ii4 COMMON WEEDS 



the leaves on long slender stalks ; the seed capsule is 

 the size of a small pea, and contains many triangular 

 blackish or brownish seeds. The ordinary tillage opera- 

 tions are sufficient to keep this little weed within bounds 

 on the farm ; if very plentiful, surface cultivation and 

 one or two well-hoed root crops will reduce it. In 

 gardens the free use of the hoe will suffice. 



POLYGONACE.E 



Persicaria, Redshank (Polygonum Persicaria L.) is a 

 large, freely-seeding annual, often very troublesome, 

 both in gardens and among cultivated field crops. It 

 occurs on most soils, especially those in good condition 

 and fairly moist. Redshank (Fig. 32) is i to 2 feet 

 high, smooth and shiny, branched, and has much 

 swollen nodes, the stem being reddish above. The 

 leaves are lanceolate, almost sessile on the stem, and 

 frequently have a black blotch in the centre. The very 

 small reddish or white flowers are in dense clusters or 

 spikes \ to i^ inch long (Fig. 32, e), and appear between 

 July and October. 



In garden cultivation this weed must be kept under 

 by the use of the hoe, and by hand pulling any tall 

 plants which may escape by growing amongst potatoes 

 and similar crops. The chief thing is to prevent 

 seeding. In field cultivation well-hoed root crops, 

 surface cultivation in spring and early summer, com- 

 bined with hand pulling where necessary, will quickly 

 materially reduce Persicaria. Care should be taken 

 that the seeds are not introduced in dung or in clover 

 and grass seeds. The seeds need little moisture to 

 enable them to germinate. Persicaria is a nutritious 

 plant, and has been given to horses and cattle as a 

 green food. As shown at page 8, it contains a good 



