Not all firewood is created equal. Some species of trees are able to produce much more heat per cord of wood. A cord is the amount of wood in a well-stacked woodpile measuring four feet wide by eight feet long by four feet high. 

Following are heat values (in million BTUs) per cord for various species of trees. The higher the value, the better the wood:  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 (hedge) - 32.6 (sparks, do not use in open fireplace); sycamore - 19.5 (difficult to split); walnut, black - 21.8.          

The Kansas Forest Service has a publication titled “Managing Your Woodland for Firewood” that is quite helpful. See  www.ksre.ksu.edu/bookstore/pubs/mf773.pdf.   

Remember to obtain firewood locally. The emerald ash borer has spread in Kansas primarily because of transported wood. 

Stacy Campbell is an Agriculture and Natural Resources agent for Cottonwood Extension District. Email him at scampbel@ksu.edu or call the Hays office, 785-628-9430.