the recognition of hazardous trees

I can't really remember where I got this leaflet from. The date on it is 1988, so possibly I picked it up from a public library or post office in Devon or Dorset, where I grew up; certainly I think it's mine and always has been, it's not just another ephemeral scrap gathered from the Oxfam Bookshop where I volunteered, for years.

Although this is a useful leaflet I picked up from a public office of some kind, although its use to me at the time was questionable: I wasn't a landowner who needed to be told my responsibilities concerning trees. It would be years before I owned any kind of tree, let alone a dangerous one. But something about that sinister sketch of a hazardous tree lead me to hold onto the leaflet, with its dark talk of liability and risk assessment, and invocation of Shigometers and  Pressler Borers.

The central diagram breaks down the difficulties this hazardous tree is experiencing. Weak forks, basal cavities (particularly dangerous if present between more than one pair of buttresses) and target cankers. Who knew that trees concealed such darkness, such danger? The tree itself is some odd composite with Oakish bark, Ashish habit, Beechish leaves and an improbable pollard point at more than twice human height. It radiates the commonsense hostility of a technical diagram, while having all the chummy familiarity of a Ladybird picture book. It hints at drastic solutions, but the section on how To render a dangerous tree safe is tantalisingly brief.

Hazardous trees are a massive concern at the moment of course. You'll have heard about the Sheffield Tree Massacre. The methodology applied to modern trees is a little different; originally the 5Ds, now expanded into full 6D. Is the tree:

• Dead
• Dying
• Diseased
• Dangerous
• Damaging
• Discriminatory 

If so, it's hazardous, and is taken down. But here's a glance back to simpler days:

 The Recognition of Hazardous Trees - The Forestry Commission.