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exposed parts continue dormant. Sap moves in 

 roots last, and great caution should always be used 

 in pruning them. 



Many years ago Lindley said: "When a plant 

 is frozen the following effects are produced: 1st. 

 the fluids contained within the cells of tissue are 

 congealed and consequently expanded. 2d. Such ex- 

 pansion produces to some extent a laceration of 

 the sides of the cells and impairs excitability by the 

 unnatural extension to which the sides of the cells, 

 if not lacerated, are subjected. 3d. It expells air 

 from the aeriferous cavities. 4th. It also intro- 

 duces air, either expelled from the air passages, or 

 disengaged by the glacial decomposition of water 

 into parts naturally intended to contain fluid. 5th. 

 The green coloring matter, and other secretions, 

 are decomposed. 6th. The vital fluid, or latex, is 

 destroyed, and the action of its vessels paralyzed. 

 7th. The interior of the tubes, in which fluid is 

 conveyed, is obstructed by a thickening of their 

 sides." In a word, the cellular system is broken 

 up, the protoplasm is freed and the lifeless branches 

 rapidly lose their sap by evaporation. 



In dry weather a fig tree will sometimes show in- 

 jury at a temperature about two degrees above 

 freezing, its tender branches being as succulent as 

 tomato vines. This unusual sensitiveness, largely 

 from the rapid evaporation which takes place 

 through leaves and stems, is a factor in reducing 



