Callus Hair Growth (IMAGE) Norwich BioScience Institutes Caption Scanning Electron Micrograph of Fuji apples showing extensive branching of callus hairs. Credit Mary Parker, IFR 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.