With over 150,000 visitors expected this season it is paramount that the property is a safe environment to visit. Whilst this is not so much a problem in the garden itself, the surrounding estate can have potential hazards and if there is one thing we have a lot of on the estate it is trees and it is the trees that can hide possible risks.
During the exceptionally wet winter we all experienced, we also had the problem of occasionally very high winds. Wet ground and high winds mean the potential for windblown trees is increased dramatically. Why is this? Well, the saturated ground on which the tree stands undermines what would normally be a solid base and allows much more movement of the tree’s roots. On hard ground the roots are “locked” into place keeping the base of the tree solid. Then add in high winds and you have the scenario of wind knocking over trees that would not normally be affected if they are growing on dry ground. Here at Sissinghurst we have probably lost 200 trees as a consequence of wet ground and high winds. In dense areas of woodland the problem is magnified as a domino effect of one tree knocking down others is a regular occurrence.
We obviously have a legal and moral obligation to ensure any visit to the estate is as free as it can possibly be from any potential hazards. To meet this obligation we conduct yearly tree inspections (though we do check more regularly after storms and bad weather). During these inspections we are looking to identify trees that represent a significant risk, either now or in the future, to people or property and deal with them accordingly. Some parts of the estate are more accessible to visitors than others and so we use zoning as a way of prioritising any tree work required. A high zone would be an area any of our trees overhang public roads, paths with extensive usage or the car park at the property. A medium zone would be some of the paths that run through the estate that although used do not affect the same number of people a high zone would. Finally a low zone would be an area the public do not have access to such as trees on the edge of fields that are well away from any paths or roads.
Once we have identified a problem with a tree we have to ask ourselves certain questions;
a) What is the likelihood of the problem occurring?
b) What is the likely consequence of its occurrence?
c) Is it reasonable to protect against it?
We will then prioritise any work needed with the highest priority going to work required in a high zone. The majority of tree work is completed by Sissinghurst’s Ranger department but there are times when we will have to call in contractors to do the work for us. This might be a case of work required on a tree overhanging a main road. The contractor will have more appropriate equipment and be able to liaise with the local authorities should road closure or traffic lights be required.
All our tree inspections are logged and updated as and when work is done to trees identified as potentially hazardous. It is vitally important that we keep up to date records of our inspections as should any incident occur then the authorities can inspect out records to see we have not failed in our duty of care.
We take our tree management very seriously here at Sissinghurst as the estate has to be many different things to many different people. We need the estate to be working for us, to produce timber for our fencing and stock to sell at the shop amongst other things. The visitors who use the estate paths expect attractive wood lined walks they can walk the dog or perhaps spot wildlife. But the one thing we all expect is it to be a safe and pleasant environment and with good management and regular checks we hope this is exactly what we have.