The dried wood of osage orange is prized for firewood as it has the highest BTU on charts that rank that property among native trees. It’s resistant to rot due to its density and wood remains usable for years in a firewood pile. As firewood it gives off so much heat that persons using woodstoves are warned to use it sparingly as the intense heat it produces has warped certain of those metal heaters. The fruits, too, are slow rot as they are full of latex and shunned by almost all animals as food. The latex, also in the wood, makes this wood unsuitable to burn in an open fireplace as the incredible number of sparks burning logs produce would be a danger. Even in a woodstove, keep the door closed so sparks won’t fly around.
Osage orange wood burns intensely

SC Public Radio