Physiognomy and Structure: No Data Available

Floristics: The vegetation is a closed to open canopy of conifer or mixed conifer-hardwood trees. The canopy is typically dominated by Pinus strobus. Occasionally Tsuga canadensis is mixed with the pine, or may dominate in certain areas, typically the most steep areas. Some of the stands examined by McIntosh (1950) had pine seedlings and saplings in the understory, while others were dominated by young hardwoods, such as Betula papyrifera, Populus tremuloides, Quercus alba, Quercus velutina, Ostrya virginiana, or Tilia americana. Less common conifer associates include Juniperus virginiana and Pinus banksiana. Many of the herbs and shrubs of the northern pine forests are present in these forests. Typical shrub associates include Diervilla lonicera and Vaccinium myrtilloides. Less common shrubs include Acer spicatum, Cornus canadensis, Corylus cornuta, Prunus pensylvanica, and Prunus virginiana. Typical herbs include Maianthemum canadense. Less common herb and dwarf-shrub associates may include Eurybia macrophylla (= Aster macrophyllus), Chimaphila umbellata, Gaultheria procumbens, Lycopodium obscurum, Mitchella repens, Pyrola americana (= Pyrola rotundifolia), and Trientalis borealis. Other members of the understory are found more commonly on prairies, including Amorpha canescens, Coreopsis palmata, and Dodecatheon meadia. Species typical of more southern hardwood stands include Arisaema triphyllum and Sanguinaria canadensis.

Variability in species composition in the shrub and herbaceous layers is high. This is due to the small, isolated nature of stands. No quantitative data were found on species variability, but both McIntosh (1950) and Curtis (1959) stated that it was high. This variability is due to at least two factors, both of which have to do with the small and isolated nature of examples of this community. One reason is that if a population of a northern species is extirpated from one site, it is unlikely to recolonize due to the distance to another seed source (another stand of this community) (McIntosh 1950). The second reason is that the makeup of the understory is also dependent on that of the surrounding vegetation. Because this community rarely exceeds 2 ha, some species from adjacent communities can easily invade. The identity of these species varies depending on the composition of the nearby communities.

Dynamics:  This community is apparently stable in most of its current sites. However, treefall is relatively common in this community due to the steep slopes and shallow soils. In some areas hardwoods more typical of the surrounding forest dominate the understory and may eventually replace the pines in the overstory. On most sites the conditions favor the maintenance of the community. Given the right conditions, lack of fire and no grazing, the pines have even invaded adjacent hardwood forest in a few instances.