A 8 



igure 2. — Methods of girdling used: (A) In the wide girdling method, a 1- to 2-inch 

 strip of bark and cambium was removed except for a 2- to 4-inch bridge left 

 intact. (B) In the narrow girdling method the bark and cambium was cut through 

 and around the entire bole circumference. Note the installation of a 16-inch- 

 wide aluminum band to prevent squirrels from climbing the tree. 



CONE STIMULATION 



Girdling and release has increased cone production in other pine species (Holmes 

 and Matthews 1951; McCulley 1953; Wenger 1953a, 1953b; Godman 1962). These methods 

 were also used in an attempt to stimulate cone production of ponderosa pine in western 

 Montana. 



Methods 



Wide girdling (fig. 2a) of 15 trees (five each of immature, mature, and overmature 

 trees) and narrow girdling (fig. 2b) of five immature trees was completed at Lick in 

 May 1954. Wide girdles were made by removing a 1- to 2-inch strip of bark and cambium 

 except for a 2- to 4-inch bridge left intact. Narrow girdles were made by a cut through 

 the bark and cambium around the entire bole circumference. Each girdled tree was 

 paired with a nearby untreated but morphologically similar tree. 



5 



