Killing of Plant Tissue by Low Temperature 



213 



Variety 



Jonathan apple, 

 four years old, 



Jonathan apple, 

 four years old 



Jonathan apple, 

 four years old 



Jonathan'apple, 

 four years old 



Jonathan apple, five 

 years old. (Thickest 

 part of trunk, 3 in. 

 in diameter) 



Same 



Same 



Same 



Jonathan apple, five 

 years old. (Thickest 

 part of trunk, 3 in. 

 in dia.) 



Same 



Same 



Jonathan apple, five 

 yearsold. (Thickest 

 part of trunk, 3 in. 

 in dia.) 



Same 



Nov. 14/12 



Nov. 14,'12 



Nov. 14,'12 



Nov.44,'12 



Jan. 15, '13 

 Jan. 15, '13 



Jan. 15/13 



Jan. 15/13 



Jan. 15, '13 

 Jan. 15, '13 

 Jan. 15, '13 



Jan. 

 Jan. 



20,'13 

 20,'13 



Same Jan. 20,'13 



Jonathan apple, five 

 yearsold. (Thickest 

 part of trunk, 3 in. 

 in diamcterj ijan. 20, '13 



-12 



-12 



-12 



-12 



-20 

 -20 



-20 



-20 



-20 

 -20 

 -20 



15, 

 15, 



-15.5 



-15.5 



Location 



of 

 Tissue 



At ground. 



6 in. above ground 



12 in.' above ground 



18 in. above ground 



At crown , 



3 in. above crown 



At level of ground. 



3 in. above ground 



6 in. above ground . 

 12 in. above ground 

 18 in. above ground 



At crown 



3. in. above crown 



At ground. 



3 in. above ground 



Results 



Most severely 

 injured. Cam- 

 bium cortex 

 and sap wood 

 injured. 

 Cambium in- 

 jured. Cor- 

 tex slightly 

 injured. 



Cambium in- 

 jured. Cortex 

 slightly in- 

 jured. 



Cambium in- 

 jured. Cor- 

 tex slightly 

 injured. 



All tissue in- 

 jured severe- 



ly. 



All tissue in- 

 jured. 



Slight injury 

 in bark; none 

 in cambium; 

 sap wood in- 

 jured. 



Injury in same 

 tissue as 

 above, but 

 not quite so 

 severe. 



Same as above. 



Same as above. 



No injury in 

 cortex or cam- 

 bium; sap and 

 heart wood 

 slightly in- 

 jured. 



All tissue in- 

 jured severe- 



All tissue in- 

 jured slightly 

 less than 

 above. 



Injury in cor- 

 tex region. 



Slight injury 

 in cortex 

 region. 



