Middle St. Johns - Florida Department of Environmental Protection

Water Quality Assessment Report: Middle St. Johns 207
Appendix B: Ecological Resources in the
Middle St. Johns Basin
Table B.1: Areas and Descriptions of Natural Communities in the Middle St. Johns Basin
(Community descriptions are adapted from Cox et al., 1994)
Community
Percent of
Acres
Type
Basin Area
Community Description
Uplands
Dry prairie 54,096.80 4.15%
These large native grass and shrub communities are found on flat terrain
intermixed with cypress swamps, bayheads, freshwater marshes, and
hardwood hammocks. This class includes palmetto prairies, which are pine
flatwoods where the overstory has been removed.
Pinelands 170,375.99 13.08%
Pinelands occur on flat, sandy terrain. Dominant overstory trees are longleaf
pine, slash pine, or pond pine. This community includes pine plantations.
Fire is a major source of natural disturbance. Dominance by longleaf pine
occurs on drier, well-drained sites. Pond pine occur on poorly drained sites,
and slash pond occur on intermediate or moderately wet sites.
Sand pine scrub 103,385.55 7.94%
Sand pine scrub, a very dry community, occurs on extremely well-drained,
sterile sands deposited along ridges or former dunes. This community is
dominated by an overstory of sand pine with an understory of myrtle oak,
Chapman's oak, sand live oak, and scrub holly. Ground cover is usually
sparse. Fire is an important land management tool that results in even-aged
stands within regenerated sites.
Sandhill 40,365.38 3.10%
Sandhill communities occur on rolling terrain with deep, well-drained, dry
sandy soils. The overstory is dominated by longleaf pine, with an understory
of turkey oak and bluejack oak. Fire is important for the control of hardwood
species and continued generation of the sandhill community.
Xeric oak scrub 41,532.18 3.19%
This community occurs in areas of deep sands. It comprises clumped
patches of low-growing xeric oak species. Common species are myrtle oak,
scrub plum, sand live oak, Chapman’s oak, and saw palmetto. Fire is an
important factor in maintaining oak scrub.
Mixed pinehardwood
forest
Hardwood
hammock and
forest
23,947.90 1.84%
81,826.79 6.28%
This community contains a relatively equal mix of hardwood and pine species.
Common tree species are beech, mockernut hickory, water oak, loblolly pine,
dogwood, slash pine, longleaf pine, and live oak.
These major upland hardwood-dominated associations are found on fairly rich
sandy soils. They can occur across a range of soil moisture conditions,
including hydric, mesic, and xeric.