The health and productivity of woodland in the eastern region will be under threat from grey squirrels if the use of Warfarin-based baits is banned by the European Union (EU), landowners have warned.

The Country Land and Business Association (CLA) says Warfarin-based bait is the most effective method of control for grey squirrels.

But the European Commission is currently carrying out a review of Warfarin and its use in squirrel control and it fears this could result in limits being applied to usage.

The UK is the only EU member state where Warfarin is extensively used, and the CLA say it is an important issue to be raised with the Commission and other member states to ensure landowners can continue to cost-effectively manage grey squirrels in their woodlands.

The Association says any attempt to control grey squirrels is almost impossible without Warfarin, and failure to control the species on top of the spread of several new serious tree diseases – notably Ash Dieback and Acute Oak Decline – will hinder any young woodland’s chances of surviving until maturity.

Grey squirrels damage trees by gnawing at the stem to get to the sap beneath the bark. If the squirrel gnaws all the way round, the tree is likely to die. All broadleaved species of tree can be attacked by squirrels, with oak, sycamore, beech and sweet chestnut particularly vulnerable.

Chairman of the CLA’s Suffolk branch and its forestry and woodlands committee Graham Downing, said: “Grey squirrels cause big problems and a lot of damage to timber trees by stripping bark. This activity can cause diseases and fungal growth in the tree, affecting quality. This is an issue where people are growing high quality timber for wood production – they need straight, tall, disease-free trees for the saw mill. If the grey squirrel population increases, then the chance of high-quality, high-value timber decreases.”

The damage caused by grey squirrels does not just affect those growing timber for profit, but also people managing woodland as a source of fuel for biomass heating and amenity, the CLA pointed out.

CLA forest and woodlands adviser Mike Seville said: “Grey squirrels have already been responsible for the demise of the red squirrel throughout most of England. They have always been a pest as far as foresters are concerned because the damage they cause means it’s difficult to grow trees of any quality. The other thing they do is make it really difficult to grow any quantity of timber. Buying some hoppers and putting some Warfarin out is the cheapest and most effective way to deal with them, given the size of the problem. Even if you’re not growing high-quality timber, you need to effectively manage squirrels if you want a plentiful fuel supply.”