By Matt Drury
Article originally published in the Summer 2019 issue of A.T. Journeys Magazine.
Indigenous – Habitat/Ecosystem/Conservation
Shortleaf pine, Pinus echinata, is a widely distributed and poorly understood southern yellow pine. Growing in 22 states from southern New York to eastern Texas, it occupies the largest range of any pine in the southeastern United States. Its extensive distribution reflects it adaptability to a great variety of soil, average annual temperatures, total precipitation, and elevations (up to 3,000 feet).
Shortleaf pine is a medium-sized, native, evergreen conifer with relatively short needles and thin, flaky, black bark that becomes reddish brown with age.
Shortleaf pine has medium-thick bark which protects the tree and the dormant buds within the bole and at the base. Pines up to about 30 years of age will sprout from dormant basal buds if the crown is top-killed. It regenerates well after fire since exposed mineral soil and lack of competition facilitate seedling establishment.
There has been a dramatic decline of shortleaf pine forests and associated habitats that once covered a vast area from eastern Texas to Florida and up the eastern seaboard to New Jersey; in pure stands or in mixed shortleaf pine/oak savanna ecosystems, they grew on more than 280 million acres. Over the last 30 years, more than 50 percent of these forested acres have been lost with the most significant declines taking place east of the Mississippi River. This rapid decline can be attributed to massive pine beetle outbreaks in poorly managed stands, changes in timber management practices, altered fire regimes, disease, and land use changes.According to the Shortleaf Pine Initiative — which represents a broad range of public and private organizations, working in the shortleaf pine ecosystem: “At stake is an extraordinary diversity of cultural, ecological, and economic values centered on wildlife and recreation, water quality and a high value wood products industry. With millions of people depending on the benefits of this imperiled ecosystem, the need to develop a range-wide conservation strategy is more compelling than ever.”
Shortleaf pine seeds are an important food source for birds and small mammals. Stands of seedlings and saplings provide cover for bobwhite quail and wild turkey. Old-growth shortleaf pine provides habitat for cavity dwellers like songbirds and woodpeckers. And shortleaf pine and shortleaf pine/oak savanna ecosystems support an amazing variety of wildflowers and native grasses, providing pollinator forage for various species of bees and butterflies.
This ecological zone is only located at low elevation, typically below 2,300 feet. It occurs on exposed slopes, low hills, and ridges. Soils typically are acidic, with a pH of 4.1 to 4.3. Wind storms, tornadoes, insect infestations, and frequent wildfires are all important natural disturbance events influencing this zone — which occurs in the southern most extent of the southern Blue Ridge across South Carolina, Georgia, North Carolina, and Tennessee, extending into the southern ridge and valley and Cumberland Plateau of Tennessee and Kentucky.Along the Appalachian Trail in western North Carolina, this habitat is very restricted to low elevation areas in the Little Tennessee River and the French Broad River, including places like Lover’s Leap Trail north of Hot Springs and near the Fontana Village Resort and Fontana Lake. The forest is dominated by shortleaf pine, with less amounts of southern red oak, pitch pine, chestnut oak, scarlet oak, blackjack oak, post oak, white oak, pignut hickory, red hickory, and red maple within the shortleaf pine subtype.
Many sites with these subtypes, particularly those with no recent fire occurrences, have a dense shrub layer, this is typically dominated by ericaceous species such as mountain laurel, low bush blueberry, or bear huckleberry. Where all three subtypes have been under a more frequent prescribed burn management, the shrub layer can be quite open, with only scattered shrub occurrences. One shrub that seems to like the more frequent fire is New Jersey tea (Ceanothus americanus). Within these more open areas the herbaceous layer tends to be diverse and includes such species as fragrant goldenrod, stiff aster, little bluestem, Maryland golden-aster, Appalachian sunflower, silver plume grass, and many others. Herbaceous diversity can be sparse under the densest shrub layer and can account for fewer plant species as opposed to a more open fire-maintained habitat, which can have much more numerous species.Few rare plants have been documented within the shortleaf pine zone in the Nantahala and Pisgah National forests. Only two are currently known, Liatris squarrulosa and Thermopsis mollis. Both are herbs, are fire adapted, and flower and fruit under more open conditions.
Openings within shortleaf pine forests are generally driven by insect occurrences, in particular southern pine beetle, wind events, and fire. The last southern pine beetle infestation occurred across both forests in the late 1990s. Patch sizes can vary dramatically depending on insect outbreaks and if they are followed by fire events, which can lead to large openings. Fire is considered an important factor in maintaining this habitat with a fire return frequency as low as four years. The absence or infrequency of fire can result in more canopy oak dominance, an increase in fire intolerant trees such as red maple, and an increase in shrub density.
Find out more about the Shortleaf Pine Initiative at: shortleafpine.net