192 
COLLECTIONS AND RECOLLECTIONS. 
been stated before, that when part of the roots of a tree are destroyed, 
some of its branches die; and when that part of its branches are de¬ 
stroyed, some of its roots die. Can it be wondered at then, that the 
stem, which is the channel of communication between the roots and 
branches, should be injured by having a portion of its substance ren¬ 
dered useless ? So long as the fibres and tubes which compose the 
stem are kept in use, and have a stream or current of sap flowing in 
them, there is no chance of decay; it is impossible that decay can 
take place under such circumstances. How desirable then is it, that 
the circulation of the juices through the stem should not be stopped 
or checked. When the limbs of a tree are cut off, some of the sap 
vessels of the stem are rendered useless, and being of no use, they 
contract, and often decay. Their contraction occasions what car¬ 
penters call shakes; and in a tree that has lost many boughs, it may 
be seen that a certain portion of the middle of its stems has con¬ 
tracted and separated from a ring of live wood, which is at the out¬ 
side of the stem, forming a hollow cylinder, enclosing the contracted 
dead wood in the centre. 
This is a very common blemish in pruned timber; but it cannot 
be discovered till the stem is cut through. This is one of the least 
injurious effects that pruning can have on the quality of timber : the 
worst, and by far the most common is, decay, which is almost cer¬ 
tain to take place at the part where a bough has been cut off, and 
which seldom fails sooner or later, to extend itself through the whole 
stem. 
Pruning cannot improve the quality of timber by reducing knot¬ 
tiness. A live knot in timber every carpenter knows to be less hurt¬ 
ful than a dead one. It is impossible to reduce the number of knots 
by pruning, but almost certain that the number must be increased. 
Those who imagine that timber may, by pruning, be rendered less 
knotty, must know but little of that admirable property in trees, to 
adopt the best shape for their situation : they never could have com¬ 
pared the shape of a detached and unmutilated tree in an open situ¬ 
ation, with that of one growing in a grove, and closely surrounded 
by other trees. Let them well consider what is the cause of the 
difference in the forms of the two trees; and when they have disco¬ 
vered and well understand this, I will answer for them, they will not 
attempt to procure the long knotless timber of the grove, from the 
detached tree.— Ballad's Treatise on the Nature of Trees. 
THOMAS HARDCAST1.E, PRINTER, CHURCH-STREET, SHEFFIELD. 
