TACF is developing advanced hybrids and building on the work of earlier breeders to improve tree form while enhancing resistance.
[citation needed]Grafts from large survivors of the blight epidemic were evaluated following inoculations, and controlled crosses among resistant Americans were made beginning in 1980.
[citation needed] It appears that inheritance of resistance requires genes of two trees with good combining ability from each source location.
More generations of controlled crosses may be required to make American chestnuts produce blight resistance that is regularly inherited by seednuts.
Some of this time may be saved by utilizing grafts, and further progress may result from Elkins' studies underway which is trying to locate chemical markers for resistance.