Root age influences failure location in grass species during mechanical testing

Abstract Aims Root tensile tests are often rejected if failure location is outside the middle section of samples. This study aims to identify where and why occurs along a root axis, hence revisit current approaches test-validity. Methods Roots from Festuca arundinacea; Lolium multiflorum; perenne were sampled field-grown plants. tested using universal testing machine. samples randomly allocated into two groups for testing. Group 1 roots orientated with older tissue closest top clamp, group 2 oppositely. Tensile strength, Young’s modulus recorded each sample. Results multiflorum thinner stronger than arundinacea. Failure in depended significantly on age 75% failing younger third regardless orientation frame. Only 7% failed Conclusions Fibrous tension observed consistently fail axis. Exclusion which region axis needs re-evaluation range species.