GTT) JOURNAL OF FORESTRY 



species, whether merchantable or unmerchantable, found infected with 

 wood- rotting fungi, rust, or mistletoe. Diseased trees menacing young 

 growth and sound mature growth should be designated to be cut. 



For the B^, Bo, and Bg stands: If, under the clear-cutting system, 

 there are any trees left standing other than seed trees, designate to be 

 cut all trees of whatever species, whether merchantable or unmerchant- 

 able, infected with rust or mistletoe, in order to protect the reproduction. 



In marking seed trees to be reserved on the area after cutting, only 

 those free from root, butt or trunk rots, and from rust and mistletoe 

 infections should be selected. This is to prevent premature loss of seed 

 trees by windfall or wind-breakage and to prevent the spread of rust and 

 mistletoe infection. Thrifty and healthy seed trees should be selected 

 in preference to all others, wherever possible. 



Mature or veteran trees having defects other than rot, rust, or mistle- 

 toe, unless such defect greatly weakens the resistance to wind-breakage 

 and windthrow, are recommended to be left as seed trees. 



Mature or veteran trees showing indications of rot, but without visible 

 sporophores, should be the last choice for seed trees, in case no sound 

 trees can be found to serve the purpose. \'eteran trees of very old age 

 will rarely live through the second rotation, and most of them will be 

 past the sporophore production period by the time the reproduction has 

 developed the infection age. 



The Larch-Fir Type 



Marking rules for the larch-Douglas fir type have been issued by Dis- 

 trict I of the Forest Service for guidance in drawing up specific rules 

 for individual sales. ^" These rules give the classification of the type 

 under two main heads: I. All-aged stands; II. Even-aged stands. The 

 subdivisions under each of the above heads are as follows : 



1. Immature, with some merchantable timber and consider- 

 able material of tie size — that is. 13 to 17 inches d. b. h. 



2. Mature. 



(a) With more than 50 trees per acre below merchantable 



size. 

 {b) With less than 50 trees per acre below merchantable 



size. 



The marking for I (all-aged stands), II, i, and II, 2 (a) stands pro- 

 vides for a selection cutting, which will leave more than 50 thrifty 

 sound trees 6 inches and over d. b. h. per acre. The marking for II, 2, 

 (&) stands provides for clear cutting with seed trees. In respect to the 



