SIZE AND GROWTH OF TREES. 297 



might then have seen very large trees of my own raising. But 

 I did not begin with beech till 1741, and then by seed; so that 

 my largest is now at five feet from the ground, 6 feet 3 inches 

 in girth, and with its head spreads a circle of 20 yards diameter. 

 This tree was also dug round, washed, &c." Stratton, July 24th, 

 1790. 



The circumference of trees planted by myself at 1 foot from 

 the ground, 1790. 



feet. inches. 



Oak in ...... 1730 4 5 



Ash 1730 4 6 



Great fir 1751 5 



Greatest Beech .... 1751 4 



Elm 1750 5 3 



Lime 1756 5 5 



The great oak in the Holt, which is deemed by Mr. Marsham 

 to be the biggest in this island, at 7 feet from the ground, mea- 

 sures in circumference 34 feet. It has in old times lost several 

 of its boughs, and is tending to decay. Mr. Marsham computes, 

 that at 14 feet length this oak contains 1000 feet of timber. 



It has been the received opinion that trees grow in height 

 only by their annual upper shoot. But my neighbour over the 

 way, whose occupation confines him to one spot, assures me that 

 trees ara expanded and raised in the lower parts also. The 

 reason that he gives is this : the point of one of my firs began 

 for the first time to peep over an opposite roof at the beginning 

 of summer ; but before the growing season was over, the whole 

 shoot of the year, and three or four joints of the body beside, 

 became visible to him as he sits on his form in his shop. Ac- 

 cording to this supposition, a tree may advance in height con- 

 siderably, though the summer shoot should be destroyed every 

 year. 



FLOWING OF SAP. 



IF the bough of a vine is cut late in the spring, just before the 

 shoots push out, it will bleed considerably ; but after the leaf is 

 out, any part may be taken off without the least inconvenience. 

 So oaks may be barked while the leaf is budding; but as soon 

 as they are expanded, the bark will no longer part from the 

 wood, because the sap that lubricates the bark and makes it 

 part, is evaporated off through the leaves. 



