Killing of Plant Tissue by Low Temperature 



207 



The following table gives the result of freezing twigs: 



Table 23. Showing Killing Temperature of Twig Tissue at 



Different Seasons. 



Variety 



PEACHES 



Elberta 



Elberta 



Young Champion. 



Champion. 



Belle of Georgia 

 five years old . 

 Elberta 



Elberta, 



one year old. 



Seedling peach, 



one year old . 



Elberta 



Elberta. 

 Elberta. 



Elberta . 



Elberta . 



Elberta . 



Elberta. 



Elberta. 



Results 



July 6,'13 

 July 17, '13 

 July 29,'12 



Aug. 5,'12 



Aug. 29,'12 

 Sept. 24,'12 



Oct. 5,'12 



Oct. 8,'12 

 Oct. 14,'ll 



Oct. 19, '11 

 Oct. 21, '11 



Oct. 26,'ll 



Nov. l,'ll 



Nov. 2, '11 



Nov. 16,'12 



Dec. 6,'12 



Seedling, 



one year old iDec. 18, '12 



Seedling, one year old Dec. 19, '12 



Elberta. 



Dec. 7,' 12 



i:iberta Jan. 11, '13 



Rice's 



Seedling Jan. 25, '12 



Elberta 'Mar. 2 1, "13 



Rice's 



Seedling Mar. 21, '13 



Elberta lApr. 5. '13 



6 



5 

 5 



- 5 



- 5 



- 9.5 



- 5 I 



- 7.5] 



- 9 



- 9 



- 9 



-IS 

 -15 



-16.5 



-18 



-16 



-20 



-19.3 

 -18 



-18 

 -12.5 



13 twigs. Cambium dead in 5; 



cambium and cortex in 8. 

 20 twigs. Cambium and cortex 



dead in all. 

 Twigs 10" long. All tissue injured 



in terminal 6"; slight injury to 



cortex only at base of tree. 

 Bark and cambium killed in all 



stems. 

 Bark, cambium and sap wood 



killed in all twigs. 

 Bark, cambium, and outer portion 



sap wood killed. 

 Cambium and cortex injured except 



at base of one twig. Only injury to 



sap wood was in terminal part of 



one twig. 

 Twigs injured in cambium and 



cortex region. 

 24 twigs. 100% dead. Cambium 



only killed. 



38 twigs. No injury. 



46 twigs. 73.9% dead. Cambium 

 only killed. 



39 twigs. Killing confined largely 

 to cambium. 



23 twigs. 60.6% killed. Cambium 



only injured. 

 51 twigs. 84.3% killed. Cambium 



only injured. 

 Slight injury in cortex. Cambium 



uninjured. 

 Cortex injured in all; cambium un- 

 injured; pith killed and sap wood 



occasionally showed injury. 



Injured slightly in cortex and pith; 



cambium and wood sap uninjun-d. 

 Injury confined to pith and cortex. 

 Injury confined to shoulder below 



bud and pith region. 

 Pith (lead, oiIrt tissues uninjured. 

 Cortex injured slightly; cambium 



entirely killed. 

 Injury to sap wood and pith. 

 Injury to sap wood and [)ith less 



than with Elberta. 

 Wood uninjured. 



