134 COMMON WEEDS 



fibrous roots at the joints or " nodes," from which 

 flowering stems and leaves are sent up. Where Couch is 

 left undisturbed, or not systematically attacked, it may 

 form a thick mat or "couch" of these underground 

 stems, which are white in colour, and of the thickness of 

 coarse string. Such a mat of so-called " roots" may 

 effectively compete with the sown crop, and even pre- 

 vent more than a small yield being obtained. The 

 flowering spikes are constructed like those of a wheat 

 ear, but the spikelets are not so closely grouped. Unlike 

 those of ryegrass, the spikelets are placed flat on the 

 stem, and not sideways (Fig. 39). 



Couch may be combated in two or three ways. The 

 laying down of the land to pasture is the most radical 

 and effective cure for Couch ; M< Alpine and Wright say 

 that in three years it will have totally disappeared after 

 this treatment. 1 



The general custom on the farm consists in frequent 

 shallow ploughing, followed by the use of cultivators, 

 heavy harrows, and chain harrows, in hot weather and 

 in autumn, in order to bring the plants bodily to the 

 surface, where they may be gathered together and 

 burnt. As even very small pieces may take root and 

 form new centres of infestation, great care should be 

 taken to collect as much as possible, and carry none on 

 implements to neighbouring fields. When the land is 

 dry a heavy roller may be employed to crush the soil 

 from the rhizomes. On heavy land this process of 

 ploughing and cultivating should be arrested in wet or 

 very dry weather, or more harm than good may be done, 

 owing to the repeated breaking of the creeping stems. 



Where Couch or Twitch is very plentiful thorough 

 cleaning may usefully be followed by taking two root 

 crops in succession, when the regular hoeing which 



1 Trans. H. and Agric. Soc., 1894. 



