220 
THE KIT CHEN-GARDEN. [chap.vii. 
deep strong loam, provided it be well drained, 
and rich rather than poor; and when the 
soil appears exhausted, it may be renovated 
by laying on it what the farmers call a top¬ 
dressing of manure, taking care not to bury 
or even to touch the collar of the tree. 
Apple-trees will, however, flourish in any 
soil except sand or gravel. They are very 
apt to become cankered, and to be attacked 
by the woolly aphis, sometimes called the 
American blight. Canker is generally caused 
by some defect in the drainage or the soil, 
and of course no remedy can be efficacious 
till the cause of the disease is removed; 
when, however, the soil has been renovated 
or drained, the effects of the disease may be 
obviated by heading down the tree, when it 
will produce new and healthy branches; or 
cutting out the cankered part, if they should 
be so low as to make it inconvenient to cut 
off* the trunk of the tree below them. The 
American blight is best cured by brushing 
the parts affected all over with soft soap and 
water; and repeating the operation when¬ 
ever any fresh insects appear. 
The Pear. — The culture of the pear as a 
