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Fagaceae
Oak Family
By: George
Rogers
A small
family of about 7 genera and 600 species well represented in temperate and cold
climates in both the Northern and Southern hemispheres. Most are trees, many are
shrubs, including several species native in Florida. This the family of Oaks,
Chestnuts, and Beeches. The great shade tree of the Southern U.S. is Live Oak (Quercus
virginiana). Laurel Oak (Q. laurifolia) is abundant in local
landscaping, and other species crop up infrequently: Water Oak (Q. nigra),
Sand Live Oak (Q. geminata), Turkey Oak (Q. laevis), and rarely
Shumard Oak (Q. shumardii). Additional species are present natively but
negligible in landscaping (Q. minima, Q. chapmannii, Q. myrtifolia).
Key to
Fagaceae Cultivated in South Florida
1. Leaves
deeply 5-9-lobed…2
1. Leaves
entire or scarcely 3-lobed…3
2. Side
lobes flared out broadly (broader toward the tip than at the base); acorn cap
covering < 1/3 of the nut (WU1)…Shumard Oak (Q. shumardii, a more
northern species perhaps shipped infrequently to our area)
2. Side
lobe not flared out; acorn cap covering > 1/3 of the nut (WU1)…Turkey Oak (Q.laevis,
a tree of dry sandy, semi-scrub habitats, not often cultivated)
3. Leave
pubescent (hairy) beneath…4
3. Leaves
glabrous (hairless) or nearly so beneath…5
4. Edges of
the leaves strongly curled under; acorns paired; small trees or shrubs of scrub
areas (but potentially cultivated outside of their natural habitat); arms of
star-shaped hairs rising from the leaf surface (WU1)…Sand Live Oak (Q.
geminata; similar to Live Oak and merged with it into one species by some
authorities, with intergradation and probably environmental effects, Sand Live
Oak occupies one end of a spectrum of variation, being small-statured, having
the leaf blades narrow and with strongly curled margins, the undersides very
hairy, the acorns paired.)
4. Edges of
the leaves slightly curled; becoming massive shade trees; arms of star-shaped
hairs pressed to the leaf surface (WU1)…Live Oak (Q. virginiana)
5. Leaf
blades often obovate (shaped like a light bulb)…Water Oak (Quercus nigra)
5. Leaf
blades mostly elliptic…Laurel Oak (Q. laurifolia) |
