475 3-foot elm logs, 3 1/2-8 1/2 in. in diam., were cut at approximately 2-week intervals Apr. 25-Sept. 15 and placed horizontally on racks 3 ft. above the swamp floor in different degrees of shade, at different stations. Logs of 4 summer cuttings were placed with each of the previous cuttings as check logs. The April 25 and May 15 cuttings averaged 40.5 and 50 Hylur-gopinus per log; the rest of the cuttings averaged 0-5. The Aug. 1 cuttings averaged 19.9 Scolytus per log, the others 02-12. Logs in heavy shade attracted the most Hylurgopinus; those in semi-shade the most Scolytus. Vertical logs on racks attracted half as many Scolytus as horizontal logs. Individual logs remained attractive to beetles longer than a whole cutting. Under proper conditions isolated logs were about as attractive to Hylurgopinus as a group. Logs in clearings under lath shelters did not attract beetles. Paraffining logs did not increase beetle infestation. There did not seem to be a correlation between moisture and infestation. No standing trees were attacked the first summer girdled. A difference of 3 1/2-8 1/2 inches in the diameter of a log did not influence either Hylurgopinus or Scolytus infestation.