152 COMMON WEEDS 



its occurrence in hedges to the disadvantage of the 

 hedge proper. It appears to flourish best on chalky 

 soils ; the sweet-scented, greenish-white flowers appear 

 in July and August. It can in general be kept in 

 hand by cutting it out regularly when the hedges are 

 trimmed. 



Meadow Rue (Thalictrum flavum L.). Where this 

 plant occurs plentifully it may be a nuisance, as it not 

 only bears seeds, but is extended by a creeping root- 

 stock. It is not commonly a pest, but may become 

 troublesome in wet meadows and damp places near 

 ditches, where it is chiefly found. Meadow Rue grows 

 2 to 4 feet high, has pinnate leaves, and pale yellow 

 flowers crowded in pyramidal umbels, the flowers 

 appearing in July and August. The plant is perennial. 

 It should be exhausted by repeated cutting, and seeding 

 must be prevented ; at the same time the damp land on 

 which it occurs should if possible be drained. 



Buttercups (Ranunculus sp.). Four species of Ranun- 

 culus may be mentioned as occurring freely in pastures 

 and meadows : Upright Crowfoot or Acrid Buttercup 

 (R. acris L.), Bulbous Crowfoot or Buttercup (R. bul- 

 bosus L.), Creeping Crowfoot or Buttercup (R. repens L.), 

 and Lesser Celandine or Pile wort (R. Ficaria L.). All 

 have yellow flowers. The first named is a hairy 

 perennial without runners, with straight fibrous root- 

 stock, cylindrical flower stalks, and well opened flowers 

 | inch in diameter. It flowers from April to September, 

 and occurs on nearly all soils. 



R. bulbosus (Fig. 40) is a hairy erect perennial with 

 a swollen bulb-like stem and no runners, and flowers 

 J to i inch in diameter, with the sepals reflexed so as 

 to touch the stem. Flowering takes place in May to 

 June neither so early nor so late as R. acris. This 

 species appears to favour the lighter and more cal- 



