together. The males of both species claim territories consisting of a patch of bindweed flowers, perching on the flowers in the afternoon after a regular patrol of their little patch for errant conspecific males, which, upon countenance, they proceed to attack the intruder by ramming him from the air with a specialised protuberance on their lower abdomen. Sometimes bumblebees, honey bees or other insects are air-bombed, but never rammed. The males retreat inside the flower after the perching session, as it closes in the late afternoon, spending the night inside the flower and escaping at dawn before or after it fully closes (the females stay in underground tunnel nests). The males only land on flowers (sometimes of other plants), eschewing other perches, and feed on the nectar. Females forage for nectar and pollen in the morning and early afternoon while flowers stay open. Most copulation occurs in bindweed flowers: when a virgin female wanders into their patch, and the larger males find them busy at one of their flowers during morning patrol, the males pounce upon them without ado and immediately establish contact with their mutual genitalia, getting the job done on average 90 seconds later. These species are themselves specifically parasitised upon by the cuckoo bee Biastes brevicornis. As an invasive Outside its native range, field bindweed does not appear to be a significant threat to natural habitats. It primarily requires disturbed ground (agricultural land), and is easily shaded out by taller shrubs and trees. It may dominate the ground flora in some low quality, open grassland areas, however. In North America it can become the or a co-dominant plant in specific habitats: the low vegetation found around vernal pools in Sacramento County, and around large pools in Tehama County, California; riparian corridors in Wyoming and Colorado; aspen stands and mountain-mahogany (Cercocarpus spp.) shrubland/grassland in Colorado; and disturbed riverbank areas in the Montreal area of Canada. In some nature parks, it is commonly found in areas of disturbed soil, such as camp grounds or around horse corrals in California. Similarly, the report of its invasive character from Colorado is from former agricultural land being restored to a more natural state by The Nature Conservancy. Employees for the same organisation also reported that it was a significant weed on an irrigated plot of farmland in northern Idaho where native bunchgrass and forbs were cultivated, insofar that it caused "decreasing biodiversity"