<html><head><meta http-equiv="Content-Type" content="text/html; charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><div><blockquote type="cite" class=""><font color="#000000" class=""><br class="Apple-interchange-newline"></font><div class=""><meta http-equiv="Content-Type" content="text/html; charset=us-ascii" class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><font color="#000000" class="">Joerg,</font><div class=""><font color="#000000" class=""><br class=""></font></div><div class=""><font color="#000000" class="">This might be a good place to start, and is a relatively recent publication:</font></div><div class=""><font color="#000000" class=""><br class=""></font></div><div class=""><a href="https://www.researchgate.net/publication/283711528_The_costs_of_maintaining_and_not_maintaining_the_urban_forest_A_review_of_the_urban_forestry_and_arboriculture_literature" class=""><font color="#000000" class="">https://www.researchgate.net/publication/283711528_The_costs_of_maintaining_and_not_maintaining_the_urban_forest_A_review_of_the_urban_forestry_and_arboriculture_literature</font></a></div></div></div></blockquote></div><br class=""><div class=""><div style="margin: 0px; font-stretch: normal; line-height: normal;" class=""><span style="font-kerning: none" class="">Best,</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; min-height: 21px;" class=""><span style="font-kerning: none" class=""></span><br class=""></div><div style="margin: 0px; font-stretch: normal; line-height: normal;" class=""><span style="font-kerning: none" class="">John Martyn, Consulting Arborist</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal;" class=""><span style="font-kerning: none" class="">JPM Tree Service</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal;" class=""><span style="font-kerning: none" class="">Since 1996</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal;" class=""><span style="font-kerning: none" class="">Coquitlam, BC</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal;" class=""><span style="font-kerning: none" class="">604.789.4045</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal;" class=""><span style="font-kerning: none" class=""><a href="http://www.jpmtree.com" class="">www.jpmtree.com</a></span></div></div><div style="margin: 0px; font-stretch: normal; line-height: normal;" class=""><span style="font-kerning: none" class=""><br class=""></span></div><div style="margin: 0px; font-stretch: normal; line-height: normal;" class=""><span style="font-kerning: none" class=""><br class=""></span></div><div style="margin: 0px; font-stretch: normal; line-height: normal;" class=""><span style="font-kerning: none" class=""><br class=""></span></div></body></html>