THE WESTERN YEIZ.OW PINE MISTLETOE. 33 



Lightly infected yellow pines should be left when uninfected trees or 

 lightly infected black jacks are not available for seed and protection. 



Moderately infected trees should always be marked for cutting, 

 except where there are no other trees available to leave as seed trees. 

 Mistletoe can not in all cases be eliminated in one cutting without 

 too great a sacrifice of silvicultujral requirements. Moderately 

 infected trees should not be left for seed on lightly infected areas if 

 healthy trees are available within 100 yards. This, however, applies 

 to large areas rather than to small openings or small areas which have 

 a chance to seed in from surrounding trees and wh§re infection might 

 be removed completely without opening the forest too extensively. 

 Moderately infected trees should be left for soil-protection purposes 

 only on the most adverse sites, where their need for this piu'pose is 

 clearly evident. 



Areas of heavy infection on which the injury from mistletoe is 

 alarming should receive special attention and should be treated from 

 the standpoint of the sanitation of the forest. Areas where the 

 entire stand is too heavily infected to permit carrying out sanitation 

 measures mthout material interference with the silvicultural require- 

 ments of the forest should be marked for clear cutting. In practice 

 such a condition will seldom be encountered. The largest possible 

 number of small trees infected with mistletoe should be utilized. 

 Areas of unmerchantable reproduction infected with mistletoe should 

 be freed of the disease either through cutting the diseased seedlings 

 and saplings or by pruning off infected branches. In certain cases it 

 would be desirable for the owner of the forest to devote special funds 

 for mistletoe-control projects, as is done in the case of serious insect 

 infestations. 



While the areas infected with mistletoe to such an extent that 

 diseased trees must be left or the stand practically clear cut, are not 

 extensive, areas will probably be found on which forest planting to 

 fill in blank growing spaces will be desirable following operations 

 approaching a clear cutting under a mistletoe-control project. It 

 may also be advisable from the standpoint of economy to clear-cut 

 and plant certain limited areas of heavy infection. A definite policy 

 of mistletoe control should be adopted for mistletoe-infected areas 

 to be cut over by timber sales. Necessary funds should be provided 

 to complete the cleaning of the areas after the operator has removed 

 all of the diseased trees which he can be required to take under the 

 agreement. 



Forests in the vicinity of nurseries and planting areas should 

 present unusually healthy conditions. It should be remembered 

 that healthy trees can not be grown in an insanitary envu'onment. 

 All niistletoe infection in the vicinity of forest nurseries and planting 

 areas should therefore be removed. 



