A POSSIBLE INDICATOR OF SHAKE IN OAK - RELATIONSHIP BETWEEN FLUSHING DATES AND VESSEL SIZES

Previous work by Savill (1986) has shown that oak trees (Quercus robur and Q. petraea) with large earlywood vessels appear to have a much greater predisposition to shake than trees with smaller vessels. The aim of the investigation described here was to determine whether there are any externally visible characteristics correlated with vessel size, so that shake-prone trees can be recognized in the field. It was found that trees that flush latest within a population tend to have the biggest vessels. Possible reasons for this correlation are discussed briefly. The finding has the practical value that oaks which are predisposed to shake can be marked at flushing time and removed in thinning operations. © 1990, Oxford University Press. All rights reserved.