WEEDS AND WEED SEEDLINGS. 



31 



Charlock and other crucifers. 



Insects or Fungi. Weed " Hosts 



Turnip " fly " or flea beetle 

 Turnip Gall Weevil . 

 Celery Fly 

 Bean Aphis 



Finger- and-toe of turnips, etc. 

 Sclerotium disease 

 White Eust of Cabbages, etc. 



Thistles, 



Goosefoot, Docks. 

 Charlock and other Crucifers. 

 Many weeds. 



Shepherd's Purse and other Cru- 

 cifers. 



Gooseberry-leaf Cluster-cups . Sedges. 



Money losses due to weeds are often very considerable, and have 

 been shown by various experiments to be even as much as 67 per cent, 

 of the crop when weeding has not been practised. At Eeading College. 

 Farm the difference in yield between * ' no weeding ' ' and keeping clean 

 by hand after the mangold crop was singled was as that between 100 and 

 240, the actual yields being 16^ tons and 39 tons respectively. Korsmo 

 found a weedy plot of potatos to yield 4 tons 10 cwt. from an acre, 

 while a clean plot yielded 8 tons 15 cwt. A clean plot of barley 

 yielded 18 cwt. of grain, and a weedy plot only 6' 6 cwt. In a German 

 trial two plots of oats infested with charlock yielded 45 bushels 

 and 24'8 bushels respectively, while plots kept free from charlock 

 yielded 67 and 76'5 bushels respectively. 



Preventive and Eemedial Measures. 

 In an endeavour to combat weeds, irrespective of their class or kind, 

 a number of preventive and remedial measures should always be 

 adopted. 



(1) Thorough cultivation of the soil by spade and fork, and the 

 free use of the hoe, will go far to keep down weeds. 



(2) In all cases and at all times of the year a strenuous endeavour 

 must be made to prevent weeds from seeding — and if weeds are faith- 

 fully attacked in their seedling stages this plan will be successful. 



(3) Perennial weeds need repeated cutting down, and such a step 

 will gradually weaken and exhaust them, for they use up, their reserves 

 of food in a continued endeavour to produce fresh foliage, flowers and 

 seed. Eepeated cutting off will exhaust and destroy weeds like the 

 creeping thistle, coltsfoot, and other plants, but the cutting must be 

 persistent and thorough over perhaps two or three years. 



(4) Pure seed must always be employed, and a guarantee as to 

 purity and germinating capacity should be obtained when seeds are 

 purchased. 



(5) Surface cultivation in spring, to produce a fine tilth and induce 

 weed seeds to germinate, is an excellent plan, for the seedlings can 

 then easily be destroyed by hoeing. The operation should be repeated 

 as often as circumstances will allow. 



(6) Heavy crops tend to keep down weeds, and this fact has led to 

 the growth of such crops as vetches, lucerne, maize, rye, and buck- 

 wheat, all of which by their " crowding " action help to choke out weeds. 



