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Quercus stellata Wangenh.
The range of post oak extends from southeastern Massachusetts, Rhode Island, southern Connecticut and extreme southeastern New York (including Long Island); west to southeastern Pennsylvania and West Virginia, central Ohio, southern Indiana, central Illinois, southeastern Iowa and Missouri; south to eastern Kansas, western Oklahoma, northwestern and central Texas; and east to central Florida (10).
It is a large and abundant tree in the southern Coastal Plain, the Piedmont, and the lower slopes of the Appalachians. It is common in the southwest and grows in pure stands in the prairie transition region of central Oklahoma and Texas known as the "Cross Timbers" (2).
Sand post oak (Quercus stellata var. margaretta (Ashe) Sarg.) ranges from southeastern Virginia, west to Missouri and eastern Oklahoma, south to central Texas, and east to central Florida. Delta post oak (Q. stellata var. paludosa Sarg.) is found in bottom lands of the Mississippi River in western Mississippi, southeast Arkansas, and Louisiana, and west to east Texas (10).
-The native range of post oak.
Quercus stellata is often identified by its commonly cross-shaped leaf form, particularly in the eastern part of its range. All individuals and populations do not express this characteristic, however. Moreover, Q . stellata has broad overlap with Q . margaretta and even with some forms of the blackjack oak, Q . marilandica , one of its most common associates. The thick yellowish twigs with indument of stellate hairs and the dense harsh stellate hairs on the abaxial leaf surface are better diagnostic characteristics when variation includes leaf forms that are not obviously cruciform.
Native Americans used Quercus stellata medicinally for indigestion, chronic dysentery, mouth sores, chapped skin, hoarseness, and milky urine, as an antiseptic, and as a wash for fever and chills (D. E. Moerman 1986).
Putative hybrids are known with Quercus marilandica , Q . alba , and various other white oaks. Quercus stellata is also one of the few oaks that appears to produce hybrids with species in the live oak group, although obvious intermediates are rarely encountered. Nothospecies names based on putative hybrids involving Q . stellata include: Q . × stelloides E. J. Palmer (= Q . prinoides × Q . stellata ), Q . × mahloni E. J. Palmer (as Q . sinuata var. breviloba × Q . stellata ), Q . × pseudomargaretta Trelease (= Q . margaretta × Q . stellata ), Q . × sterretti Trelease (= Q . lyrata × Q . stellata ), Q . × macnabiana Sudworth (= Q . sinuata × Q . stellata ), Q . × guadalupensis Sargent (= Q . sinuata × Q . stellata ), Q . × fernowi Trelease (= Q . alba × Q . stellata ), and Q . × bernardensis W. Wolf (= Q . montana × Q . stellata ).
|Rights holder/Author||eFloras.org Copyright © Missouri Botanical Garden|
Trees , deciduous, to 20(-30) m. Bark light gray, scaly. Twigs yellowish or grayish, (2-)3-5 mm diam., densely stellate-pubescent. Buds reddish brown, ovoid, to 4 mm, apex obtuse or acute, sparsely pubescent. Leaves: petiole 3-15(-30) mm. Leaf blade obovate to narrowly obovate, elliptic or obtriangular, 40-150(-200) × 20-100(-120) mm, rather stiff and hard, base rounded-attenuate to cordate, sometimes cuneate, margins shallowly to deeply lobed, lobes rounded or spatulate, usually distal 2 lobes divergent at right angles to midrib in cruciform pattern, secondary veins 3-5 on each side, apex broadly rounded; surfaces abaxially yellowish green, with crowded yellowish glandular hairs and scattered minute, 6-8-rayed, appressed or semi-appressed stellate hairs, not velvety to touch, adaxially dark or yellowish green, dull or glossy, sparsely stellate, often somewhat sandpapery with harsh hairs. Acorns 1-3, subsessile or on peduncle to 6(-40) mm; cup deeply saucer-shaped, proximally rounded or constricted, 7-12(-18) mm deep × (7-)10-15(-25) mm wide, enclosing 1/4-2/3 nut, scales tightly appressed, finely grayish pubescent; nut light brown, ovoid or globose, 10-20 × 8-12(-20) mm, glabrous or finely puberulent. Cotyledons distinct.
|Rights holder/Author||eFloras.org Copyright © Missouri Botanical Garden|
Fagaceae -- Beech family
John J. Stransky
Post oak (Quercus stellata), sometimes called iron oak, is a medium-sized tree abundant throughout the Southeastern and South Central United States where it forms pure stands in the prairie transition area. This slow-growing oak typically occupies rocky or sandy ridges and dry woodlands with a variety of soils and is considered drought resistant. The wood is very durable in contact with soil and used widely for fenceposts, hence, the name. Due to varying leaf shapes and acorn sizes, several varieties of post oak have been recognized-sand post oak (Q. stellata var. margaretta (Ashe) Sarg.), and Delta post oak (Quercus stellata var. paludosa Sarg.) are included here.
More info for the terms: natural, tree
Post oak occurs as a dominant tree in savannas and in forests adjacent
to grasslands. It forms pure stands or mixed stands with blackjack oak
(Quercus marilandica) in the prairie transition area of central Oklahoma
and Texas, where the eastern deciduous forests grade into the drier
western grasslands [43,47].
