The summer pruning of established wall or espalier-rail trees consists chiefly in the timely displacing, shortening back, or rubbing off of the superfluous shoots, so that the winter pruning, in horizontal training, is little more than adjusting the leading shoots and thinning out the spurs, which should be kept close to the wall and allowed to retain but two or at most three buds. In fan-training the subordinate branches must be regulated, the spurs thinned out, and the young laterals finally established in their places.
Summer and autumn pears should be gathered before they are fully ripe, otherwise they will not in general keep more than a few days. The Jargonelle should be allowed to remain on the tree and be pulled daily as wanted, the fruit from standard trees thus succeeding the produce of the wall trees.
Select list of pears and their period of ripening:— Diseases.—The pear is subject to several diseases caused by fungi. Gymnosporangium sabinae, one of the rusts (Uredineae) passes one stage of its life-history on living pear leaves, forming large raised spots or patches which are at first yellow but soon become red and are visible on both faces ; on the lower face of each patch is a group of cluster-cups or aecidia containing spores which escape when ripe. This stage in the life-history was form erly regarded as a distinct fungus; it is now known, however, that the spores germinate on young juniper leaves, in which they give rise to this other stage in the plant's history known as Gymnosporangium.
Pear trees may also be attacked by a great variety of insect pests. Thus the younger branches are often injured by the pearl oyster scale (Aspidiotus ostreaeformis), which may be removed by washing in winter with lime-sulphur at winter strength. A
number of larvae of Lepidoptera feed on the leaves; the remedy is to capture the matu• insects when possible. Winter moths (Cheirnatobia brumata) and others must be kept in check by putting greasy bands round the trunks from October till De cember or January, to catch the wingless females that crawl up and deposit their eggs in the cracks and crevices in the bark. In the early stages if the entrance of the caterpillars has been detected, a wire should be pushed into the hole. One of the worst pests of pear trees is the pear midge, Diplosis pyrivora, the females of which lay their eggs in the flower-buds before they open. The yellow maggots devour the seeds and thus ruin the crop. When deformed fruits are noticed they should be picked off and burned immediately. Species of aphides may be removed by a nicotine and soap wash. The pear leaf blister mite (Erio phyes pyri) sometimes severely injures the leaves, on which it forms blisters : the best remedy is to cut off and burn the diseased leaves. This remedy can only be applied when the disease is recognized at an early stage. When the disease has obtained a hold, spray during the dormant season with an oil emulsion or a lime-sulphur caustic soda wash. (X.) Cultivation in the United States.—Names and descrip tions of varieties of pears in European publications number about 5,000, while in the horticultural literature of the United States not more than i,000 are to be found. This is an indication that the pear is not as popular in the United States as in France, England, Belgium and Germany, the great pear-growing coun tries of Europe. The reason is that the pear, as compared with other hardy fruits, reaches perfection in comparatively few places in the New World. The climate in most parts of America is un congenial to the pear, a fruit which thrives only in equable cli mates and does not endure well the sudden and extreme variations in climate to which most parts of North and South America are subject. In the United States, commercial pear culture is con fined to favourable localities on the Atlantic seaboard, about the Great Lakes and on the Pacific slope, and even in these favoured regions the product sent to market comes largely from the plan tations of specialists.