O. Tree Commission Agendas/

THE DRIP LINE: A Missive for Those Interested in the Urban Forest 2021 August. Volume 2. Issue 8. A PERSPECTIVE FROM TEXAS: During a recent vacation to east Texas I kept one eye open for Texan urban forest condition. First, Lake Zurich’s urban forest need never to take second fiddle to any of the community urban forests that came into the view of that one eye. In fact, many communities simply relied on the default effects of any surrounding forests. Otherwise, I was struck by the difference in tree species, many of which were adapted to a subtropical climate. Further, privately owned property appeared to contribute as much to the east Texas urban forests as did community supported tree populations. One last note: There are 95 Tree City U.S.A. communities in Texas, a state with a population of 29.2 million people, while Illinois, a state with 12. 8 million has 186 Tree City U.S.A. communities; the per capita service of the Tree City U.S.A. program is approximately 4.5 times greater per community per capita in Illinois than it is in Texas. Well done, Illinois! THE URBAN FOREST AS A TEACHING TOOL: While we look upon our urban forest as a provider of a variety of environmental services, it also is a potential source of educational services. First, individual tree species are set apart in standard urban forest trees that are planted in easements making individual tree characteristics easier to assess. Yes, certainly growth habit differs between urban and endemic forest trees, but, for instance, leaf shape and the nature of tree bark do not; both prime species diagnostic characteristics. The tree species planted in any urban forest reflect latitudinal, geographic, geological, climatic, and ecological adaptations, all (relatively) easily observable in trees of any given urban forest, and this in turn forms a basis for comparison. As an extension, this process of forest comparison will clearly reveal that not all endemic species are suitable as members of the urban forest; why or why not? Good questions for students to chew on. Further, specific urban forest adaptations, managed adaptations, play a prominent role in determining urban forest membership; salt adaptation and heat abatement are two such adaptations. Finally, the managed biodiversity of the urban forest is prime in establishing an optimum livable community environment. Without managed urban forest diversity, pathogens will further reduce that diversity, at present the consequences of which are only broadly understood. The Emerald Ash Borer infestation is the latest testament to a long line of examples of urban forest pathogen invasions. Unquestionably, teachers, students, and the general public have a lot to learn from urban forests. They are an extension of who we are. CANOPY COVER AND THE URBAN FOREST: As a teenager I made a commitment to see some of the tropics during my lifetime; part of that commitment was met in a trip to Jaco Beach, Costa Rica. This area of two miles of beach flanked on either side by mountains running into the sea and backed inland up to a mile by the same range of mountains had been then recently deforested. At that time, now almost forty years ago, natives told me that the rainfall in this two square mile area had significantly decreased; forest loss had reduced transpired atmospheric water vapor, this consequently affecting cloud formation resulting in reduced clouds and therefore reduced rain. Deforestation can affect the local climate of even relatively small areas; those concerned with the urban forest should take note, as urban forests also provide that same service of enhanced atmospheric water vapor and do so in proportion to the extent of their canopy and also (of course) the specific biology of urban forest tree species. Community microclimate is important. Canopy extent also affects the pattern of rainfall reaching the ground and as a result water runoff. Ultimately in this time of climate change, the urban forest canopy will play a significant role in ameliorating adverse effects of a mismanaged climate machine. Time will certainly tell. DRIP LINE POLICY & PERSPECTIVE: The intent of this embryonic publication is to inform about pertinent issues regarding the urban forest. This intent is broad-based, and specific selection of what is or is not to appear in THE DRIP LINE will remain solely in the hands of the staff…..that would be me, Tony Harper. Also note that every effort will be made to keep the length of this missive to one page, back-to-back. The ecological perspective of this missive is bio-cultural, i.e. that we are part of the environmental system, the earth-system/world-system complex. As a consequence, there can be no us-versus-them stance with respect to what is and what is not natural; we, among the organisms of the world, are all part of the same system. As a further consequence, the topics reported on here will have the perspective of holism. Further, and this is mildly heretical, this missive takes the perspective that conservation efforts are short- term and stop-gap at best; conservation efforts, as important as they are, do NOT address the roots of our 21st Century environmental problems per se. These problems are wicked problems in the academic sense of the word, and as a result, they will require interdisciplinary efforts for their resolution, i.e. the efforts not only of ecologists and environmentalists but of economists, members of the business community, and more generally of the L.Z. populace (and beyond) at large.