512 
J. G. GROSSENBACHER 
Fig. 45. Twelve-year-old apple tree which had a complete girdle of loose 
bark from the ground up to the main branches. A radial cleft 25 cm. long occurred 
in it near ground. 
Fig. 46. Apple tree with complete girdle of dead bark; thick callus along its 
upper edge. 
Fig. 47. A typical case of crown-rot on apple. 
Fig. 48. Stem of orange tree showing radial clefts in loose bark. Initial 
injury occurred on the night of November 20, 1914, when the temperature sank to 
a little below — 2° C. In the summer of 1915 many trees affected in this manner 
died with symptoms of "withertip." 
Plate XXVII 
Crown-rot and other troubles of large trees. 
Fig. 49. Section from near the base of a large apple-tree trunk (28 cm. in 
diameter), showing a line of initial injury that occurred some fourteen years before 
cutting; also showing that the bark sustained a radial cleft (upper side). 
Fig. 50. Section of another tree of the same size and from the same orchard 
as that shown in Fig. 49. The initial injury occurred in the same year as that in 
Fig. 49. The wood cylinder subsequently died and rotted, and some of the wood 
produced by the new cambium also decayed. 
Fig. 51. Large apple tree with complete crown-rot girdle. Upper roots died, 
but those under the center of the tree were alive. 
Fig. 52. Section of a spruce stem, copied from Hartig (Untersuch. Forsthot. 
Inst. Miinchen i: 147. 1880). Included here to show that the initial injury from 
which the trouble developed occurred during the dormant season and not during the 
growing season as was maintained by Hartig. 
