It is a curious fact that old trees of the Butter pear, which previous to the last appearance of the locusts, had year after year produced worse and worse fruit, until at last it was nothing but knots, are now returning to health and vigor: the pears this season partake of their old character, though still inferior to those formerly produced. We saw these trees dug around just previous to the last appearance of the seventeen-year locusts, and witnessed the fact that the roots were infested with thousands of these insects approaching their perfect state; they were hanging to the rootlets to which they had attached themselves as thick as sucking-pigs, and no doubt took from the tree the nourishment intended for itself. Here is a suggestive fact As the locusts came up, every effort was used to destroy them, as well as those which flew from neighboring gardens, in order to prevent similar future depredations. We might wish that this discovery by a lady of Germantown, Miss Margaretta Morris, an enthusiastic and discriminating naturalist, should be turned to practical account No doubt the larvae are now attacking again the roots of millions of fruit trees, which will depreciate till they are liberated from these merciless suckers.

Rochester, N. Y., August 29,1855.

I have this day received from Mr. John Loughry, of Adams county, Ohio, on the Ohio river, a basket of the most magnificent peaches J have seen in many a year. Oldmixon Cling, and Crawford's Late Melocton, some of which measured 10 inches in circumference. These peaches give positive evidence of two things: first, that southern Ohio is one of the finest peach districts in the Union, and second that Mr. L. is a thorough cultivator. He says in his note to me, that he has fruits which commanded 25 to 100 per cent above the market price in Cincinnati, and that their superiority was due to careful pruning, thinning and culture of the trees.

Another thing worthy the attention of fruit growers and consumers too, is, that these peaches were transported from the southern line of Ohio to Rochester, several hundreds of miles within the past 36 hours, and are now on my table as fresh and handsome as if they had been just picked from a tree in my garden. This all shows what can be done and will be done.

I was in New York city a few days ago, and the thousands of bushels of peaches 1 saw landed in the morning from Jersey, were mere trash. Five dollars per basket was asked for tolerable fair sized and fair looking peaches, $2 for middling, and 91,25 for the very rubbish. Much of the peach culture in New Jersey orchards is of the worst description, and unless a now set of cultivators take the field, Jersey peaches will become a by-word.

I know the season has not been altogether propitious, but the defective culture is the main source of the evil - this has been obvious for many years. The peach trees here that we had almost given up as dead, never looked better, and are preparing to give us an abundant crop next year, provided the mercury dont fall to 26° below 0. 8.

[When will our fruit farmers learn that it is their interest to take more care of their fruit trees ? The same complaint of depreciation in the quality of our market peaches is all but universal in Philadelphia. A few old kinds are occasionally to be purchased of tolerable quality, but as a rule, the peach crop is decidedly inferior to what it ought to be; careless culture, and sometimes a selection of kinds to produce the greatest quantity, regardless of quality, are the sole causes. How much certain "fruit books" have contributed to this, both in peaches and other articles, we shall sometime examine; it has been recommended by some to select one kind of fruit for yourselves, and another "for market," because it looks better or produces a greater amount of saleable product This is wrong; let us always have the best, even at a little advance of price. - Ed].