124 FOREST PROTECTION 



J. General remedies against fungi on live trees. 



I. Extermination or removal of the fungus itself; 



(1) in case of seeds, by sterilization with hot 



water, or copper "steep-mixtures." 



(2) in case of leaf-fungi, by dusting or spray- 



ing with mixtures containing copper or 

 sulphur. 



(3) in case of Agaricacece and Polyporacece, by 



removal of sporophores, by excision; 



(4) in case of dead parts of plants carrying 



sporocarps, or other reproductive stages 

 of fungi, by dead-pruning, or removal 

 of dead litter on ground. 

 II. Extermination of living host or of affected parts of 



(1) Removal of living host. 



(2) Removal of complimentary (heteroecious) 



host. 

 III. Avoidance of conditions favoring infection. 



(1) no wounds, or antiseptic treatment of same; 



(2) avoidance of localities favorable to disease; 



(3) no large, even aged, pure forests; 



(4) no selection systems, no summer cutting; 



(5) rotation of crops; 



(6) no planting of hetercecious hosts together; 



(7) mixed forests; short rotation; suppression of 



boring insects; no artificial pruning of 

 living branches; 



(8) raising strong trees of individual power of 



resistence and independent for help from 

 neighbors; 



(9) improvement cuttings and thinnings. 

 K. General remedies against fungi in nurseries. 



(1) Change of species, notably in nursery beds. 



(2) Sterilized soil in nursery beds. 



(3) Deep trenches between nursery beds. 



(4) Drenching the beds with a weak solution of sulphuric 



acid (one ounce of acid to one gallon of water) 

 prior to seed planting and after the sprouting 

 of the seedlings. Compare Circular No. 4, Bu- 

 reau of Plant Industry. 



(5) Production of fungus proof varieties. 



(6) Spraying of affected leaves or shoots, or beds with 



Bordeaux mixture, consisting of a 3% solution 

 of copper sulphate and lime (Recipe, Tubeuf 

 & Smith, page 69). 



