CHARLOCK 38s 



The latter is somewhat less pungent than allyl mustard oil 

 obtained from black mustard seeds and is not volatile at 

 ordinary temperatures. 



15. Charlock {Brassica Sinapis N\%. = Sinapis arvensis L.). 

 — A native annual unfortunately often too common in corn 

 fields. 



Seed and Germination. — The seeds are dark brown similar 

 in size to those of turnip, from which they cannot be readily dis- 

 tinguished when the two are mixed. When sown they germinate 

 irregularly and often remain capable of growth for several years 

 when deeply buried in the soil. 



The seeds contain a considerable amount of oil and are sold 

 by many farmers to oil-cake manufacturers, finally appearing 

 as impurities in rape and other ' cakes.' 



The seedling is somewhat like that of a turnip, but can be 

 distinguished from the latter by the first foliage-leaves, which 

 are a darker green colour and of longer and somewhat different 

 shape (B, Fig. 117). It is more pungent in taste than a seedling 

 turnip. 



Stem and Leaves. — The stem is rough from i to 2 feet high 

 and branched. The lower leaves are stalked, ovate, partially 

 lyrate or lobed, the upper ones lanceolate, irregularly serrate, 

 and sessile. 



Inflorescence, Flower and Fruit. — The inflorescence is 

 a raceme. The flowers are larger than those of black mustard, 

 being generally |^ to f of an inch across ; they possess spreading 

 narrow sepals, and pale yellow petals. 



The fruit is a silique from i to 2 inches long, usually with 

 rough deflexed hairs upon it, but occasionally smooth ; the valves 

 of the silique have three faint veins (2, Fig. 123). 



The whole plant resembles that of black mustard, but has 

 larger flowers and differently shaped siliques, which latter are 

 spreading and not pressed to the stem. 



