FROZEN-SAP BLIGHT. 827 



not more liable than many others. The Seckel pear is cele- 

 brated for its general freedom from blight, which we attribute 

 entirely, to its habit of making short jointed shoots, and ripen- 

 ing its wood very early. 



To distinguish the blight of the frozen sap from that caused 

 by the attack of the Scylotus pyri, is not difficult. The effects of 

 the latter cease below the spot where the insect has perforated 

 and eaten its burrow in the branch. The former spreads 

 gradually down the branch, which, when dissected, shows 

 the marks of the poison in the discoloration of the inner 

 bark and the pith, extending down some distance below the ex- 

 ternal marks of injury. If the poison becomes largely diffused 

 in the tree, it will sometimes die outright in a day or two ; but 

 if it is only slightly present, it will often entirely recover. The 

 presence of black, dry, shrivelled spots of bark on the branches, 

 or soft sappy spots, as well as the appearance of thick clammy 

 sap in winter or spring pruning, are the infallible signs of the 

 frozen-sap blight. 



The most successful remedies for this disastrous blight, it is very 

 evident, are chiefly preventive ones. It is, of course, impossi- 

 ble for us to avoid the occasional occurrence of rainy, warm 

 autumns, which have a tendency to urge the trees into late second 

 growth. The principal means of escaping the danger really lies 

 in always studiously avoiding a damp soil for the fruit tree. Very 

 level or hollow surfaces, where heavy early autumnal rains are 

 apt to lie and saturate the ground, should also be shunned. And 

 any summer top dressing or enriching, calculated to stimulate 

 the tree into late growth, is pernicious. A rich, dry soil, is, on 

 the whole, the best, because there the tree will make a good 

 growth in time to ripen fully its wood, and will not be likely to 

 make second growth. A rich, moist soil, will, on the contrary, 

 serve continually to stimulate the tree to new growth. It is in 

 accordance with this, that many persons have remarked, that 

 those pear trees growing in common meadow land, were free 

 from blight in seasons when those in the rich garden soils were 

 continually suffering from it. 



The first point then should be to secure a rich but dry, well 

 drained soil. Cold aspects and soils should be avoided, as likely 

 to retard the growth and ripening of the wood. 



The second is to reject, in blighted districts, such varieties as 

 have the habit of making wood late, and choosing rather, those 

 of early habit, which ripen the wood fully before autumn. 



Severe summer pruning, should it be followed by an early 

 winter, is likely to induce blight, and should therefore be avoid- 

 ed. Indeed, we think the pear should always be pruned in 

 winter or early spring.* 



* The only severe case of blight in the gardens here, during the summer of 

 1844, was in the head of a Gilogil pear a very hardy sort, which had never be- 



