To view and download the official document (see Tree Defects -Part A, B, C) :

However, this html version has higher quality images.

Tree Defects:  A Photo Guide

Alex L. Shigo
US Forest Service General Tech. Report NE-82; 1983; 167 pages

Click here for inside cover.

Page 1-31

Page 32-61

Page 62-91

Page 92-121

Page 121-151

Page 152-167

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