Blackberry plants are sometimes laid down in cold climates,—the tops being bent over and held to the ground by earth or sods thrown on their tips (Fig. 155).
The most troublesome disease of the blackberry is orange rust (conspicuous on the under sides of the leaves), which often proves very destructive, particularly to Kittatinny and a few other sorts. There is no remedy, and on the first appearance of the disease the infected plants should be dug up and burned.
Varieties of blackberries.
Many of the better varieties of blackberries are lacking in hardiness, and cannot be grown except in the more favorable localities. Snyder and Taylor are most generally successful, although Wilson and Early Harvest are often grown on a large scale for market, and do well with winter protection. Eldorado is much like Snyder, that seems hardy and productive. Erie, Minnewaski, Kittatinny, and Early King are in many sections large and valuable sorts.
Cherry.—Of cherries there are two common types, the sweet cherries and the sour cherries. The sweet cherries are larger and taller-growing trees. They comprise the varieties known as the hearts, bigarreaus, and dukes. The sour cherries (Fig. 275) include the various kinds of morellos and pie cherries, and these usually ripen after the sweet cherries.
The sour cherries make low, round-headed trees. The fruits are extensively used for canning. Sour cherries thrive well on clay loams. The sour cherry should be planted 18 by 18 ft. apart, in well-prepared, under-drained soil. The trees may be slightly trimmed back each year, keeping the head low and bushy.
The sweet cherries have proved disappointing in many instances from the rotting of the fruit. This may never be entirely avoided, but good cultivation, soil not too rich in nitrogen, attention to spraying, and picking the fruit when dry, will lessen the loss very much. In years of severe rotting the fruit should be picked before it becomes fully ripe, placed in a cool, airy room and allowed to color. It will be nearly as well flavored as if left on the tree; and, as the fungus usually attacks only the ripe fruit, a considerable part of the crop may be saved. Set the trees 25 or 30 ft. apart. Only very well-drained land should be devoted to sweet cherries, preferably one of a somewhat gravelly nature.
Leaf-blight is readily controlled by timely spraying with bordeaux mixture. The curculio or fruit worm may be controlled by jarring, as for plums, or by spraying. The jarring process is seldom employed with cherries for the curculio, inasmuch as the poison spray seems, for some reason, to be particularly effective on these fruits.
Varieties of cherry.