556 APPENDIX. 



This is owing plainly to two causes. First to the lightness 

 of the soil, which in this climate, under our hot sun (as we have 

 already remarked), lays the foundation of more than half the 

 diseases of fruit-trees because, after a few years, the necessary 

 sustenance is exhausted by the roots of a bearing tree, and 

 every one knows how rarely it is re-supplied in this country. 

 We can from our own observation on the effects of soil, take a 

 map and mark out the sandy district on the whole sea-board, 

 where certain sorts of pears no longer bear good fruit ; while 

 within a few miles, on strong deep loams, the fruit is fair and 

 beautiful the trees healthy and luxuriant. 



In the second place, it arises from the constant propagation 

 of the same stock ; a stock becoming every year more and more 

 enfeebled in those localities by the unfavourable soil and climate. 

 No care is taken to select grafts from trees in healthy districts, 

 and this feeble habit is thus perpetuated in the young grafted 

 trees until it becomes so constitutional, thatjin many cases, trees 

 sent from the sea- board into the interior will carry the degene- 

 rate habit with them, and are often many years in regaining 

 their normal state of health.* 



To add force to this view, we will add, that we have had the 

 satisfaction lately, of seeing trees of the condemned varieties 

 taken from healthy interior districts to the sea- board, where 

 they have already borne fruit as fair and unblemished as evei ; 

 thus proving that the variety was not enfeebled, but only so 

 much of it as had been constantly propagated in a soil and cli- 

 mate naturally rather unfavourable to it. While in favourable 

 positions it maintained all its original vigor. 



But there is another interesting point in this investigation. 

 Do the newly originated sorts really maintain in the unfavour- 

 able districts the appearance of perfect health ? Are the nev 

 pears uniformly healthy where the old ones are always feeble ' 



Undoubtedly this question must be answered in the negative 

 Some of the latest Flemish pears already exhibit symptoms of 

 decay or bad health in these districts. Even Mr. Kenrick, with 



The tree, apparently healthy in the spring, blossoms, and sets a crop of 

 fruit. Towards midsummer its leaves are disfigured with dark or black 

 spots, and except a few at the ends, fall from the branches. The fruit is 

 covered with black specks, often ceases growing when at half its size, and 

 in the worst cases the skin becomes hard, cracks, and the fruit is entirely 

 worthless. This rusty and diseased state of the skin, is caused by the at- 

 tack of a. minute species of fungi (Uredo, Puccinia, etc.), which fasten 

 upon, or are generated in vegetable surfaces in a languid state of health. 



* A skilful cultivator in Ohio informed us of a case in point. Some 

 years ago he planted two Doyenne pear trees both apparently healthy One 

 was from the sea-coast, the other from Western New York. The fruit of 

 the former when it came into bearing, cracked and showed all the symp- 

 toms of decay common where it came from. The other always bore fair 

 fruit. After several years careful treatment, he has at last restored it to 

 the original health of the variety. 



