(formerly Lactuca muralis)
Wall-lettuce is an opportunistic weedy species that may be found in disturbe soils that are moist in the spring and into the early summer. It is common along roadsides, in rock pits and gravel quarries, and fallow fields.
A native of northern Europe, wall-lettuce has become established in various locations in the northeastern US and southeastern Canada as well as southern British Columbia and in widespread locations to the west of the Cascades from the Puget Trough south to the Willamette Valley and mountains to the north of Roseburg, OR. It is fairly abundant along roads in the western Cascades of Oregon and localized on the eastern slope of the Cascades to the east of Mt. Hood.
In the Columbia River Gorge, it may be found between the elevations of 100'-1200' from the Sandy River in the west eastwards to near the Wind River. It is more rarely found as far east as the Memaloose Rest Area on Interstate 84.