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niOTECTION OF FRUIT TREES AGAINST WALLS. 



The iron and glass protecting frame by Messrs. Cottam and 

 Hallen was not completed wlien the severe frost was experienced. 

 The foliage under it is at present (June 1) very healthy, and 

 does not appear checked like that exposed to the cold nights in 

 the end of May. 



From what has been observed, the facts are ascertained that a 

 thin straw screen will protect peach-trees in blossom from the 

 effects of twelve degrees of frost ; that coping-boards will be 

 sufficient for about four degrees ; that a conuuon net (not woollen), 

 aided by coping-boards, was insufficient compared with straw 

 screens ; that sashes, in a nearly horizontal position, covered 

 with a mat, but with a 3-inch opening at the back of the frame, 

 and a perforated zinc plate in front, were likewise insufficient, the 

 peaches suffering as much, or more than those on the open wall 

 with coping only. 



Straw having proved so efficient, probably owing to its being 

 hollow, and, confining in its interior a quantity of air, a slow 

 conductor of heat, it seems desirable that it should be manufac- 

 tured so as to preserve, in great measure, its tubular form, and 

 have a neat appearance. 



