Potted olive trees (IMAGE) University of Cambridge Caption Ornamental olive trees imported for sale in the UK can be over 100 years old, with many hiding places amongst their gnarly bark and the soil they’re transported in. This is incredibly risky in terms of importing pests. Credit Silviu Petrovan/ University of Cambridge Usage Restrictions With credit License Original 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.