Renter: Existing cavities. Megachile ligniseca nests in burrows in decaying wood generally, including dead trees and rotten fence posts. It has also been found occupying an iron tube. Niemelä (1936) remarks that in Finland it utilizes holes vacated by larvae of the moth Cossus cossus. In Britain, Boreham (1955a) records cells constructed from sycamore leaves. The nest has been figured by Romasenko (1990).