WEEDS OF AGRICULTURE. 345 



9. SHEEP'S SORREL, or Dock {rumex acetosella). 



10. KNOT-GRASS, Snake-weed, Red-weed (polj/gonum 

 nviculare). This has already been noticed under the 

 head of '^ Fallow Weeds." 



11. YELLOW RATTLE, or Cock's-comb, Cock-grass, 



Penny-weed, Heny Penny, &-C. {rhinanthus crista 

 galli). 



12. COMMON CARLINE THISTLE {carliua vulgaris). 



The above are more frequently found to infest dry, sandy 

 pastures and calcareous soils, than loamy or damp grass 

 lands. Where they prevail to a great extent, there is no 

 remedy like breaking up the land, and taking a course of 

 crops, for palliative remedies are of little avail. The thistles, 

 sheep's-sorrel, and knot-grass, are the most formidable. 

 Hand-weeding, when the weeds are confined to local spots, 

 and are only just beginning to spread generally over the 

 soil, will be found effectual ; but when once the pasture 

 becomes generally infected with the seeds and roots of these 

 plants, no time should be lost in using the plough, harrow, 

 and horse-hoe, and a judicious course of cleansing crops 

 before returning the land again to permanent pasture. 



Pasture weeds which generally prevail in loamy soils, and 

 such also as are prevalent in clayey and damp soils are prin- 

 cipally as follow. 



1. YELLOW GOAT'S-BEARD (trugapogou pratensis). 



2. MARSH-THISTLE, or Red Thistle {carduus palustris). 



This is almost confined to wet, damp pastures. 



3. MELANCHOLY THISTLE (carduus heteropht/l/us). 



4. MEADOW-THISTLE, or Small Purple Thistle {carduus 



pratensis). , 



