That is a picture of a "girdled tree".  

Join us Saturday, April 4 at 10:00am -Shaker Lakes Conservancy Community Group Forum -Shaker Lakes -Save the Trees.  Note: PLEASE DO NOT GIVE MONEY.  It is confusing I know (this money does NOT go to the conservancy).

Where: Picnic area at Horseshoe Lake Park     Followed by:  An optional walk around the lakes

This is what we need to save. Plans are in play to further damage Horseshoe Lake, Drain the Lower Lake, Bulldoze 26 acres, and Cut Down 1072+ large trees (plus many smaller ones)

This essay explains a lot:  

So, about those thousand (mostly native and healthy) trees at Horseshoe Lake.....https://shakerlakes.blogspot.com/