266 A GUIDE TO THE WILD FLOWERS 



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Fig, 815. A closely related species, E. maculatum, has thicker 

 leaves, and flat-topped clusters of flower heads, and is found 

 in moist places from Newfoundland to New York and Ken- 

 tucky, and westward. 



816. Marsh Elder. Iva frutescens. (I. oraria.) A perennial, 

 almost shrubby plant, 3-10 ft. high. Leaves thick and fleshy, 

 oval or oval-oblong, mostly opposite, toothed, 4-6 in. long. 

 Flowers tubular, green, in scattered, often inverted heads, 

 mostly among the upper leaves. In salt marshes. Mass. to 

 Florida and Texas. August. Fig. 816. 



817. Galinsoga. Galinsoga parvi flora. A tropical American 

 annual weed, very common nearly throughout North Amer- 

 ica. Stem hairy, 1-2 ft. high, branched. Leaves opposite, al- 

 most stalkless, oval, rounded at the base, pointed at the tip, 

 toothed, 1-3 in. long, rather prominently 3-veined. Flowers 

 tubular, greenish-yellow, the heads long stalked and solitary, 

 or in a sparse cluster. In waste places and in gardens. June- 

 November. Fig. 817. 



818. Ragweed. Ambrosia trifida. A rough, hairy, or some- 

 times smooth weed, 3-10 ft. high, and much branched. Leaves 

 opposite, stalked, deeply 3- or rarely 5-lobed, the lobes 

 toothed, and sometimes there may be also unlobed leaves on 

 the same plant. The lower leaves 7-10 in. wide. Flowers tubu- 

 lar, green, scattered in numerous heads arranged in long 

 spike-like clusters. In waste places, and along river banks, 

 nearly throughout North America. Very common. July-Octo- 

 ber. Fig. 818. A related species, A. elatior, with more finely 



