Their blood stained the trees and never washed off. [contrarian]
Standing next to a tree with red frozen sap on its bark would bring flashbacks of the many times we executed prisoners by tying them to trees and shooting them. Their blood stained the trees and never washed off, even during the rainy season.
Farrar, Straus and Giroux Ishmael Beah, A Long Way Gone- Memoirs of…, loc. 764