Our native trees have never faced a more formidable array of threats from disease and pests
Addressing the threats to our native trees involves bio-security, research and land manager engagement, writes Lord Kinnoull.
We are the stewards of our Islands’ environment and are so rightly so very proud of “Our Green and Pleasant Land”. But that environment is fragile.
Every generation faces challenges that it must overcome to protect that environment. The very essence of that environment and the diversity of flora and fauna it supports is our native trees.
Without the Oak, Nelson would have had no ship, without ash, the bowmen of Agincourt no arrow shafts. Beech gave the stocks for the muskets at Waterloo, while birch plywood made wings for the Wooden Wonder, the Mosquito aeroplane.
Our native trees have never faced a more formidable pall of threat from disease and from pests.
There are many diseases. I want to reflect on just two situations
Ash dieback disease was first identified in Europe in Poland in 1992. It kills trees, especially young ones. Thereafter it spread and was first reported in the UK in 2012. We imported the problem from continental European nurseries. Bio-security measures for this disease have been in place since 2012 but the damage had been done. A brutal lesson in the 1st necessity of bio-security.
Various research efforts are underway and I note it was British scientists that published the genetic sequencing of ash in December 2016 with observations about resistance to the disease. The sums required for such research are small compared to the aggregate totals that we rightly spend on our environment. It is most important that we spend adequately on this 2nd necessity.
The absolute necessities of good bio-security and good research are evident in the most distressing tree disease situation, that of our native oaks. Oak is faced with a plethora of deadly diseases and pests. There are at least 4 killer diseases attacking our oaks. Action Oak is the coming together of the 37 big interested parties to coordinate effort on this problem. The need for research is manifest.
The oak battle is one both of disease and of pests. These are interconnected as the pests can be vectors of diseases both as direct carriers and as weakeners of trees.
The worst and most destructive of all the pests is the grey squirrel. Grey squirrels were first introduced in 1876. Between 1876 and 1930 an aggregate of around 500 animals are recorded as having been released into the wild.
Those 500 introduced up to 1930 have grown into a grey squirrel population 90 years later estimated at 2.5 million.
And the problem where broadleaf trees are concerned is that the grey squirrel ring barks younger trees to get at the sap. This causes terrible wounds to the trees, killing sometimes 70% and making the timber quality of the remainder poor.
It is no wonder that grey squirrels alone as a threat are responsible for a dearth of new broadleaf commercial planting in the south east of England.
In view of its position as the leading threat to trees the problem of what to do has spawned the UK Squirrel Accord with its 37 big interested parties. It has commissioned fertility control research where it is hoped that a suitable active substance and hopper delivery method can be perfected to allow simple fertility control to shrink grey squirrel numbers significantly allowing forestry a chance.
The list of pests is long. Deer remain a problem, well managed by some landowners and not at all by others. This shows up a 3rd necessity, that of the cooperation of all land managers particularly where pests are concerned.
Addressing the threats to our native trees involves really good bio-security, really good research and really good land manager engagement. We, as stewards, are obligated to act.
Lord Kinnoull is a Crossbench member of the House of Lords.