DESCRIPTIONS OF SOME COMMON WEEDS 



237 



or more, fertile ; achenes smooth, thick, four-angled, trun- 

 cate ; pappus chaffy or two to three-toothed. From New 

 York to Wisconsin, Minnesota and British Columbia and 

 southwest to Missouri, Kansas and Arkansas. 



Eclipta (Eclipta alba, 

 Hassk). A rough, an- 

 nual herb, with oblong- 

 lanceolate or linear-lance- 

 olate, opposite leaves ; 

 heads small, solitary, 

 and many flowered ; 

 scales of involucre 

 leaflike; flowers white; 

 achenes short, three to 

 four-sided, hairy at the 

 summit; four-toothed. 

 Native to Asia and 

 found abundantly in the 

 tropics ; quite common 

 in the United States. 



Coneflower, Nigger- 

 head (Rudbcckia hirta, 

 L.). A rough, bristly, 

 hairy biennial from one 

 to two and one-half feet 



high ; stem simple or Fi - J 49- Greater ragweed (Am- 

 , , , ,. * brosia tnfida). Common in the West 



branched near the base, and es p e cially in grain fields of the 

 bearing a long peduncu- Dakotas. (Clark-Hayden.) 

 late head ; leaves nearly 



entire, the upper sessile, oblong or lanceolate, the lower 

 petioled and spatulate ; heads many-flowered, radiate, the 

 rays about fourteen, neutral ; receptacle columnar or con- 

 ical ; chaff hairy at tip, acutish ; ray-flowers yellow, disk 

 dull brown ; achenes four-angled ; pappus none. Common 

 in dry soils and on prairies and meadows in the eastern 

 states ; introduced largely with clover seed. 



