Is The Anything Down There?
by Phil Wade

Fujikura Europe Ltd introduce the TreeRadar Unit (TRU) to identify and locate tree roots

Ground Penetrating Radar (GPR) technology has been used worldwide for several decades to locate objects underground – including pipes, ducts, archaeological remains etc. When a radar wave emitted from a surface antenna encounters a boundary between objects with different electromagnetic properties it will reflect, refract and/or diffract from the boundary interface in a predictable manner.

It is only relatively recently that Professor Tony Mucciardi – a world renowned expert on GPR – finished developing the TreeRadar Unit (TRU) that was not only able to detect and locate decay in tree stems but, perhaps more importantly, detect and locate tree roots reliably and affordably, utilising the patented TreeWin analysis software.

Tony visited the UK from his native Maryland, US home last year at the invitation of Fujikura Europe Limited (FEL), recognised leaders in the supply of hi-tech equipment to the arboricultural profession. FEL liked what they saw and have since become the master distributor of the TRU in the UK, Europe and other selected overseas territories.

Picture shows the TRU in the foreground and the cedar tree. Line scan number 1 was done on the pavement shown. Dr Jon Heuch is standing nearest to the TRU.

There are a number of hi-tech devices available for decay detection in tree stems/limbs but the TRU is the only device that allows tree roots to be accurately mapped, thus providing vital and necessary information in situations relating to development sites, subsidence claims etc. In the past the lack of actual scientific information in such instances has led to some bitter disputes between opposing parties with different opinions. The TRU can now be used to provide the scientific evidence required by experts to back up their conclusions.

Taking subsidence as just one tree related phenomenon, it is expected that there will be a record number of claims in 2006 because of water shortages. According to the Association of British Insurers (ABI), the typical annual cost of subsidence approaches £400 million per annum with 70% of cases being tree related. It is also predicted that these costs will DOUBLE by 2050! This seems to be an awful lot of money hanging on an opinion not based on scientific fact.

One case study recently involving the TRU was in Ashford, Kent. A beautiful 100 year old Atlas cedar tree situated close to a children’s nursery had suffered accidental root damage during building of an adjacent nursing home.

Although the root damage was accepted as accidental the question remained as to whether the tree now posed a significant risk to its surrounding environment – particularly the nursery. In fact, the tree was due to be felled on the basis of perceived risk.

It is worth mentioning here that had the TRU been available prior to the building work then root damage could possibly have been minimised or prevented altogether.

A leading Consultant, Dr Jon Heuch, was called in to investigate the tree root system. Jon was the first to purchase the TRU in the UK because he fervently believed that this ‘torch into the ground’ was the
way forward in instances exactly like this – a much loved and admired tree that was threatened with the axe because of root damage.

Several ‘line scans’ were carried out next to the cedar tree and an actual radargram is shown with the detected tree roots depicted as yellow dots. These are ‘virtual’ trenches – just imagine you are stood in a trench and the yellow dots are the tree roots emerging from the tree into the trench. Hence the number, depth and location of tree roots can be determined. Roots as small as 10mm diameter can be detected and the TRU can be used on soil or through concrete, asphalt, paving etc. Further work is currently being undertaken to colour code roots according to diameter range and it is also envisaged that it will be possible to identify decayed roots in future.

Using the TRU information and following ongoing further investigations, Dr Heuch will now be able to better deduce – based on facts rather than purely on opinion - whether this tree actually needs to be felled.

Scan 1

Scan 2

Scan 3

Cedar Tree Raw Data (above) This shows 3 radar line scans: number 1 was done on the asphalt pavement and 2 and 3 on the grass where the tree is located.

The grey/white radargram is overlaid with yellow dots which show tree root positions.