suitable nesting sites. One of the largest nesting aggregations in England is in a former aggregates yard where the bees nest in a large artificial mound of sand. Even on a small scale, land managers can create bare patches close to food sources for the bees to nest in by cutting the vegetation very short to expose bare soil. In one instance, bare areas of soil were scraped out between rows of asters and were colonised by the bees, while on a larger scale, bulldozers have been used to scrape the soil free of the vegetation. References Colletidae Hymenoptera of Europe Insects described in 1943