Beetle (IMAGE) U.S. Geological Survey Caption The mountain pine beetle is much smaller than this image -- about 5 millimeters or the size of a grain of rice. Credit Courtesy S.D. Department of Agriculture. Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.