Certain tree varieties produce firewood that gives off more heat than others. Osage orange, honeylocust, black locust, bur and post oaks all have high heat values. However, osage orange firewood tends to spark which can be dangerous, especially in an open fire. If you’re harvesting your own firewood, it is beneficial to note wood from certain species, such as black locust and elms, is difficult to split.
The Kansas Forest Service has published a great resource for landowners about this topic: “Managing your Woodland for Firewood”.
Homeowners who plan to purchase firewood should buy local to avoid spreading pests including Emerald Ash Borer. The chart below ranks the woodland species in terms of the heat value (measured in British Thermal Units, BTUs) per cord of wood. A cord is the amount of wood, stacked well, in a pile that measures 4 feet wide by 8 feet long by 4 feet high. Higher BTU values indicate more heat produced. (Cynthia Domenghini)
Tree Variety | BTU | |
Ash, Green | 22.8 | |
Cottonwood | 15.9 | |
Elm, American | 19.8 | Difficult to split |
Elm, Red | 20.6 | Difficult to split |
Elm, Siberian | 20.9 | Difficult to split |
Hackberry | 21.0 | |
Honeylocust | 25.6 | |
Locust, Black | 28.3 | Difficult to split |
Maple, Sugar | 24.0 | |
Maple, Silver | 18.9 | |
Mulberry | 25.3 | |
Oak, Red | 24.0 | |
Oak, Bur | 24.9 | |
Oak, Post | 25.6 | |
Osage Orange | 32.6 | Tends to spark |
Sycamore | 19.5 | Difficult to split |
Walnut, Black | 21.8 |
Cynthia Domenghini, Instructor and Horticulture Extension Specialist