_Figure 22._--Fruit of poison sumac, one-third natural size. These fruits somewhat resemble those of poison-ivy. They are always on drooping slender stems attached at the side of the small branches and are never terminal as in the species of sumac that are not poisonous. The plants range in height from 5 or 6 feet to small trees that may attain a height of 25 feet. The poison sumac shrub shown in figure 19 is growing on the edge of a swamp and is quite typical of the general appearance of the larger shrubs, which approach a treelike form. As a rule the shrubs do not have a symmetrical upright treelike appearance. They are more or less inclined to lean and have branched stems with about the same diameter from the ground level to the middle height of the shrub. Occasional isolated plants are found outside of swampy regions. Apparently these plants are started from seed distributed by birds. The plants in dry soil usually do not become more than a few feet tall. They are likely to cause poisoning to unsuspecting individuals, as single isolated plants are not readily recognized, especially out of their usual region. The leaves of the poison sumac are divided into 7 to 13 leaflets, arranged in pairs with a single leaflet at the end of the midrib (fig. 21). _Figure 23._--_A_, Smooth sumac and dwarf sumac growing in a mixed stand. These plants are not poisonous. _B_, Terminal fruiting spike of smooth sumac, about one-seventh natural size. This form of terminal fruiting spike is typical of all the species of sumac that are not poisonous. The leaflets are an elongated oval shape without teeth or serrations on the margins. They are 3 to 4 inches long and 1 to 2 inches wide, with a smooth velvetlike texture and bright orange color when they first appear in spring. Later they become dark green and glossy on the upper surface and pale green on the lower and have scarlet midribs. Early in fall they turn to a brilliant red-orange or russet shade. The small yellowish-green flowers are borne in clusters in slender stems arising from the axis of leaves along the smaller branches. The slender clusters of flowers have much the general appearance of the poison-ivy flower, but hang in much longer clusters. The flowers mature into ivory-white or green-colored fruits resembling those of poison-oak or poison-ivy, except that they are usually less compact and hang in loose clusters that may be 10 to 12 inches in length (fig. 22). CONFUSION OF POISONOUS AND HARMLESS SUMACS