Pinus elliottii var. densa

Little et Dorman 1952

Common names

South Florida slash pine (Kral 1993).

Taxonomic notes

Syn: Pinus elliottii subsp. densa (Little & Dorman) Murray 1982; P. densa (Little & Dorman) Silba var. austro-keyensis Silba 1990; P. heterophylla (Elliott) Sudworth non Koch 1849, pro parte (e.g. Sudworth 1893, Sargent 1897) (Farjon and Styles 1997); Pinus densa (Little & Dorman) de Laubenfels & Silba. The name Pinus caribaea Morelet has been applied in error to P. elliottii var. densa (Kral 1993, Farjon and Styles 1997).

Description

"Seedlings with vertical growth interrupted by grass stage, stem then more thickened, fascicles much more numerous and crowded around bud, and other buds more approximate on stem. Leaves mostly in 2s, sometimes in 3s on same shoot, resin canals per leaf 3-9, hypodermis (2-)3-4(-5) cell-layers thick. Seed-cone base mostly rounded when open" (Kral 1993).

See the "Remarks" section HERE for details on "grass stage" growth.

This variety is best distinguished by its wood, which is heavier and harder than that of typical slash pine, and by its having a grass stage comparable to that of P. palustris (Kral 1993).

Distribution and Ecology

USA: Florida. Found in flatwoods, mostly over limestone, at 0-10 m elevation (Kral 1993).

Zone 10 (cold hardiness limit between -1°C and +4.4°C) (Bannister and Neuner 2001).

Remarkable Specimens

The largest known tree has dbh 105 cm, height 20 m, crown spread 23 m, located at the University of South Florida, Sarasota, Florida (American Forests 1996).

Ethnobotany

Unlike the type variety, this variety has not been used for naval stores (Kral 1993). However, it is planted for timber production. For example, it is planted for commercial uses by the U.S. Air Force land managers at Avon Park Bombing Range as well as by Lykes Brothers ranch in south central Florida, and seedlings are offered for sale by the Florida Division of Forestry (Jay Frost email 2009.07.04).

The species has some use in dendrochronology. Exploratory work has been done, demonstrating that the species produces annual rings, chronology development is feasible, and that the trees are mainly responsive to variation in summer rainfall (Harley et al. 2011).

Observations

Remarks

Citations

American Forests 1996. The 1996-1997 National Register of Big Trees. Washington, DC: American Forests.

Harley, Grant L., Henri D. Grissino-Mayer, and Sally P. Horn. 2011. The dendrochronology of Pinus elliottii in the lower Florida Keys: chronology development and climate response. Tree-Ring Research 67(1):39-50.

Little, Elbert L., Jr., and Keith W. Dorman. 1952. Slash pine (Pinus elliottii), its nomenclature and varieties. Journal of Forestry 50: 918-923.

See also