Normally the sugar-beet root aphid, Pemphigus betae Doane, lives and feeds
on sugar-beet roots below ground during the summer and fall. However, in many beet fields between Lethbridge and Monarch, Alberta, in September, 1956, a large number of these aphids were found on the soil surface and on the crowns and leaves of the plants. Many of the aphids had crawled up the plants and, even after death, remained clinging to the leaves (Fig. 1). This clinging reaction seemed similar to that of grasshoppers infected with Entomophthora grylli Fresen. Mr. R. B. Baird, Entomology Laboratory, Canada Department of Agriculture, Belleville, Ontario, identified the organism causing the disease destroying these aphids as Entomophthora aphidis Hoffm. This is the first record of this disease killing subterranean aphids in Canada. The only other reports of E. aphidis on root aphids are those of Maxson (1916) in Colorado and Charles (1941) in California. In Canada, it has been previously reported as a factor in control of the pea aphid, Acyrthosiphon pisum (Harr.), in the Annapolis Valley, Nova Scotia (MacLeod, 1953).