6iO WEEDS : SPECIAL 



SOROPHULARIACRaE— Yellow Rattle {Rhinanthus Crista- 

 Gain L.). — An erect annual, with stems from 6 to i8 inches 

 high, bearing oblong-lanceolate serrate leaves opposite to each 

 other. The flowers are irregular, with two-lipped yellow corollas 

 and flattened bladder-like cal)rx. The seeds, which ripen early, 

 are thin and flai with a membranous wing round them, and 

 readily blown about by the wind. When ripe, they rattle or 

 rustle in their seed case if shaken. The plant is frequent in 

 dampish pastures and meadows, and is partially parasitic on the 

 roots of other plants. It is not liked by stock either in dry or 

 fresh state, although close depasturing with sheep seems to 

 reduce it. Top-dressings of salt tend to destroy it. 



LABIAT.S. — Self-heal {Prunella vulgaris L.). — A perennial, 

 growing 6 or 8 inches high, with a square stem and creeping 

 root stock. The leaves are entire and ovate. The flowers 

 are purple or blueish, two-lipped and arranged in dense whorled 

 cylindrical heads or spikes. The ' seeds ' (Fig. 203) occur as 

 impurities in clover, and therefore frequently occur in leys on 

 cultivated ground as well as naturally in damp pastures and 

 meadows. 



POLYGONACE.ffi.— Sheep's Sorrel (Rumex Acetosella L.).— 

 A small perennial dock, usually from 6 to 10 inches high, with 

 a branched creeping root stock. The lower leaves are hastate : 

 the male and female flowers are upon separate plants. The fruit 

 is a small triangular nut (2, Fig. 199) and occurs very often as 

 an impurity in clover and grass seeds. 



The whole plant is reddish in autumn, and has an acid taste 

 at all times, due to the presence of acid oxalates. 



It is abundant in dry pastures, and although not in itself a 

 serious pest it is indicative of poor land. 



Liberal dressings of manures and composts reduce it, and 

 applications of lime or manures such as basic slag containing 

 lime, are specially useful where it is prevalent. 



URTICACEJE— Larger Stinging Nettle {Uriica dioica L).— 



