Coronet cuts or Fracture pruning is a pruning technique that mimics the way natural
tears and fractured branches occur on stem wood and branches.
These characteristics can be caused by static limb failure- an overladen branch/stem,
decay or rot in the structure, poor adaptive growth from a union or from storm damage
such as strong winds, snow or heavy rainfall.
How will this technique benefit the tree?
When limb failure occurs naturally, these new features create a micro habitat for
microorganisms and successive species- wood louse, earwigs, etc. These in turn,
support birds and bats’ and other organisms with food and shelter
Coronet cuts are designed to promote decay and therefore benefit microorganisms that
live off the decaying wood. Whilst good for the local ecology, generally, this isn’t good
for the tree. It prevents the branch sealing the wound and preventing pathogens from
entering.
When should the use of coronet cuts be employed?
Here at DR STUMP, we tend to only employ fracture pruning on trees earmarked for
monolith, veteranisation or severe decline.
This allows colonisation of the tree by the local fauna to encourage improved
biodiversity of the area – a feeding ground and bat/bird hotel.
When retaining a declining tree for habitat, there are several risk factors to understand
and mitigate, the most prominent being public safety. For instance, if the tree is over a
road/ bus stop, play area or near a dwelling, we may look to remove the tree for safety
reasons. However, in parkland with low footfall, woodland or reserve, where risks to
public health are much lower, this technique is a valuable tool in creating habitat for the
wildlife.
