CRUCIFERAE (MUSTARD FAMILY) 183 



the flowers leave behind a string of bead-like silicles of lesser 

 diameter ; as they ripen the tiny balls become netted and pitted, 

 growing smaller yet, until it would take a dozen to measure 

 an inch. Each ball contains one small, yellow seed, which does 

 not "shell" but drops from the plant, pod and all, looking like 

 a speck of dry, brown earth ; the seeds are a common impurity of 

 poorly cleaned grain and are overlooked and mistaken for harmless 

 dirt in seed wheat and oats. (Fig. 126.) 

 Means of control the same as for Field Peppergrass. 



WILD RADISH 



Rdphanus Raphanistrum, L. 



Other English names: Jointed Charlock, 

 White Charlock. 



Introduced. Annual or biennial. Propa- 

 gates by seeds. 



Time of bloom : June to September. 



Seed-time: July to October. 



Range: New Brunswick to Ontario, south- 

 ward to Rhode Island, Pennsylvania and 

 Ohio. Also in British Columbia. 



Habitat: Fields and waste places. 



Root slender, not swollen and fleshy like 

 the garden radish. Stem fifteen to thirty 

 inches tall, erect, branching, sparsely set 

 with fine stiff hairs, or often entirely smooth. 

 Basal and root leaves deeply pinnatifid, with 

 terminal lobe large, and four to six pairs of 

 lateral lobes, decreasing in size toward the 

 petiole, which is short; upper leaves small 

 and oblong, but all are toothed and scalloped. 

 Flowers about a half-inch broad or some- 

 times larger, the four spreading petals pale 

 yellow with purple veins, fading to white as 

 they wither; calyx-lobes drawn close to- 

 gether, instead of spreading like those of 

 Wild Mustard. Pods indehiscent siliques 



... 11 Jc IG. Z /. Wild 



one to two inches long, constricted between Radish (Raphanus Ra- 

 the seeds, faintly grooved lengthwise but phanistrum) . x J. 



