Testing tree seeds for vigor: a review

This review examines the use of vigor tests for tree seeds. It suggests that precise eva luations of these tests and their app lication with seeds of woody p lants is not yet possib l e. This is due to the wide genetic variation, primari ly manifested in variab l e maturity and dormancy, that exists in most tree seed lots. Sensitive measurements of germination rate during standard germination tests have proved to be just as good, if not better, than any vigor test in judging the qua lity of seed lots. Acce l erated aging, leachate conductivity, and germination rate a ll show promise, but extensive tests of fie l d emergence are needed to va lidate the laboratory test procedures and interpretation.