11. Sarah Doubt discovered that ethylene stimulated abscission in 1917. 12. Abscisic acid owes its names to its role in the abscission of plant leaves. 13. In 2009 her Abscission series of installations took place during the Edinburgh Fringe Festival. 14. :The shedding is a form of abscission . 15. Researchers believe they can solve both problems with an effective abscission chemical, he said. 16. White pine boughs, showing annual yellowing and abscission of older foliage in the autumn. 17. Premature leaf abscission has been shown to occur in response to infestation by gall aphids. 18. In claws, this results in an abscission layer, and the old segment breaks off. 19. This natural shedding is called abscission . 20. However, during the pre-abscission phase, the metabolic levels of a leaf are high.
