720 MASS. BOARD OF AGRICULTURE. 



the English parliament. The slightest knowledge of physiol- 

 ogy should have taught them, that a tree increases its bulk 

 entirely by new layers on the outside of the old wood. Hence 

 when a cavity takes place in the trunk of the tree, it is never 

 filled up. If, however, the tree be young and vigorous, it is 

 often grown over, and the tree outside appears as sound as 

 ever, and in fact may grow and bear fruit for many years after- 

 wards. 



It should, however, be borne in mind that a tree, like every 

 other living being, has its regular period of life. Many forest 

 trees are endowed with a longevity which has no parallel short 

 of antediluvian history. ' There are oaks in this vicinity which 

 were doubtless stately trees when the first white man set his 

 foot on our shores. The regular duration of the apple-tree is 

 much more' limited, and, according to our most accurate in- 

 vestigations, does not, in ' ordinary cases, exceed the term 

 assigned to our own race, say seventy or eighty years, i "When 

 the trees of an orchard, which has been treated with proper 

 care, decay from age, little can be done to renovate them. 

 The better course is, to watch against this event in anticipa- 

 tion, and plant out new orchards in other spots, and thus 

 secure a succession of thrifty bearers. 



Of the various insects which infest the apple-tree, (for almost 

 every tree has several enemies of this description,) the most 

 conspicuous in this neighborhood are the borer, the canker- 

 worm, and the caterpillar. The first of these is described by 

 Dr. Harris, in his Report, p. 89, It attacks the tree at the 

 surface of the ground, or a very little way below, and mines 

 through the trunk, pursuing a slanting course upward. If the 

 tree is of any considerable size, the insect employs several 

 years in reaching the opposite side of the tree. The remedy 

 most commonly suggested is to take him out with a gouge. 

 This, however, is an ineffectual, or rather over-effectual remedy, 

 since it not only destroys the insect, but goes far to ruin the 

 tree. The enemy should be arrested, if possible, at the surface 

 of the bark, or stopped short before reaching it. I was inform- 

 ed by the late S. G. Perkins, that these objects could be 

 effected by examining the trees twice in the year, viz. : in the 

 middle of the months of June and October, destroying the 

 insect if found near the bark, and pouring in a small quantity 



