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Tree Constraints Plan - A Means to Help Development of a Site The tree constraints plan is a means that is used to support any development plan that attempts to widen the space while taking into consideration many hurdles and constraints caused by the trees. Tree constraints may include shading, space for future root and crown development and routing for overhead and underground services. The early availability of a Tree Constraints Plan prepared by environmental consultant to the development design team will be of immense help for the developers. It will help reduce redesign time for the developers because trees will be identified before the initial design is drawn. It will also reduce the risk of applications not being registered by Development Control. Timely Tree constraints plan also reduce the risk of tree issues getting into the way of development during the planing application process. It also increases the speed at which tree issues can be dealt with during the application process. All these factors need to be taken into account by professional environmental engineering services. The Tree Constraints Plan should be a combination of the information gathered during a topographical survey and an accurate tree survey. The topographical survey includes location of all trees, shrubs and hedges and other relevant features such as streams, buildings and spot level heights. The tree survey should be carried out in accordance with BS 5837 (2005) and contain some important information about each tree on the site that has a stem diameter above 75mm measured at 1.5m above ground level, and those trees of smaller diameter that are of particular interest or potential value. This important information include: Tree species, height, stem diameter taken at 1.5m from ground level (Diameter at Breast Height), branch spread (in four directions North, East, South and West, height of crown clearance above ground, age class, physiological condition, structural condition, preliminary management requirements, estimated safe useful life expectancy and category grading. This information should relate to tree constraints plan. Hence, it is good if this is carried out by environmental engineering services under the guidance of experienced environmental consultant. When the construction of the site starts, utmost care should be taken of the trees. Not only the roots of the tree and its soil surface, but also its other parts above the ground like its trunk, branches, leaves are important. If there is a problem in the root, it is likely that the entire tree may get affected and eventually it may lead to total collapse. Tree roots can be easily damaged by: 1. Severing and removal of roots by excavation 2. Crushing of roots by vehicles/plant or storage of building materials or soil 3. Soil gets filled with deposits leading to compaction of the surrounding soil and that leads to death of the root by asphyxiation (lack of oxygen) or drought. 4. Severing and removal of roots by excavation 5. Roots can also be dead as the soil levels get changed around the trees and that leads to asphyxiation and exposure 6. Poisoning from spillage or storage of fuel, oil, chemicals etc. 7. Tree Constraints Pan can also be helpful if it recognizes that surfaces is so impermeable due to such installations, and therefore, tree health can deteriorate considerably. It is vital therefore that the Tree Constraints Plan should also clearly show the Root Protection Area of each tree. A tree’s Root Protection Area can be equated to a circle, using the tree as the center-point, with a radius that is twelve times the tree’s Diameter at Height for a single stemmed tree or alternatively ten times its basal diameter measured above the root flare for a multi-stemmed tree.

Tree Constraints Plan - A Means to Help Development of a Site