BREWER OAK (_Quercus breweri_) grows on the west slope of the Sierra Nevada mountains in California, from Kaweah river northward to Trinity mountains. It is often little more than a shrub, and its usefulness to man lies less in the quantity of wood it produces than in the protection the dense thickets, with their network of roots, afford steep hillsides. Gullying in time of heavy rain cannot take place where this oak’s matted masses of roots bind the soil. Sprouts rise freely from the roots, and thickets are reproduced in that way rather than from acorns, although in certain years crops of acorns are bountiful. The trunks are too small to make any kind of lumber, but are capable of supplying considerable quantities of fuel.
Post oak is the most common name for this tree but various sections of its range have given it their own names which probably have local significance. The following names are in use in the localities denoted: post oak in the eastern and Gulf states, Connecticut to Texas, and in Arkansas and West Virginia; box white oak in Rhode Island; iron oak in Delaware, Mississippi and Nebraska; chêne étoile in Quebec; overcup oak in Florida; white oak in Kentucky and Indiana; box oak and brash oak in Maryland.
Toward the northern portion of the range of this tree it is small, and in early times it was little used except for fence posts. Its durability fitted it for that use, and it is said the common name was due to that circumstance. The name iron oak was used by shipbuilders who sometimes bought small knees made of this wood. Baltimore oak was an early name which is not now in use. It was generally applied to white oak, but it included some post oak shipped from the Chesapeake bay region.
Post oak is botanically and commercially a white oak and is seldom distinguished from the true white oak, _Quercus alba_, in commerce. It is seen at its best in the uplands of the Mississippi basin and in the Gulf states west of the Mississippi, where it attains a considerable size. In the northeastern states and in Florida it is small, becoming shrubby in some localities, and more or less of local growth. Limestone uplands or dry, sandy or gravelly soils seem to offer the best conditions for its existence, where it grows in company with black jack, red and white oak, sassafras, dogwood, gums, and red cedar.