Renter: Existing cavities. Nests in existing cavities (eg beetle emergence holes). This species has been reared on many occasions from nests in dead, broken and dry Rubus stems (e.g. F. Smith, 1876 [as Prosopis perforator]; V.R. Perkins, 1892; Chambers, 1949; Danks, 1971b; Janvier, 1972a; material in various collections).
The following account summarises the observations of Danks (1971b). The female usually excavates its own linear nesting burrow, which is generally about 70 mm, but up to 125 mm, in length. She constructs up to 14 cells per nest, there being no difference in size between male- and female-producing cells (male cells are invariably placed nearer the nest entrance). Cells vary between 4-7 mm in length and 2 mm in diameter. Some pith is often incorporated into cell partitions. A nearly spherical vestibule with a diameter of 2-3 mm is common to most nests. When completed, a cell is usually two-thirds filled with provision, and an egg laid on top of this. The larval feeding period occupies about two weeks, and the larva tends to sink into the provision as it develops. Danks also describes and figures the prepupa.
In the Netherlands, V. Lefeber (pers. comm.) reared examples from burrows in Laburnum wood and a Sambucus stem. Peeters, Raemakers & Smit (1999) also list nests in Fraxinus excelsior stems.