Physiognomy and Structure: No Data Available

Floristics: The canopy is strongly dominated by Pinus palustris, which generally accounts for over 75% of the total cover. Other canopy species may include Liquidambar styraciflua, Nyssa sylvatica, Acer rubrum, Pinus taeda, and possibly Pinus elliottii var. elliottii from nearby plantations. Magnolia virginiana has also been included as a component (Turner et al. 1999). Shrubs and shrubby vines are frequently dense, and include Morella cerifera (= Myrica cerifera), Morella caroliniensis (= Myrica heterophylla), Persea palustris, Smilax bona-nox, Smilax laurifolia, Smilax pumila, Smilax rotundifolia, and Rubus spp. Where the shrubs and canopy are very dense, the ground cover is suppressed and has a cover of approximately 5%; in thinned plantations, the more open canopies allow a low-diversity ground cover of 30% or less. The lower strata in this situation are dominated by the short shrubs Hypericum fasciculatum and Hypericum hypericoides ssp. hypericoides, as well as Hypericum mutilum, with some Viola spp. and occasional Carex spp. and Scleria spp. Although currently not above-ground constituents of this community, many heliophytic taxa such as Xyris, Rhexia, Ctenium, and Rhynchospora still persist in a seed/root bank and readily come back with the onset of prescribed burning (R. Stewart pers. comm.). The exotics Lonicera japonica, Ligustrum sinense, and Microstegium vimineum may invade this community.

Dynamics:  This is a fire-suppressed community, which no longer experiences the historic 1- to 3-year fire-return interval. The total canopy cover is variable; it can range from 90% or more in dense unthinned planted stands to 25% in recently thinned stands. Residual natural stands usually have canopy closures of between 60-80%. This community occurs in central to central western Louisiana, and is topographically isolated from the larger belt of Pinus palustris flatwoods that occurs in southwestern Louisiana and central eastern Texas.

Plantation stands are managed silviculturally. Residual occurrences are fire-suppressed, leading to the increase in shrub and canopy cover. Frequent surface fires historically occurred in these relict stands even during relatively high moisture conditions, and likely had return times of 1 to 3 years. The chief natural fire season in Louisiana is believed to be late March through June (Martin and Smith 1991, 1993). Growing-season fires in the Gulf Coastal Plain have very different ecological effects than dormant-season fires on forb and graminoid flowering and shrub mortality.

The time since the last fire event greatly affects the shrub cover, the herbaceous layer and the regeneration of Pinus palustris. Shrub covers greatly increase with fire suppression, and both the diversity and the cover of the herbaceous layer are dramatically decreased. The natural regeneration of Pinus palustris in this fire-suppressed forest has been curtailed or halted by the lack of exposed soil for germination and safe sites for regeneration.

With the initiation of frequent prescribed burns, it has been observed that this forest community can be restored at least partially to open woodland with an extremely rich herbaceous layer that historically comprised one of the dominant plant communities in this region (R. Stewart pers. comm.). With the continuation of fire suppression, the Pinus palustris canopy will approach an even-aged structure. Eventually the canopy may become mixed as Liquidambar styraciflua, Nyssa sylvatica, Acer rubrum, and Pinus taeda enter this stratum.