In selecting young pear trees for walls or espaliers, some persons prefer plants one year old from the graft, but trees two or three years trained are equally good.
The mode most commonly adopted of training wall pear-trees is the horizontal.
One of the worst pests of pear trees is the pear midge, known as Diplosis pyrivora or Cecidomyia nigra, the females of which lay their eggs in the flowerbuds before they open.
Although the crop of orchard fruits was no greater in 1899 than in 1889 the Number of apple trees increased during the decade from 1,744,779 to 2,034,398, the number of peach trees from 19,057 to 48,819 and the number of plum trees from 10,151 to 18,137; in the number of pear trees and of cherry trees there was a slight decrease.
The value of the orchard products is large, and is steadily increasing: in the decade1890-1900the number of pear trees increased from 204,579 to 868,184, and between 1889 and 1899 the crop increased from 157,707 to 231,713 bushels.