132 A NATURALIST IN THE GREAT LAKES REGION 



Back of the pine association comes in order the black oak 

 association. No single association of the dune complex is more 

 distinctive than this association, so many of the plants are pecul- 

 iar to it. The black and chestnut oaks are the common large 

 trees. There is a wealth of characteristic small trees and shrubs, 

 sassafras, shadbush, pincherry, chokecherry, hop tree, dwarf 

 blackberry, known by its stiff 

 prickers, huckleberry, blueberry, 

 bush honeysuckle. The conspicu- 

 ous herbaceous flowering plants are 

 equally characteristic; the spider- 

 wort, bastard toadflax, anemone, 

 columbine, rock cress, lupine, hoary 

 pea, bush clover, wild geranium, 

 milkweed, flowering spurge, bird's- 

 foot, and arrow-leaved violets, 

 prickly-pear cactus (Fig. 60) , butter- 

 fly weed, green milkweed, wild 

 bergamot, lousewort, blazing star 

 (Fig. 134), the goldenrods, the sun- 

 flowers, and yellow daisy. 



Sassafras (Fig. 112) is readil 

 known by its green twigs with 



FIG. II3 .-Poison ivy, Rku, ^ taste an <* its Bitten 

 Toxicodendron; a, spray showing shaped leaves. Shadbush (Fig. 114) 

 aerial rootlets and leaves; b, fruit also known as SUgar plum, servic 



bush, and June berry, is a sm 

 tree with smooth, light-gray bar 



The leaves of the species in the dunes are thin, and the ed 

 finely saw-toothed. The tree bears clusters of rather large whi 

 blossoms in the spring and later edible fruits that turn red and th 

 purple as they ripen. Pin and chokecherries are known by thei 

 reddish bark that peels off in thin layers like birch bark, though 

 not so readily, and that is marked by conspicuous horizontal 

 lenticels. Both trees have the blossoms in clusters. In th 



both one- fourth natural size 

 (Farmers' Bulletin No. 86). 



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