
Distribution
The blackjack oak grows in poor, thin, dry, rocky or sandy soils where few other woody plants can thrive, usually on low ground, from sea level up to approximately 2,800 feet in altitude. Some say that it does not have the beautiful form of many oaks, but is nonetheless a valuable tree for growing in problem sites. Some say that the tree is "tough but ugly," but also underappreciated. At times the tree has even been actively eradicated to provide more room for trees deemed to be more commercially valuable.It is sometimes an understory tree in pine stands on sandy knolls in the southeastern USA. Along the coastal plain of New Jersey the probability of finding this species is increased in relatively sunny, open areas such as those near coastal salt marshes. It often occurs near scarlet and post oaks as well as pitch pine; understory companions include winged sumac, bracken, sweetfern, and bayberry, and can be found as far north as parts of Ohio and New York.
A variety, ''Quercus marilandica'' Münchhausen var. ''ashei'' Sudworth, grows in the western portions of its range – northern Texas, Oklahoma, and into southern Kansas. In this area, blackjack and post oak form a semi-savanna area composed of forested strips intermixed with prairie grass glades along the eastern edge of the southern Great Plains. This semi-savanna is known as the Cross Timbers. Scrub forms of ''Q. marilandica'' dominate on many chert glades along with ''Q.stellata'' in Arkansas's Ozark plateau.
The Blackjack Oak sometimes hybridizes with the Bear Oak , forming a hybrid known as ''Q. X brittonii''.
Blackjacks in the Cross Timbers can grow from 50 to 60 feet high with a trunk diameter of 16 inches , but seldom reach more than 40 feet . The leaves are from 4 to 10 inches in length and about the same width. Blackjack acorns provide food for both whitetail deer and wild turkey. Blackjacks may, however, cause tannic acid poisoning in cattle.

Habitat
The blackjack oak grows in poor, thin, dry, rocky or sandy soils where few other woody plants can thrive, usually on low ground, from sea level up to approximately 2,800 feet in altitude. Some say that it does not have the beautiful form of many oaks, but is nonetheless a valuable tree for growing in problem sites. Some say that the tree is "tough but ugly," but also underappreciated. At times the tree has even been actively eradicated to provide more room for trees deemed to be more commercially valuable.It is sometimes an understory tree in pine stands on sandy knolls in the southeastern USA. Along the coastal plain of New Jersey the probability of finding this species is increased in relatively sunny, open areas such as those near coastal salt marshes. It often occurs near scarlet and post oaks as well as pitch pine; understory companions include winged sumac, bracken, sweetfern, and bayberry, and can be found as far north as parts of Ohio and New York.
A variety, ''Quercus marilandica'' Münchhausen var. ''ashei'' Sudworth, grows in the western portions of its range – northern Texas, Oklahoma, and into southern Kansas. In this area, blackjack and post oak form a semi-savanna area composed of forested strips intermixed with prairie grass glades along the eastern edge of the southern Great Plains. This semi-savanna is known as the Cross Timbers. Scrub forms of ''Q. marilandica'' dominate on many chert glades along with ''Q.stellata'' in Arkansas's Ozark plateau.
The Blackjack Oak sometimes hybridizes with the Bear Oak , forming a hybrid known as ''Q. X brittonii''.
Blackjacks in the Cross Timbers can grow from 50 to 60 feet high with a trunk diameter of 16 inches , but seldom reach more than 40 feet . The leaves are from 4 to 10 inches in length and about the same width. Blackjack acorns provide food for both whitetail deer and wild turkey. Blackjacks may, however, cause tannic acid poisoning in cattle.

Uses
The wood is very dense and produces a hot flame when burned, which functions as an excellent source of heat for barbecues and wood-burning stoves. However, the wood is not desirable for wood fireplaces because the heat causes popping, thereby increasing the risk of house fires.Traditionally blackjack wood is used as both a fuel and smoke wood for barbecue in Oklahoma.
References:
Some text fragments are auto parsed from Wikipedia.