Bending strength of small diameter woody roots of apple rootstocks in relation to poor anchorage

A non-linear relationship was recorded between load at failure and root cross-sectional area for 3 types of roots. It can be concluded, as might be expected that apple roots of smaller diameter bend very easily compared with the roots of larger diameter. Some limitations to the testing bending strength were encountered. The method used was essentially similar to that used in measuring the strength of apple flesh. The smallest diameter roots were slip from the brass rod during testing. The roots of > 2 mm diameter, (overbark measurement) were however, amenable to testing using this technique. Despite this, the method used, appeared to be free from major problems and was simple enough to use for a large number of roots.