Use of Thinning and Prescribed Fire for Ecological Restoration of Fire-Maintained Oak Woodlands; A Rare, Historic Habitat Type in Massachusetts ForestsEPA Grant Number: U915990
Title: Use of Thinning and Prescribed Fire for Ecological Restoration of Fire-Maintained Oak Woodlands; A Rare, Historic Habitat Type in Massachusetts Forests
Investigators: Hawthorne, Brian H.
Institution: University of Massachusetts - Amherst
EPA Project Officer: Graham, Karen
Project Period: January 1, 2001 through January 1, 2003
Project Amount: $59,140
RFA: STAR Graduate Fellowships (2001) RFA Text | Recipients Lists
Research Category: Biology/Life Sciences , Ecological Indicators/Assessment/Restoration , Academic Fellowships , Fellowship - Forestry
The objective of this research project is to develop the knowledge necessary for creating an alternative type of forest opening, referred to here as woodland openings, to further increase the diversity of vegetation types and forest stand structures in Massachusetts forests. These recreation and wildlife openings are not intended as replacements for the openings currently used to provide early seral vegetation.
1. Effects on berry-producing species: The first study objective is to quantify the effects of burning and different levels of overstory cutting on berry production and berry-producing flora, primarily blueberry (Vaccinium angustifolium, V. pallidum = vaccilans, V. staminium) and huckleberry (Gaylusacchia baccata).
2. Effects on horizontal openness: I also will quantify the effects of fire and overstory cutting on the openness of forest stands and openings by measuring horizontal foliar density. Efforts will be made to involve other researchers who might have an interest in examining effects on other elements of habitat for forest-dwelling species, such as vertical complexity, deadwood, and hollow trees.
3. Effects on wildlife usage: The third objective is to quantify changes in the diversity of birds and small mammals as indicators of changes in wildlife use among the treatment groups.
4. Publication and outreach: In addition to submitting the research project results to a peer-reviewed journal, I intend to create a management guide to aid landowners in meeting combined aesthetic, recreational, and wildlife goals.
Changes in land-use and cultural practices since European settlement have drastically altered the vegetation of southern New England. Despite the reforestation of much of Massachusetts in the latter part of the 20th century, once common habitats such as fire-maintained oak woodlands are nearly nonexistent. Many private and public forest landowners share the goals of creating habitat for selected wildlife species and allowing passive recreational use of their forest, but these objectives often seem to be in conflict. For example, forest stands managed for passive recreation may favor some wildlife species, but open understories often lack forage, browse, mast, and cover for species associated with early seral stages. Conversely, openings that create early successional habitat become impassable tangles of briars and brush making most recreational uses impossible.
Pre-European inhabitants faced a similar challenge—creating open woodlands that allowed passage for hunting while providing food sources for game species. American Indians used frequent low-intensity surface fires in the spring and fall to maintain areas of open forests for easier hunting and to stimulate the production of both hard and soft mast in the chestnut/oak (Castanea dentate/Quercus spp.) forests of the Northeast (Wade, 2000). At a landscape level, these frequently burned open areas occurred within a mosaic of less frequently burned mature forests (Patterson and Sassaman, 1988).
The structure of the forests of Massachusetts has become less diverse, with fewer acres comprising early seral stages. The proportion of seedling/sapling stands to total forested area decreased from over 20 percent in 1972 to 7 percent in 1985 (Dickson and McAfee, 1988) and even further in the recently completed 1998 Forest Inventory and Analysis survey (Kittredge, personal communication). The fire-maintained woodlands that greeted the first European settlers have all but disappeared, nearly eliminating a habitat type that was once prevalent in the Northeast (Rawinski, 2000).
Evaluating techniques to support multiple management objectives such as wildlife and recreation requires knowledge of the specific effects of those techniques on key attributes of the forest. Programs such as the Coverts Project attempt to educate landowners on the improvement of habitat for selected species by the creation of early seral vegetation through sound forest management practices (Kittredge, personal communication). Unfortunately, there is little existing knowledge regarding appropriate practices for combining habitat improvement with recreational and aesthetic goals or for the creation of fire-maintained woodlands.
