194 



Missouri Agr. Exp. Sta. Research Bulletin No. 8 



Material 



Cabbage, 



Red Rock.. . 

 Cabbage, 



Red Rock. . . 

 Cabbage, 



Red Rock . . . 



Tomatoes 



Tomatoes 



Tomatoes 



Elberta 



peach leaves. 

 Elberta 



peach^leaves. 

 Elberta 



peach leaves. 

 Elberta 



peach leaves. 

 Late Duchess 



apple leaves.. 

 Late Duchess 



apple leaves.. 

 Late Duchess 



apple leaves.. 

 Late Duchess 



apple leaves.. 



Manner 



of 

 Thawing 



Rapidly in room 



Slowly in freezer 



Rapidly, fanned. 

 Rapidly in room 

 Slowly in freezer 

 Rapidly, fanned. 



Rapidly 



Slowly 



Rapidly 



Slowly 



Rapidly 



Slowly 



Rapidly 



Slowly 



Date 



June 30,'13 



June 30,'13 



June 30, '13 

 June 28,'13 

 June 28,'13 

 June 28,'13 



July 16/13 



July 16,'13 



July 17,'13 



July 17,'13 



July 16,'13 



July 16,'13 



July 17,'13 



July 17,'13 



Per- 

 cent- 

 age 

 all 

 Killed 



40.0 



60.0 



60.0 

 100.0 

 100.0 

 100.0 



44.4 



0.0 



0.0 



0.0 



0.0 



0.0 



0.0 



0.0 



Average, Leaves of succulent plants, thawed slowly. 

 Average, Leaves of succulent plants, thawed rapidly 

 Average, Same, excluding lettuce, thawed slowly. . . . 

 Average, Same, excluding lettuce, thawed rapidly... 



Per- 

 cent- 

 age 

 Total 

 Sur- 

 face 

 Killed 



65.0 



65.0 



70.0 

 100.0 

 100.0 

 100.0 



58.9 



25.0 



17.9 



18.9 



28.4 



19.7 



27.4 



26.3 



68.4 

 76.3 

 74.4 

 76.2 



In none of these plants, except lettuce, does there seem to be 

 any difference in the amount of killing on account of the rate of thaw- 

 ing. Lettuce, however, seems to have the amount of injury reduced 

 by slow thawing. Even with lettuce, however, a slight reduction 

 in temperature, certainly not more than one degree, would offset the 

 eflfect of slow thawing. 



Effect of Wilted Condition on Killing Temperature. The condi- 

 tion of plant tissue at the time of freezing with reference to turgidity 

 seems to have something to do with the killing. In all freezings 

 care has been taken to have all of the plants kept in an equally turgid 

 condition, or as nearly so as it was possible to maintain, though to 

 find to what extent slight difference in turgidity might alter results, 

 a considerable number of plants were frozen, some turgid and some 

 wilted. The following table gives a list of freezings and the results: 



