126 



PEINCIPLES AND PRACTICE OF PRUNING 



be co\'crcd with the annual rings of the trunk. Gen- 

 erally such limbs are only one year younger than the 

 trunk at the point where they are produced, but some- 

 times a latent Ijud may develop several years later than 

 the limb produced in normal time. In such cases the 

 initial point of the limb will not be from the central por- 

 tion of the trunk, but from one of tlie annual rings more 

 or less distant from the center of the tree trunk. When- 

 e\'er logs are cut into boards the positions of the limbs 

 on the trunks are shown by the knots (Figs. 80, 81, 82), 

 The history of the limbs is in- 

 dicated by the condition of the 

 knots. \Adien tlie knots form a close 

 union with the trunk the limb dur- 

 ing the life of the tree was healthy 

 — at least at the point where cut 

 (Fig. 82). When the knot is sur- 

 rounded 1)y a black ring, and es- 

 pecially where it is loose and can 

 be knocked out, it shows that the 

 limb was dead at the point where 

 tlie board was cut from the trunk. 

 Farther from the center of the trunk 

 there may be only a hole where the 

 limb has rotted back into the trunk 

 (Fig. 82). 



116. Natural and artificial wounds 

 contrasted. — From what has been 



FIG. S5— FLICKER'S NEST 

 A cut was wTonfily made 

 at thu elhow. Decay spread 

 down the heart wood. An- 

 other stub just below the 

 center also decayed and a 

 flicker dui^ out a nest. This . , . . 



is a common thing in badly said ui the prcvious paragraphs it 



pruned orchards. , . - ,, i 'i 1 , t , 



ma^' be nghtlv concluded that 

 man may take advantage of and imjirove upon na- 

 ture's methods, especially in the making of wounds, 

 for if he will make wounds in such a way as to favor 

 liealing rather than decay, he will increase the longevity 

 and the usefulness of the tree he so prunes. When 



