132 ^ff''^^^ of Frost on Dormant Vegetation. [March, 



. J . 



suffer, even in Siberia, where, as at Yakutsk, the ground is perpetually 

 frozen to the depth of four hundred feet, and which the few months of 

 Bummer can not thaw to a greater depth than three or four feet ; and yet, 

 says Erman,=-'= " vegetable life continues not merely uninjured, but favored 

 in the highest degree by the equable and very rapid increase of heat." 



In the colder regions of our own country, it is by no means uncom- 

 mon for large trees to be cleft from top to bottom on one side, in severe 

 weather, with a very loud report. This is, no doubt, caused by the 

 contraction of the wood already frozen, by its sudden subjection to a 

 more intense cold. These cracks generally close up when the weather 

 moderates, producing merely a " shake " in the tree, unfitting it for 

 lumber. In many cases of this kind which have come under my own obser- 

 vation, I have never known a single tree so split, to be killed by the 

 intensity of cold. 



Several years ago, when living in Xorfchern New York, we received a 

 lot of young fruit trees too late in the winter to set out ; they were 

 placed in a room the temperature of which was repeatedly during the 

 winter as low as 20° below zero. They were thoroughly frozen, root and 

 branch, and yet when planted, the usual proportion of them lived. The 

 same result in trees taken up and transported has been noticed by others. 



Many instances might be added to the above, but it would be need- 

 lessly occupying your pages, as I think enough have been given to con- 

 vince any one that the mere freezing of plants in winter will not destroy 

 their vitality. 



Our wonder at this is greatly diminished, when we consider that even 

 some forms of animal existence possess, the same power of retaining 

 vitality when they have been completely frozen. Frogs, reptiles, and 

 some species of fish, can be resuscitated after having been frozen for a 

 length of time. Grubs, caterpillars, the larvce of insects, the ova of the 

 silk worm and other low forms of animal existence exhibit the same 

 phenomena. I have repeatedly frozen trout, perch, and pickerel, after 

 they had been caught with the hook, to such an extent that their fins on 

 being bent would snap off like glass ; and yet, on being thawed, a ma- 

 jority of them revived ; and those that did not were either injured by the 

 hook or exposed in the air so long as to kill them before they were frozen. 

 Such being the case, how much the more ought we to expect to find a 

 much greater power of resistance under an intense degree of cold in 

 plants, whose functions of vitality, though perfect in themselves, are not 

 of as high an order as those of animals ? 



•■■Travels in Siberia, Am. Ed., vol. 2. p. 279. 



