Streams that dry during part of the year are common throughout the world, yet studies of themacroinvertebrate assemblages in these types of streams are rare compared to those in permanentstreams; and studies that assess the effects of agriculture on temporary stream invertebrates are evenrarer. We studied macroinvertebrate assemblages in lowland temporary streams of a region with highagricultural land use, the southern Willamette Valley, Oregon, USA. Overall assemblages were dominatedby non-insects, and invertebrates tolerant of organic pollution.