QUERCUS LAURIFOLIA

شرح

Wunderlin, R. P., B. F. Hansen, A. R. Franck, and F. B. Essig. 2024. Atlas of Florida Plants (http://florida.plantatlas.usf.edu/). [S. M. Landry and K. N. Campbell (application development), USF Water Institute.] Institute for Systematic Botany, University of South Florida, Tampa.

This is a s.lat. species concept. Hunt (1991:74) characterized Q. hemisphaerica as leaves essentially evergreen, blades 3.5-5.5 x 0.7-1.6 cm, basal angle 94-244, apical angle 49-153, coriaceous, lustrous, often dentate, slightly revolute, opaque, essentially glabrous, venation more prominent adaxially, petiole 0.7-1.8 mm, twigs grayish vs. Q. laurifolia s.str. as leaves tardily deciduous, blades 6.5-8.8 x 1.8-2.6 cm, basal angle 20-130, apical angle 144-213, moderately coriaceous, moderately lustrous, never dentate, not revolute, translucent, venation more prominent abaxially, twigs reddish tinted. Hunt (1991:200) also wrote it was the "most difficult pair of taxa to assess"; "It is possible that widespread introgression occurs" and that leaves of Q. hemisphaerica from wet lowlands and of Q. laurifolia from dry uplands often resemble each other which is "particularly evident in Florida" where the two are "abundant yet highly variable" (1991:364); the two "cannot be distinguished chemically" (1991:119); and it "may not always be possible to identify individuals of these species from a single branch" and "it is often unreasonable to expect identification from a single leaf of these species" (1991:204). Monk (1965) summarized the occurrence of Q. laurifolia s.lat. in 60 communities of north peninsular Florida, reporting it as present in 85% of dry, 51% of dry-mesic, 35% of mesic, 49% of wet-mesic, and 31% of wet sites. Duncan & Duncan (1988) observed that Q. hemisphaerica flowered two weeks later in the same general area, also supported by Hunt (1991:164-165). In west-central Florida, flowering specimens of this group have been documented from Jan 28 (Perkins s.n., acc. no. 1966) through Mar 25 (Cole LR0114). The distribution of the two entities in the southeast USA is nearly identical, but Q. hemisphaerica is considered more common in xeric conditions and Q. laurifolia in more hydric conditions. Hipp et al. (2017) found samples of Q. hemisphaerica from North Carolina were more closely related to other species than to Q. laurifolia from Florida.

Synonyms :

Dryopsila laurina

Dryopsila maritima

Dryopsila verrucosa var obliqua

Quercus aquatica var hybrida

Quercus aquatica var laurifolia

References

Wunderlin, R. P., B. F. Hansen, A. R. Franck, and F. B. Essig. 2024. Atlas of Florida Plants (http://florida.plantatlas.usf.edu/). [S. M. Landry and K. N. Campbell (application development), USF Water Institute.] Institute for Systematic Botany, University of South Florida, Tampa.