The post oak is a rougher and coarser tree than the other, and is sometimes called iron oak on account of its very hard, tough wood.
Fig. 81. Leaf of Mossy-Cup Oak
29. The Mossy-Cup Oak. One of the most beautiful oaks we have in America grows in the South and West, and is only rarely found in our parks in the East. It is called the mossy-cup oak because the large acorn which it bears is surrounded by a bushy fringe which almost hides the nut. This acorn is a sight never to be forgotten. The leaf is larger than that of the white oak, and although the two leaves look somewhat alike, the divisions of the mossy-cup leaf are not as regular as those of the white oak, and it is not so thin and delicate.
Its wood is very strong and is valuable for many purposes, such as boats, carriages, farming implements, railroad ties, and cooperage.
30. Black Oak and Black-jack Oak. These two trees are usually found growing in wild places, and the black-jack oak is often called barren oak from the fact that it frequents bleak and barren plains, such as the sandy stretches of New Jersey and Long Island.
Fig. 82. Leaves of Black Oak and Black-jack Oak (Black-jack on right)
The sketch shows the difference in the leaves, that of the black-jack having only three main lobes, or divisions, while the black oak has five. However, the leaves of these two trees vary considerably, and one must always look for the typical leaf, which is the one shown in the sketch. The black-jack is a small, shrubby tree, with branches often twisted and contorted, and its wood is not very valuable except as fuel or for making charcoal.
