native vegetation in forest openings.

Wildlife species that prefer areas of forest regeneration include popular game species like quail, turkey and deer, as well as bobcats, flying squirrels and Indiana bats. Numerous songbirds thrive in new forest openings. These include the great crested flycatcher, chestnut sided warbler and Carolina wren.

Ruffed grouse also thrive in forest regeneration areas. Sportsman, birdwatchers and hikers are always thrilled to encounter this handsome woodland partridge with its distinctive mating drumming and whirring flight. Wildfires, heavy woodland grazing, forest clearing and market hunting nearly caused the extinction of ruffed grouse in Missouri by the mid 1900s, prompting the Conservation Department to initiate a grouse restoration program in 1959. To date, more than 6,000 grouse have been released in more than half of Missouri's counties. Restocking alone is not enough to ensure success, however. The abundance of adequate woodland habitat in a regeneration condition is also critical.

A large percentage of Missouri's woodlands were last harvested between the late 1800s and the early 1900s. Now, many of Missouri's forests are mature. Although oak-hickory forest can persist in a continually maturing condition for two to three centuries, many habitat benefits of a forest are often lost after just two or three decades of maturation. A trend toward reduced forest harvesting has created a deficit of the desired regeneration habitat. Maintaining an adequate amount of our state's forests in the regenerative condition requires harvesting timber.

The River Hills Forest Habitat Project was recently formed to increase the numbers of ruffed grouse in east-central Missouri. The partnership promotes early forest successional habitat, the lack of which is a limiting factor in the ruffed grouse's population. The project is a joint effort of the National and Missouri chapters of the Ruffed Grouse Society, the Audubon Society of Missouri, the National Wild Turkey Federation and the Missouri Department of Conservation. The project targets portions of Warren, Montgomery and Callaway counties that lie north of the Missouri River, south of I-70 and East of Highway 54. Thanks to a grouse restoration program that was completed in this area in the 1970s, the target area contains some of the last significant populations of ruffed grouse in the state.

A common forest management standard is to have 10 percent of the forest cover in a regeneration condition. In most of the project's target area, less than 1 percent of the forest is in suitable condition. To encourage landowners in this area to consider forest regeneration as a component of their overall land management efforts, the partnership offers free technical assistance from wildlife biologists and foresters. It also recommends or provides qualified forestry contractors to implement the proper practices for landowners.

High-priority habitat projects, especially those on property adjoining state conservation areas where forest regeneration is emphasized, such as Daniel Boone and Little Lost Creek conservation areas, are eligible for up to 90 percent cost reduction. Reduced cost for participating landowners is made possible through a matching fund set up by the Ruffed Grouse Society, the National Wild Turkey Federation and the Conservation Department. Additional partnerships and matching funds are continually being pursued.

Practices that can be implemented to provide young forest habitat include woodland improvement and woody edge enhancement. Woodland improvement consists mainly of eliminating undesirable tree species (from a timber or wildlife perspective) in a forest stand and providing conditions more conducive to regenerating oak hardwoods. Woody edge enhancement consists primarily of creating small openings in large blocks of mature forest that will stimulate forest regeneration. As part of a landowner's management regime, either or both of the practices provide a multitude of wildlife benefits.

Landowners in the project area, or in other parts of the state, wanting to know more about including forest regeneration in the management of their forest land, should contact their regional Conservation Department office. The River Hills Forest Habitat Project is coordinated through the Central Region office in Columbia and can be reached at (573) 884-6861.

This Issue's Staff

Editor - Tom Cwynar
Managing Editor - Bryan Hendricks
Art Editor - Dickson Stauffer
Designer - Les Fortenberry
Artist - Dave Besenger
Artist - Mark Raithel
Photographer - Jim Rathert
Photographer - Cliff White
Staff Writer - Jim Low
Staff Writer - Joan McKee
Circulation - Laura Scheuler