https://creativecommons.org/publicdomain/zero/1.0/https://www.rawpixel.com/image/8802580Edit ImageSaveSaveEditCropCustom TextForesters chip base of trees to inspect cambium (a protective layer between bark and inner wood). If this is damaged, tree cannot survive and will be marked to cut, September 1973. Photographer: O'Rear, Charles. Original public domain image from FlickrMorePublic DomainFree CC0 image for Personal and Business useInfoView CC0 LicenseJPEGSmall JPEG 808 x 1200 px | 300 dpiLarge JPEG 2021 x 3000 px | 300 dpiFree DownloadForesters chip base of trees to inspect cambium (a protective layer between bark and inner wood). If this is damaged, tree cannot survive and will be marked to cut, September 1973. Photographer: O'Rear, Charles. Original public domain image from FlickrMore