The Mccook Tribune

Blight of Fruit Trees.

It is quite generally agreed that rapidly growing trees are more apt to be attacked by blight than slower growing ones, said Frederic Cranefield in an address. In general terms, conditions conducive to rapid growth in the apple and pear are conducive to blight. Heavy manuring and cultivation both induce a rapid growth and the new rapidly growing tissues are the first attacked. Old bearing trees growing in sod land rarely suffer from twig blight. There is but little new growth on such trees. A circular letter was sent to many fruit men in Wisconsin last year from the station, requesting answers to numerous questions, among them this one: "Is the blight more destructive to the trees that are cultivated or to those on sod land?" Ninety-eight per cent of those who answered, stated that the trees on cultivated land suffered most. When you ask for reports on the extent of blight as affecting different varieties, most conflicting answers are sure to be received. According to my present limited knowledge, I doubt if any variety of apple at least is more subject to blight than any other. Neither have I been able to learn that any variety is immune. The same is probably true of pears. Any conditions that induce rapid growth, afford conditions favorable to the blight bacteria. Remedies: This end of the subject is of the most interest to fruit growers and unfortunately with our present knowledge of the disease, the one that can be presented with the least satisfaction. However, it is generally agreed that spraying is of no value in checking blight. The organism that causes the disease works wholly within the bark in twig blight at least and is therefore beyond the reach of sprays. If we treat our orchards so as to induce an excessive growth, we lay the trees open to attack by blight while if only a normal growth occurs, they are less likely to be attacked. We can certainly check the disease in any case by cutting out the blighted twigs in summer, if cut back one or two feet beyond the visible point of injury. The most valuable work consists in cutting out every blighted twig late in the fall in order to remove any possible cases of "hold-over" blight.