PEAR BLIGHT AND HONEY DEW. 455 



they grow ; neglect this, and they will be barelegged, nothing but naked wood at 

 the bottom, and totally unfit to show singly, even on your own shelves. What is 

 the consequence ? When you arrange your greenhouse for the winter, you crowd 

 them, to hide their naked stems, and make bad worse. They may make a pretty 

 bank of flowers, because you see nothing but their tops ; whereas, prune them 

 every year before they make their new wood, keep them well down, for the top 

 eye or bud left is sure to grow the most vigorously, and for this you must make 

 allowance when cutting back or pruning. As, therefore, you must, properly speak- 

 ing, begin in the spring, prune everything as it goes out of flower; Hoveas, Acacias, 

 Camellias, Correas, Chorozemas, Cytissus, Oestrum, Epacris, Nerium, Fimelia, 

 and many others." 



PEAR BLIGHT AND HONEY DEW. 



BY YARDLEY TAYLOR, LOUDON COUNTY, VIRGINIA. 



Is there any connection, either in cause or effect, between blight in pear-trees and 

 the substance called honey dew ? We have had both here, to an unusual extent, 

 and the latter more largely on pear-trees than any other, though found on almost 

 all kind of trees. I have two large pear-trees, planted more than thirty years ago 

 (one a wilding), brought in from the fields when small, and planted in the orchard. 

 This has grown freely, and was never affected with blight till this season, and now, 

 large upper limbs, near two inches in diameter, are dead ; two of the branches 

 grafted, of late years, with the Bergamot and White Doyenne, are somewhat affected, 

 but not so badly. The other tree was an ordinary fall pear, grafted on the root 

 of a white thorn, and is probably now mostly on its own roots, as the graft was 

 inserted beneath the surface of the ground, and the tree has grown freely but not 

 rapidly. This is scarcely touched with the blight, except some of its upper 

 branches that have been grafted latterly with other varieties, to bring them into 

 early bearing. This tree exhibited the substance called honey dew, to a greater 

 extent than I ever noticed before ; the young shoots of the present year, the stems 

 of the leaves, and the surface of the leaves themselves, in many places were lite- 

 rally covered with it, and it fell in drops to the ground. We have about one 

 hundred varieties of pear now planted within the last ten years, and all exhibited 

 this substance more or less. Even the forest-trees showed it on their leaves to an 

 unusual extent, this season. 



But what is honey dew ? and has the cause of its production anything in com- 

 mon with what we may suppose to be the cause of the pear blight ? Without 

 assuming the affirmative, it might be well to examine the sul)ject a little, and 

 obtain what light we can on this or any other subject connected with vegetable 

 growth. The most plausible theory that has occurred to me, is this : We know 

 that in almost, if not quite all trees, the first flow of sap, in the si)ring, contains 

 saccharine matter ; this appears to be elaborated in the pores of the wood, from 

 the matter brought up by the sap previous to the suspension of the circulation by 

 cold. A long, regular cold winter, is most favorable for its production ; hence 

 the region 2"^ or 3° north of us, is better for sugar making from the maple than 

 this latitude. But this winter here, has been, for length and for cold, more severe 

 than they often have there, thus producing more saccharine matter here, in trees, 

 than usual. The past winter has been one remarkable for sugar making in the 

 Northern States. This saccharine matter, in the sap particularly, when abundant, 

 ht be supposed to obstruct the circulation, and even if not sufficiently to 

 the blight, it at least does so enough to cause the leaves to fall off. 



