Descriptive Flora 



213 



(2) Stems smooth, hollow . 



across 



.Viguiera— 230 

 Senecio— -240-1 



b. Flowers white. 



1. Strap-shaped rays none, corollas all 



tubular. 



(1) Leaves linear, flowers over %" 



across 



(2) Leaves not linear, flowers less 



Marshallia — 235 



than across . 



Coleosanthus — 216 



AMBROSIACEAE. Ragweed Family. In Small's Flora. 



Stout, rough stemmed plants with large, 3-nerved leaves as 

 broad as long, inconspicuous heads of greenish-yellow flowers, 

 followed by 2-beaked burs, about 1" long, and covered with stout, 

 hooked, hairy spines. Leaves alternate, simple. Blades rough, 

 3-nerved, broader than long, heavily veined underneath, often 

 3-lobed, coarsely toothed, on long, rough, stout, grooved petioles 

 One of our most pestiferous weeds as the burs catch into clothing 

 and hair and are difficult to remove. Mr. G. Schmeltzer of San 

 Antonio reports this a valuable plant for rattle snake bite. In 

 an emergency, beat leaves to a pulp and apply as a poultice to 

 the wound. Then make a tea of the green fruits or leaves, by 

 brewing 1 cup of mashed material with 3 cups of water. Use 1 

 teaspoonful at a time which will cause severe vomiting and 

 releave the stomach of the poison venom. Do this until the black 

 fluid ceases to come from the stomach. 



Ambrosia aptera DC. Blood-weed. Giant Ragweed. 



Tall, coarse, rough-stemmed weed, often attaining 12 feet, 

 and exuding dark red sap that looks like blood where the stem is 

 broken. Leaves simple, opposite. Blades large, rough, 4 to 12" 

 long, upper strongly 3-lobed, lower 5-lobed, the middle lobe often 

 3-lobed. Flowers inconspicuous. Summer and fall. A common 

 low ground weed. It is the pith of this weed which is used by 

 farmers and ranchmen to stop leaks in water tanks and troughs. 



XantMum echinatum Murr. 



Cocklebur. 



