The following notes are intended for used by designers, or by design & build landscapers when surveying projects, especially in the domestic sector, to help ensure that every angle is covered, nothing relevant is missed, and provide you with the most efficient methodology when conducting such surveys.
The second in the series concerns trees, and is presented in the form of a template, purely as a guide when surveying. There will be instances that information will need to be added to this checklist, such is the nature of preparing for a garden design.
Site overview – trees on site
Name of customer
Address of the property, including post code
Contact telephone number (in case of delays)
Email address
Date of original first contact.
Date of this visit
Tools and accessories
Note book and pens
Tree identification book/s
Mobile telephone/camera
Spare batteries for any electrical equipment
Tape measure (for girth assessments at 1m above soil level)
Pre-visit information as may be available
Google Earth images, both current and historical, (for referencing any changes over the years, especially tree cover, and additional housing in the immediate vicinity that may affect drainage and water run-off in/out of the site)
Status of the site (National Park, Listed Building, new build, value when last sold, date when the property last changed hands)
Any tree preservation orders that may be in place. (Check with the local council)
Surveying
Check and identity all trees in the garden with a diameter greater than 30cm, or taller than 3.0m
Check and identify all trees overhanging the boundaries of the site
Assess -if necessary, and identify all trees that are within ten metres of the boundary, especially large trees such as oak and ash.
Create an approximate plan of the site (if possible) and annotate each specimen identified, including those of uncertain species, including placing them in sequence on the plan.
There are several reasons for making these specie surveys, as many will cause practical problems with sticky substances covering anything underneath their branches, caused by aphid excrement known as honeydew. These species include Tilia euchlora, Acer platanoides, Quercus in variety, Betula pendula and Pinus in variety.
Their location may decide the siting of seating areas, and car parking places.
Other problems caused by trees or large plants may be difficult to eradicate stains, such as tannins (Quercus) and Wisteria (any damaged wood will leach sap stains especially problematic on paving and furniture)
Be aware also, that certain types of trees will harbour unwelcome ‘guests’ including oak red spider mite, which will make any vegetable garden or top fruit orchards susceptible to damage when designed under or near to these specimens.
Tree roots
Carefully survey any existing areas of driveway or paving for signs of movement or ‘ground heave’ in the vicinity of any trees, including those on the other side of the boundary.
Check for any suckers, especially those from species such as Fraxinus excelsior and Acer platanoides, as these grow near to the surface, and callous over when damaged or restricted by pavements, including tarmac and resin (even though they are permeable)
By providing your client with researched and evidence-based proposals, showing clearly how you arrived at your design decisions, taking into account all site factors, you will not run the risk of being held liable for any claims for negligence in the future.
For further reading, see Tree Roots and Buildings, by DF Cutler and IBK Richardson (1989) published by Longman Scientific and Technical.
Also, Tree Roots and Their Effect of Paving/Driveways in The Landscape Library www.landscapelibrary.co.uk
Trees, both existing and planned, form the major backbone of a garden design, and great care should be given to future generations when nominating varieties and species. All too often, the wrong tree planted in the wrong place can cause disruption above and below ground after a few years.
Think beyond the obvious biomass, and consider the other factors such as those listed above when drawing up designs. Tree are not only about shade and colour. Trees are for life!
IF IN ANY DOUBT, ASK THE CUSTOMER TO CONTACT THE LOCAL TREE OFFICER FOR ADVICE.