Head of social enterprise development and training at Camden Garden Centre, Mike Jackson, wrote in Horticulture Week's General Discussion Forum he was seeing more and more trees damaged by dogs goaded by their owners to rip off bark from trees.
Jackson added: "I've seen several trees completely ring barked, which will of course kill the tree."
Several posters on the forum thread suggested publicity campaigns to educate park visitors. Horticulturist Philip Turvil suggested "interpretation signs, consultation and tree days".
Paul Harris said he had dealt with the issue recently. Two trees - a young lime ring barked and an alder - in west London had been "completely vandalised" and "torn and shredded".
Maurice Barnes has had to replace several specimens this year due to dog damage and suggested the use of Abies, with its off-putting sap, might be a solution.
Mark Smith in Derby suggested raising the crowns on trees with low branches, and Geoff Parsons suggested railings, fences, chemical or natural deterrents and even lion dung might keep dogs at bay.
Join the discussion at http://community.hortweek.com/forums/t/576.aspx.