PEOPAGATION. 139 



and those which continue to grow late in the season. 

 Such varieties have very naturally acquired the epithet of 

 tender, especially as orchard trees of the same kinds, even 

 in a bearing state, have been similarly affected ; in some 

 sections of the country, these kinds have been thrown out 

 of cultivation. The bark looks shriveled and withered, 

 the twigs seem, dry when cut, and resist the knife ; when 

 thawed by. the iire, or on the return of spring weather, 

 the bark seems loose, and the inner bark, instead of being 

 greenish-white, becomes brown, and the whole tree looks 

 as though it was dead. In old trees, large portions of the 

 bark start from the stem and large limbs, and hang loosely 

 for awhile and then fall off. The buds alone retain their 

 vitality, and upon the return of spring they sometimes 

 succeed in establishing the necessary connection with the 

 soil, and restore the circulation of the sap ; the results are 

 the deposit of the usual annular layer of woody matter, 

 which encases the dead portions within, that become like 

 a sequestrum of dead bone in an animal. The best^treat- 

 ment for the trees that have been winter-killed, is to cut 

 them back very severely, in the hope of producing a vig- 

 orous wood-growth the next season, to repair the injury. 



A partial winter-killing often affecta small nursery trees, 

 especially on low and wet, undrained soils ; the plants re- 

 cover, but for years they have a black point in the heart 

 which embraces all of the wood-growth that was affected — 

 all their wood at the period of the disaster. Tliis is en- 

 closed and surrounded by clear, healthy wood ; but such 

 trees are not desirable, they are so fragile, as to be easily 

 broken. 



The best preventive for winter-killing in the nursery, is 



