Roford 1955 Cynomys ludovicianus January 2, 1959. Nw.Ft. Collins, Colorado. one spot trailer showed that green Opuntia (prickly pear) leaf had been chewed - 3" long chewed edge. Apparently there, considerable activity around Jan. 1 at 5000' elev., but not every day. January 3, 1954 Talked with John L. Pitzner, soils man of the Front Range Cyp. Station, concerning soil and rodents. He was very much interested in my problem. He could see no possible harmful effects and some possible good effects of rodent workings. The important soil features for which to look are texture, slope, and impermeable layers, such as hardpan, in his estimation. He would be interested in working on soil in Cal. colonies personally in the field as well as in his lab. (There are many excellent soil men at Cal. A & M, in S.C.S. and in Agronomy Dept.). || In afternoon drove with V.B. Scheffer to the prairie dog town near Wellington. Only a few patches of snow remained there. "Charlie" and at least 10 other C. L. seen. I took several plates of an immature that was even taller than Charlie. This one to whom corn that was thrown near him it could be approached to a distance of 10'. Shallow holes about 2" deep dug at many spots near burrows as if digging for some sort food (no remains found). While Vic was photo- graphing Charlie, who was "thin out of burrow," C. set up a series of balls, increasing in speed, each followed by an internal grunt. Many burrows, some showing many fresh tracks, up to 100 yds. W. of the