Gilman, E.F., and G. Knox. 2005. Pruning type affects decay and structure of crapemyrtle. Journal of Arboriculture 31:38–47. Established Lagerstroemia × Natchez trees were topped, pollarded or unpruned for four years. Topping resulted in more dead stubs and discolored wood than pollarding which had limited decay development. Recommended developing pollards rather than routine topping. Nice photos. Florida US.
Neilsen, W., and E. Pinkard. 2003. Effects of green pruning on growth Pinus radiata. Canadian Journal of Forest Research. 33:2067–2073.Crowns of 6- to 8-year-old, plantation Monterey pine were raised. Raising to 45% of tree height had no effect on growth which was reduced with greater crown removal. Suggests maintaining a live crown ratio of 55%. Tasmania Australia.
Schwarze, F., J. Gruner, M. Schubert, and S. Fink. 2007. Defence reactions and fungal colonization in Fraxinus excelsior and Tilia platyphyllos after stem wounding. Arboricultural Journal 30:61–82.Describes the anatomy of the barrier zone (= CODIT wall 4), suggesting that differences in this zone account in part for species differences in decay resistance. Strong within species variation in discoloration associated with both increment borer holes and chain saw cuts to the stem. Also isolated fungi from around the wounds. Excellent photos. Good discussion of fungal development and tree response. Freiburg Germany.
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