The primary study area will be at the Cadwell Memorial Forest (CMF or the Forest) in Pelham, Massachusetts. The Forest is on the slopes of Mt. Lincoln in the Pelham Hills between the Connecticut Valley and the Quabbin Reservoir, and is owned by the University of Massachusetts–Amherst. Cellar holes, wells, and a cemetery indicate probable agricultural use with subsequent abandonment, typical of many forests in the state. Timber operations continue on several private in-holdings. The Forest contains several plantations and experimental plots of eastern white pine (Pinus strobes), red pine (Pinus resinosa), eastern hemlock (Tsuga Canadensis), and other conifers. The remainder of the Forest is predominantly mixed oak (hardwoods), white pine (hardwoods), and red maple (Acer rubrum) swamp. Groundstory vegetation varies between sites, with dense mountain laurel (Kalmia latifolia) and other ericaceous shrubs common.
At a minimum, three sites, each approximately 2 ha in size, will be chosen at the CMF. Initial candidate sites will be selected based on data collected by a Massachusetts Agricultural Experiment Station-funded study of understory and overstory vegetation (O'Keefe, 1987). Recently completed MRES projects (Kelty, 1999; Wilson, 1999) will provide data on geology, soils, landform, shrub distribution and other parameters for the study area. Sites will be chosen to minimize variations in slope, aspect, soil, and vegetation within each site. Additional pre-treatment measurements will be made to enable final site selection, sample size determination, and preparation of cutting plans. To this end, I will measure the basal area of each overstory tree species and percent cover of understory shrubs.
A recent study of oak woodlands in Worcester, MA (Rawinsky, 2000) describes an ecosystem maintained by frequent anthropogenic brushfires that burn individual sites every 5 to 10 years. These sites support a highly diverse flora, several mammal species and many bird, butterfly, and unusual moth species, all within the city limits of Worcester. Although described as early successional, the woodlands, savannas, and grasslands remain visually open and easily traversed, supporting remarkable aesthetic and recreational features. Urban birdwatchers, berry-pickers, and hikers share the woods with wild turkeys (Meleagris gallopavo), cottontail rabbits (Sylvilagus floridanus), and the rare Harris' checkerspot butterfly (Chlosyne barrisii). In addition, one of the primary requirements of forests managed for recreation and aesthetics is a relatively open understory and low shrub layer, allowing easy passage for hikers and skiers. Many people also consider the open park-like atmosphere of woodlands and savannas to be aesthetically pleasing (Brush, 1979).
Many studies of the use of fire by pre-European inhabitants have suggested that similar woodland habitats may have resulted from frequent aboriginal burning of oak forests (Day, 1953; Pyne, 1982; Cronon, 1983; Patterson and Backman, 1988; Patterson and Sassaman, 1988; Clark and Royall, 1995; Fuller, et al., 1998). Research also has been completed on the effects of fire on oak species (Abrams, 1992), and on the use of prescribed fire for restoration of oak forests (Elliott, et al., 1999), suggesting that the use of fire may stimulate hard mast production. Several studies also have shown that fire improves the growth of certain soft-mast or berry-producing shrubs relative to other shrubs in forest understories (Swan, 1970; Patterson, unpublished data). Fire-responsive understory shrubs in Massachusetts oak forests include species such as blueberry (Vaccinium angustifolium, V. pallidum = vaccilans, V. staminium) and huckleberry (Gaylusacchia baccata). Of these, the blueberry species are likely to show the most rapid response in berry production during the first 2 years following treatments (Patterson, personal observations). Wildlife species present in Massachusetts that feed on these species include birds such as ruffed grouse (Bonasa umbellus) and ring-necked pheasants (Phasianus colchicus), and mammals such as white-tailed deer (Odocoileus virginianus), black bear (Ursus americanus), red fox (Vulpes vulpes), mice, shrews, and voles. The growth and propagation of low-bush blueberry in heathlands and the effects of burning on soil nutrients have been studied at the Maine Experiment Station (Litten, et al., 1997, Litten and Smagula, 2000). Less information is available for blueberry response to management of oak woodlands. Unpublished results from a long-term study of burning effects in oak woodlands on Cape Cod suggest that both fire and adequate light are required to stimulate berry production (Patterson, personal observation).