Trees and Development
You see it every day—trees abused by construction, declining slowly, painfully, inevitably. It’s hard to watch, but there is a tool that can save trees from construction impacts, and anyone can use it. After publishing The Evaluation of Hazard Trees in Urban Areas, the International Society of Arboriculture commissioned Nelda Matheny and James Clark to write Trees and Development: A Technical Guide to Preservation of Trees During Land Development.
We’ve all heard the arguments for NOT preserving trees near construction, so in their Introduction the authors provide reasoned responses to make when you hear the following:
“Too Costly!” It’s a trade-off, with costs typically recovered by faster sales, higher prices, and enduring value.
“Over-regulation!” We all have a right to life, and the clean air and water provided by trees are a prerequisite for life. Courts uphold reasonable environmental standards. Where staff is trained to fairly enforce them, needed flexibility can be allowed.
“It’s just a tactic to stop us from building!” If a community holds tree preservation as an important goal and clearly defines its expectations to developers, then tree preservation simply becomes another aspect to project planning. Once a project (and its tree preservation plan) is approved, both development team and public agency staff must act in an honest, cooperative manner.
“We can’t control our subcontractors.” If following a tree preservation program is made a part of a subcontractor’s contract (with penalties for noncompliance), then adherence will follow. For best results, developers should educate subcontractors prior to the start of work.
“It’ll makes our whole community too expensive to develop!” To be practical, projects with mature trees sell quicker at a higher price, and remain more attractive to buyers.
“We don’t know how to preserve trees.” It requires commitment and the application of specialized knowledge, just like engineering and architecture. It is for this reason that a consulting arborist should be a part of the development team.
The next complaint often heard is, “We already pay a landscape designer”. Most landscape architects get no training in tree preservation. At NCSU in particular, how to handle existing trees is not part of the curriculum. LA’s typically have too many other responsibilities to also take on tree preservation.
The rest of the Guide lays out the entire process of preservation in a reader-friendly fashion. It first reviews tree biology and the means and methods of development, then simply, step-by-step, walks the reader through the process of successfully preserving trees. Two tips stand out as especially useful:
“Brush shall be chipped and placed in the tree protection zone to a depth of six inches”
This cheap and easy step can save more trees than any other. Even outside the protection fence, a thick layer of mulch prevents compaction better than any other method. Whether turf or shrubs are going in later, they will be easier to install and need less replacement if the soil is protected. It also retains “an ecologically functional land base capable of growing trees well into the future”.
“Adjust finish grades so that the pavement section is built on top of the natural grade, using a ‘no-dig’ design.” Since roads and sidewalks are safer when water runs off faster, this tip makes sense both for tree survival and safe travel. Use of geotextile fabrics to reduce compaction and prevent the subbase from mixing into the soil also preserves trees.
Tree preservation is a job that everybody wants done, but too often it fails for lack of information. This Guide, available from the ISA,
[email protected], is the best tool for getting the job done, and keeping the canopy over our communities. Coming soon are the new ANSI Standards and ISA Best Management Practices on Preservation, which will give you even more support in your fight to protect trees from bulldozer blight!
