THE WESTERN YELLOW 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 silvicultural 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 where 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 purpose 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 without 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 environment. 
All mistletoe infection in the vicinity of forest nurseries and planting 
areas should therefore be removed. 
