Rare Species Guide

  Synonyms

Decachaena baccata, Andromeda baccata

  Basis for Listing

Gaylussacia baccata (black huckleberry) is a long-lived understory shrub that is common in the eastern United States but quite rare in Minnesota, where it has historically been documented from eight eastern counties as far north as Pine County (Laurentian Mixed Forest and Eastern Broadleaf Forest provinces). The occurrences are from fire-dependent forests, usually in full or partial shade. Forested habitat in this part of the state has been greatly reduced from more than a century of agricultural and urban development, and today only isolated fragments of suitable habitat remain. A large percentage of these fragments have been extensively surveyed over the last three decades, yet only five additional populations have been discovered. Furthermore, G. baccata appears to respond positively to fire, a type of disturbance that no longer occurs in these small remaining forest fragments. Lack of fire results in the buildup of shade-tolerant and fire-sensitive trees that cast more shade and create conditions where G. baccata is at a competitive disadvantage with the more shade tolerant species.

Given its limited geographic range in the state, the limited amount of remaining habitat, the small number of documented populations (despite targeted botanical surveys), the vulnerability of the known populations to successional changes, and the need for active management, Gaylussacia baccata was listed as a threatened species in 2013.

  Description

Gaylussacia baccata is a low to midsize woody shrub that forms rhizomatous colonies that can reach heights up to 1 meter (>3 ft.). The bark can be smooth or with the thin outer layer peeling and turning dark purplish gray to blackish. The leaves are elliptical to obovate, 3.0-5.5 cm (1.5-2.0 in.) long, and 1.3-2.5 cm (0.5-1.0 in.) wide. They are simple, alternate, and deciduous. They also have hairs with small resinous dots that make the leaves feel slightly sticky to the touch. The flowers are pink to reddish, 5-parted, and born on lateral racemes of 3-9 flowers. The fruit is a black-blue colored drupe, and it contains 10 hard nutlets, making them difficult to eat (Smith 2008).

Vaccinium angustifolium (lowbush blueberry) and V. myrtilloides (velvet-leaved blueberry) are two additional members of the heath family that may be found in similar habitats as G. baccata. These species differ from G. baccata in that they tend to be smaller shrubs and lack resinous yellow-orange dots on their leaves.

  Habitat

Gaylussacia baccata is found on well-drained and sandy soil or dry sandstone outcrops in fire-dependent forests. Typical associated tree species include Quercus ellipsoidalis (northern pin oak), Pinus banksiana (jack pine), or Pinus resinosa (red pine); other associated species are Vaccinium angustifolium (low blueberry), Eurybia macrophylla (big-leaved aster), Moehringia lateriflora (grove sandwort), and Pteridium aquilinum (bracken fern).

  Biology / Life History

This long-lived shrub usually flowers from mid-May to early June and is insect pollinated. The fruit matures between early August and mid-September and is animal dispersed.

Not surprisingly, this fire-dependent forest species is adapted to fire. Although new populations are founded by seeds spread in the droppings of birds and other animals, maintenance and expansion of existing populations is largely accomplished by the extensive system of long horizontal rhizomes that grow just beneath the surface of the ground (Matlack et al. 1993). Rhizomes are branching underground stems that produce both aerial stems and roots. They allow a single pioneering plant of seedling origin to spread outward by what is essentially a process of asexual or clonal reproduction. Therefore, while the above ground stems will likely be consumed by fire, the shrub vigorously re-sprouts from dormant buds on the underground rhizome (Matlack et al. 1993).  When conditions are ideal, perhaps following a fire (when competition for light or nutrients is reduced), rhizomatous growth can result in a large dense clone of perhaps 100 m² (1,000 sq. ft.) or more, with hundreds of aerial stems sharing a common root system (Harper 1995). In time, the clone may fragment, producing independent and isolated patches. Yet no matter how isolated or independent they become, all the plants originated from one seed and are still considered members of the same clone. Any given site can include many clones or just a single very old very fragmented clone.

  Conservation / Management

Management considerations for G. baccata are similar to those for other species that occur in isolated fragments of fire-dependent forests; that is, periodic fires are necessary to maintain their habitat. Without fire, certain fire-sensitive tree species will invade the understory and eventually dominate the canopy, when the older trees die. These fire-sensitive trees, typically Acer rubrum (red maple), cast more shade than the fire-dependent species they replace, typically Quercus spp. (oak) and Pinus spp. (pine). This creates conditions where G. baccata is at a competitive disadvantage with species that are more shade-tolerant; in time, G. baccata will likely disappear. For this reason, it is important to consider establishing a program of prescribed burns to simulate the natural wildfires that no longer occur.

  Best Time to Search

While one can search for this shrub from late spring through early fall, the best time to search is when the plant is fruiting, from early August until mid-September.

  Conservation Efforts in Minnesota

Gaylussacia baccata is known to occur in one state Scientific and Natural Area, one State Park, and one County Park (Ramsey County). Each of these sites has adequate regulations in place to protect against most types of disturbance; however, none of the sites have a prescribed burn plan in place.

  Authors/Revisions

Derek S. Anderson and Welby Smith (MNDNR), 2018

(Note: all content ©MNDNR)

  References and Additional Information

Harper, K. A. 1995. Effect of expanding clones of Gaylussacia baccata (black huckleberry) on species composition in sandplain grassland on Nantucket Island, Massachusetts. Bulletin of the Torrey Botanical Club 122(2):124-133.

Matlack, G. R., D. J. Gibson, and R., E. Good. 1993. Regeneration of the shrub Gaylussacia baccata and associated species after low-intensity fire in an Atlantic coastal plain forest. American Journal of Botany 80(2):119-126.

Minnesota Department of Natural Resources. 2003. Field guide to the native plant communities of Minnesota: the Laurentian mixed forest province. Ecological Land Classification Program, Minnesota County Biological Survey, and Natural Heritage and Nongame Research Program. Minnesota Department of Natural Resources, St. Paul, Minnesota. 352 pp.

Minnesota Department of Natural Resources. 2005. Field guide to the native plant communities of Minnesota: the eastern broadleaf forest province. Ecological Land Classification Program, Minnesota County Biological Survey, and Natural Heritage and Nongame Research Program. Minnesota Department of Natural Resources, St. Paul, Minnesota. 394 pp.

Smith, W. R. 2008. Trees and shrubs of Minnesota. University of Minnesota Press, Minneapolis. 703 pp.

Sorrie, B. A., A. S. Weakley, and G. C. Tucker. 2009. Gaylussacia. Pages 530-535 in Flora of North America Editorial Committee, editors. Flora of North America north of Mexico. Volume 8. Oxford University Press, New York, New York.