The following published classifications list post oak as a dominant or
Forest vegetation of the lower Alabama Piedmont 
The natural communities of South Carolina 
Forest vegetation of the Big thicket, southeast Texas 
Eastern Deciduous Forest 
Old-growth forests within the Piedmont of South Carolina 
The natural forests of Maryland: an explanation of the vegetation map of
More info on this topic.
More info for the terms: association, climax, codominant, competition, xeric
Facultative Seral Species
Post oak is intolerant of shade and competition. Because of slow growth
it is often overtopped by other species, including most oaks. It
persists and becomes dominant on poor sites because of its drought
resistance . Delta post oak is moderately intolerant of shade .
Post oak is common in the understory of pine (Pinus spp.)-hardwood
forests. In the absence of fire, post oak may become dominant depending
on site conditions and competition from associated species . In an
upland longleaf pine forest in the west Gulf Coastal Plain, post oak,
along with blackjack oak, bluejack oak, and black hickory (Carya
texana), became codominant and eventually replaced longleaf pine .
Post oak will expand into adjacent prairies in the absence of fire .
The post oak-blackjack oak association may be an edaphic climax on dry
Some of the most xeric sites of the South Carolina Piedmont are occupied
by old-growth communities of post oak, black oak, and blueridge blueberry
(Vaccinium vacillans). Although the community appears to be in steady
state, it may evolve into a hickory-dominated community in the absence
of fire .
More info for the terms: competition, hardwood
Post oak is susceptible to most insects and diseases that attack eastern
oak species. Chestnut blight fungus (Cryphonectria parasitica) attacks
post oak throughout most of its range .
Gypsy moth (Lymantria dispar), which has defoliated and killed
northeastern oak species, showed 17 percent survival in feeding trials
using post oak. This exotic moth has been spreading southward from New
England and, if not contained, could become a problem for post oak
Hardwood competition in pine plantations and hardwood expansion into
grasslands are often controlled with herbicides. Tebuthiuron and
triclopyr are extremely effective on post oak in grasslands of the Cross
Timbers area of Oklahoma .
Quercus stellata is an oak in the white oak group. It is a small tree, typically 10–15 m tall and 30–60 cm trunk diameter, though occasional specimens reach 30 m tall and 140 cm diameter. It is native to the eastern United States, from Connecticut in the northeast, to central Texas in the southwest. It is one of the most common oaks in the southern part of the eastern prairies, such as in the Cross Timbers.
Quercus stellata is often identified by its commonly cross-shaped leaf form, particularly in the eastern part of its range. All individuals and populations do not express this characteristic, however. Moreover, Q . stellata has broad overlap with Q . margaretta and even with some forms of the blackjack oak, Q . marilandica, one of its most common associates. The thick yellowish twigs with indument of stellate hairs and the dense harsh stellate hairs on the abaxial leaf surface are better diagnostic characteristics when variation includes leaf forms that are not obviously cruciform.
|Rights holder/Author||Nathan Wilson, Nathan Wilson|
|Source||No source database.|
More info on this topic.
This species is known to occur in association with the following cover types (as classified by the Society of American Foresters):
More info for the terms: hardwood, swamp
40 Post oak - blackjack oak
43 Bear oak
44 Chestnut oak
45 Pitch pine
46 Eastern redcedar
51 White pine - chestnut oak
52 White oak - black oak - northern red oak
53 White oak
69 Sand pine
70 Longleaf pine
71 Longleaf pine - scrub oak
72 Southern scrub oak
75 Shortleaf pine
76 Shortleaf pine - oak
78 Virginia pine - oak
79 Virginia pine
80 Loblolly pine - shortleaf pine
81 Loblolly pine
82 Loblolly pine - hardwood
83 Longleaf pine - slash pine
84 Slash pine
91 Swamp chestnut oak - cherrybark oak
110 Black oak
More info for the terms: hypogeal, litter, monoecious, root crown
Sexual: Post oak is monoecious. Seed production begins when the tree
is about 25 years old. Good crops occur at 2- to 3-year intervals.
Post oak does not produce as many acorns as white oak, blackjack oak,
black oak (Quercus velutina), or scarlet oak (Q. coccinea) .
Acorns germinate in autumn soon after falling. Germination is hypogeal.
The ideal seedbed is moist soil covered with 1 inch (2.5 cm) or more of
leaf litter. Height and diameter growth are slow; 10 year d.b.h. growth
generally averages less than 2 inches (5 cm). Post oak usually grows
more slowly than any associated trees except blackjack oak .
Average annual height growth of seedlings in Missouri during a 6 year
period was 2.5 inches (6.4 cm) .
Seedlings are resistant to drought but not to flooding . Post oak
seedlings were more drought tolerant than white oak, black oak, or
northern red oak (Q. rubra), primarily because of greater drought
tolerance of leaf and root cells .
Vegetative: Trees up to 10 inches (25 cm) in d.b.h. sprout prolifically
from the root crown after being top-killed. Post oak tends to have
fewer sprouts per clump than black, chestnut, white, or scarlet oaks
. Post oak sprouts grow faster than seedlings . In the Cross
Timbers area of Oklahoma, post oak often occurs in small clusters of two
to six trees. These clusters may represent a single individual because
the species occasionally reproduces vegetatively from roots, especially
under moisture stress .