94 THE ISmiANA WEED BOOK. 



are linear and the flowers in a terminal umbel. The bracts are 

 yellowish when in blossom and the plant is poisonous to stock when 

 eaten in quantity. Wherever found it should be destroyed by re- 

 peated cutting and salting as it crowds out grass and all other 

 plants with which it comes in contact. 



The Sumac Family.— ANACARDIACEJE. 



Shrubs or woody vines with acrid, often poisonous, milky sap 

 and alternate, mostly compound leaves. Flowers in axillary or 

 terminal panicles; calyx small, 5-parted; petals 5, greenish or yel- 

 lowish ; stamens 5 ; ovary 1, 1-celled, 1-seeded. Fruit generally a 

 small drupe. 



A small family with little or no economic value. Only six spe- 

 cies are listed from the State, all sumacs belonging to the genus 

 Rhus. Two of them produce a nonvolatile oil which is very irri- 

 tating to the skin, producing blisters and ulcers. The other five 

 are harmless to the touch. The foliage of one, the smooth sumac 

 (Rhus glabra L.) is used to same extent in tanning leather. An- 

 other, the fragrant or sweet-scented sumac, grows only on rocky 

 banks or cliff's and its foliage gives off a very pleasing odor. No 

 other plants rival these harmless sumacs in the rich splendor of 

 their leaves and fruits in the Indian" summer of late autumn. Then 



"The maples blaze; the tangling sumac shrubs 

 Of glowing spikes build crimson ladders up 

 The wall." 



They are then easily known by the red clusters of fruit, that of the 

 poisonous species being grayish-white and the foliage much more 

 dull. 



57. Rhus kadicans L. Poison Ivy. Poison Oak. Poison Vine. (P. N. 2.) 

 Stem woody, either climbing by numerous air rootlets, or bushy and 

 erect ; leaves 3-parted ; leaflets ovate, pointed, entire or toothed. Flowers 

 green in loose axillary panicles. Fruit grayish-white, smooth, globular, 

 1/6 of an inch in diameter. (Fig. 61.) 



Common along fence-rows, borders of fields and thickets. May- 

 July. Two well known varieties of poison ivy occur in the State. 

 One is a bushy shrub 2-6 feet, high and occurs most commonly 

 about old fences and rocky ledges; the other is a vine 30-150 feet 

 in length, climbing often to the tpps of the tallest trees and found 

 mostly in dry, open woods. The foliage of both is poisonous to 

 most persons, though some can handle it with impunity. Birds 

 feed readily upon the fruit and scatter the seeds far and wide. 

 The poisonous oil is found in all parts of the plant, even in the 



