lis cause ^ and a remedy f 07^ it. 451 



rupture the inner sap -vessels. By this, or by some un- 

 known way, the diseased sap is taken into the inner, up- 

 ward current, and goes into the general circulation. If it 

 bo in a diluted state, or in small quantities, languor and 

 decline will be the result; if in large quantities, and con- 

 centrated, the branch will die suddenly, and the odor of it 

 will be that of frost-bitten vegetation. All the different de- 

 grees of mortality result from the quantity and quality of 

 the diseased sap which is taken into circulation. In con- 

 clusion, then, where, in one class of cases, the feculent 

 matter was, in the fall, so virulent as to destroy the parts 

 where it lodged, and was then dried by exposure to wind 

 and sun, the branch above will live, even through the sum- 

 mer, but perish the next winter : and the spring afterwards, 

 standing bare amid green branches, the cultivator may sup- 

 pose the branch to have blighted that spring, although the 

 cause of death was seated eighteen months before. When, 

 in the other class of cases, the diseased sap is less virulent 

 in the fall, but probably growing worse through the spring, 

 a worse blight ensues, and a more sudden mortality. 



I will mention some proofs of the truth of this explana- 

 tion. 



1. The two great blight years throughout this region, 

 1832 and 1844, were preceded by a summer and fall such 

 as I have described. In the autumns of both 1831 and 

 1843, the orchards were overtaken by a sudden freeze 

 while in a fresh-growing state; and in both cases the con- 

 sequence was excessive destruction the ensuing spring and 

 summer. 



2. In consequence of this diagnosis, it has been found 

 practicable to predict the blight six months before its devel- 

 opment. The statement of this fact, on paper, may seem 

 a small measure of proof; but it would weigh much with 

 any candid man to be told, by an experienced nurseryman, 

 this is such a fall as will make blight ; to be taken, dur- 

 ing the winter, into the orchard, and told, this tree has 

 been struck at the junction of these branches; that tree is 

 not at all affected; this tree will die entirely the next sea- 

 son; this tree will go first on this side, &c., and to find, 

 afterwards, the prediction verified. 



3. This leads me to state separately, the fact, that, after 

 such a fall, blighted trees may be ascertained during the 

 process of late winter or early spring pruning. 



