Flannel Weed 



kept down in wells and tanks by covering them 

 with an opaque cover, as it depends upon light. The 

 ordinary methods of weeding, or rather raking out 

 of the stuff, are only partially successful. Fish often 

 eat considerable quantities of it, and if a sufficient 

 number can be kept in the water, they will do much 

 to keep it in check. If it still persists, then the 

 copper sulphate treatment should be applied. The 

 quantity of water in the pond is estimated.^ For 

 each ten thousand gallons put 2J oz. copper sulphate 

 (blue stone or blue vitriol) into a coarse canvas bag 

 and draw the bag by means of a rope across the pond 

 in every direction until the whole of the copper 

 sulphate is dissolved. The very dilute copper 

 sulphate solution wiU kiU the algae (or " flannel 

 weed ") without harming fish or water-lilies. It 

 may have to be used again during the season, but 

 in still water often keeps the algae from growing for 

 a long time. 



The third case in which plants come into com- 

 petition is on lawns. Here the troubles are usually 

 of two types, the growth of broad-leaved weeds and 

 the growth of moss. The composition of mixed 

 herbage is always determined by two factors — the 

 opportunity various plants have of gaining a footing, 



1 Multiply the average breadth in feet by the length in feet and 

 the product by the average depth in feet. This will give the 

 number of cubio feet contained in the tank or pond. Multiply this 

 result by 6^ (or 6-232 to be more accurate) and the product will be 

 the number of gallons the pond holds. 



22 



