420 OBSERVATIONS ON VEGETABLES. 
begin with beech till 1741, and then by seed ; so that my largest is 
now at five feet from the ground, six feet three inches in girth, and 
with its head spreads a circle of twenty yards diameter. This tree 
was also dug round, washed, &c.” Svatton, 24th Fuly, 1790. 
The circumference of trees planted by myself at one foot from 
the ground (1790). 
Oak in 1730 4 ft. 5 in. 
Ash 1730 4 6} 
Great fir 1751 Seo 
Greatest beech 1751 airs, 
Elm 175° 5 3 
Lime 1750 Bae 
The great oak in the Holt, which is deemed by Mr. Marsham to 
be the biggest in this island, at seven feet from the ground, 
measures in circumference thirty-four feet. It has in old times 
lost several of its boughs, and is tending todecay. Mr. Marsham 
computes, that at fourteen feet length this oak contains 1,000 
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 
are 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. According to this suppo- 
sition, a tree may advance in height considerably, though the 
summer shoot should be destroyed every year.— WHITE. 
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. — WHITE. 
