Excavator: Ground. Trachusa laeviventris is unusual for an Anthidiine in two respects: not only does it nest in loose sand but also the bees often form large nesting aggregations of thousands of nests. The males treat the nest site like a lekking ground. Individual males will perch or hover over a particular landmark, on constant alert for females and driving away other males from a small patch of "airspace".
Females line the nest burrows with leaf fragments cut from Cistus salvifolius and Cistus crispus (Cistaceae)(I. Cross, in litt. 2018). Cross further reports that a common cut made by the female bees is to follow the leaf midrib. This can sometimes leave an almost straight line. The jagged cut left by a previous, aborted, attempt can be seen on the other side of the midrib. For unknown reasons, the females often abandon attempts to cut a piece off.