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nial grass-like weeds which creep on or below the. surface of 

 the soil. 



The three species of grass usually known by the name 

 " couch " are: 



1) True " Couch " or Twitch " (Agropyron repens, Beauv - 

 Triticum repens, L.). 



2) Black " Twitch " or common Bent grass (Agrostis vulgaris, 



3) Onion " Couch " (Arrhenatherum avenaceum, Beauv. ; var. 

 bulbosum, Lindl.). 



These are among the most troublesome of all weeds of arable 

 land, and when once established a great deal of expense must be 

 incurred before the land is a'gain clean enough for the growth of 

 paying crops. 



- i) As all these pests are spread by means of their 

 seeds which are easily blown about, every effort should be made to 

 prevent flowering, and great care should be taken to procure grass- 

 seeds and seed-corn free from those belonging to these weeds. 



2) Hedgerows must be kept clear of these pests, for from 

 plants growing there seeds are disseminated. Moreover, if the hedge- 

 rows contain couch of any kind, it will grow out into the head- 

 lands, and the first harrowing spreads pieces of rhizomes or the 

 small bulbs " of onion couch further into the field, and year by 

 year the weeds extend. 



3) Where the couch has become established, repeated plough- 

 ing, grubbing, and harrowing during the summer are the only 

 means of dealing with it. The land should be ploughed at first 

 with a shallow furrow, and as much as possible of the weed col- 

 lected by harrowing when the soil is in just the right state of 

 dryness to leave the roots and creeping stems of the weeds easily 

 After gathering together, it should be burnt in heaps and the 

 ashes spread over the land. The passage of a roller over the land 

 greatly assists the harrows and cultivators to shake off the soil 

 from the couch and allow of its collection in unbroken lengths. 



Care should be taken not to grub or harrow in wet weather, 

 especially on the heavier kinds of land, or much mischief will be' 

 done. When wet: the clods are cut or roughly broken by imple- 

 ments into irregular lumps rather than pulverised, and the creeping 

 stems are severed into short lengths too small to be effectively 

 gathered by any implement. A similar state of things also arises when 

 the land is too dry. There is a time in the drying of ploughed 



