76 FARM WEEDS OF CANADA 



TALL BUTTERCUP (Ranunculus acris L.) 



Other English names: Tall Crowfoot, Meadow Buttercup. 



Introduced from Europe. Perennial, with fibrous roots. 

 Stem erect, generally hairy. The leaves in 3 divisions, each 

 division stalkless, 3-cleft or parted, with deeply lobed segments. 

 Flowers yellow. The dry seed-like fruits are in heads. 



The seed (Plate 73, fig. 25) is about 1/8 of an inch in diameter, 

 fiat, nearly round in outline but unsymmetrical with a somewhat 

 wing-like margin; both the tip and the scar ends are pointed and 

 very prominent, the former generally hooked. The colour 

 varies from greenish-brown to nearly black; dull from the rough- 

 ened surface. 



Time of flowering: June to August; seed ripe by July. 



Propagation: By seeds. 



Occurrence: Throughout Canada, especially in moist lands. 



Injury: A noxious weed with a poisonous, acrid, blistering 

 juice; common in pastures and meadows. Farm stock will not 

 feed within range of the leaves. When cured in hay it appears 

 to be less objectionable. It does not give trouble in well-drained 

 soils cultivated under a systematic short rotation of crops, 

 but it is difficult to suppress on lands left to permanent pasture 

 or hay. The seeds are commonly found in grass and clover seed. 



Remedy: When possible bring land under cultivation 

 and good drainage. Summer or autumn fallowing, when the 

 land is dry, is efficacious. Postpone seeding to grass until the 

 weed is completely suppressed. Pasture lands that cannot be 

 cultivated should be gone over two or three times each year 

 and the plant closely cut, first when in early bloom and again 

 about July or August. If continued for two or three years, 

 this practice will usually suppress it. 



ALLIED SPECIES: Several allied species are prevalent 

 in many districts as weeds of secondary importance. 



