DESCRIPTIONS OF SOME COMMON WEEDS 



173 



except the upper, broadly ovate to lanceolate or cordate, 

 cuneate at the base; flowers in loose inflorescence; slen- 

 der peduncles, smooth or slightly pubescent; fruit oblong- 

 obovate, rather acutely angled. Common in Illinois, to 

 Minnesota, to Texas. 



The western O. hirsutus is glandular hirsute; leaves 

 lanceolate or linear-lanceolate. Western Iowa to Saskat- 

 chewan, Colorado to Texas. The O. linearis is tall and 

 smooth; peduncles hir- 

 sute, with linear 

 leaves. Occurs from 

 Iowa to Utah and 

 Mexico. 



Hogweed (Boerhaa- 

 via ere eta, L.). An 

 annual herb with as- 

 cending stem, branched 

 from base ; swollen 

 joints; leaves ovate or 

 roundish, acute or 

 mucronate, often more 

 or less obcordate, whit- 

 ened and minutely 

 dotted underneath ; 

 flowers perfect without involucre ; clusters three to five- 

 flowered in ample panicles; calyx tube cylindrical, five- 

 ribbed, limb colored, funnel shaped, five-lobed. Common 

 in southern states from South Carolina to Texas. 



Pink Family (Caryophyllaceae). Herbs with opposite, 

 entire leaves, frequently swollen at the nodes ; flowers 

 perfect or rarely dioecious ; sepals four or five, persistent, 

 separate or united with the calyx tube ; petals of equal 

 number, styles two to five, or rarely united into one; 

 ovary usually one-celled, occasionally three to five-celled, 

 ovules attached to a central column; seeds several or 

 many ; small coiled or curved embryo with a mealy albu- 



Fig. 107. Wild four o'clock or um- 

 brella plant (Oxybaphus nyctagineus). 



