REPORT OF THE SOCIETY 75 



{Pteris aquilina L.). While cutting is probably the best remedy to employ in the 

 case of these two species there may be considerable areas of land too stony for the 

 use of the scythe. The best chemical to use is common salt, 150 pounds in 60 

 gallons of water per acre. The ferns should be sprayed twice in the season, the 

 first spray being applied before the spores are scattered. While salt has an injur- 

 ious influence on young clover plants it is on the other hand relished by live 

 stock. This difficulty can be surmounted by sowing clover seed after the second 

 spraying. 



Arsenite of soda is equally effective in destroying these ferns but owing to 

 its poisonous nature it is not to be recommended. 



Iron sulphate is stated to be ineffective as a remedy. In Scotland a 5% 

 solution of sulphuric acid applied in July and August proved satisfactory as a 

 remedy for bracken and the cost was only one-third of that of cutting. 



Red Sorrel or Sheep Sorrel {Rumex acetosella L.) . — A spray of 20% solution of 

 iron sulphate applied at the rate of 50 to 75 gallons per acre when the plant is in 

 flower has been found effective. The spray does not injure grasses or grain crops 

 but gives a check to clover and alfalfa. These, how^ever, if the weather is moist 

 soon recover. 



Orchard heating oil kills this plant as well as all other vegetation. When 

 applied in the form of a fine spray a gallon will cover an area of 400 square feet. 

 A second application may be necessary to finish off the weed. 



Lady's Thumb {Polygonum persicaria L.) — This weed may be prevented from 

 ripening seeds by spraying with 20% iron sulphate. 



Redroot Pigiveed {Amaranthus retroflexiis L.). Iron sulphate 20% should be 

 used before it comes into flower. 



Wild Mustard {Brassica arvensis Ktze.). — A solution of iron sulphate (130 

 pounds to every 52 gallons of water per acre) will prove satisfactory and will not 

 injure grain crops. It may be applied with success up to the time of flowering 

 of the mustard. 



Instead of iron sulphate, copper sulphate may be used at the rate of 15 

 pounds in 52 gallons of water per acre. 



A solution of 125 pounds of common salt in 50 gallons of water has been 

 found to be as effective as a 20% solution of iron sulphate and will probably cost 

 considerably less. 



A 10% solution of sulphuric acid applied at the rate of 60 to 134 gallons per 

 acre will destroy wild mustard. 



Wild Radish {Raphanus raphanistrum L.). — A 10% solution of sulphuric 



