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How to practise biosecurity in woodlands: Keep it Clean

Biosecurity in forests and woodlands

Biosecurity is a way of working that reduces the risk of harm to our forests and woodlands both from invasive or non-native species, and from pests and diseases.

Pests could be certain insects, diseases include bacteria, fungi and viruses.

Invasive non-native species include rhododendron, American skunk cabbage, Japanese knotweed and Himalayan balsam.

Why biosecurity is important

The threat to our forests and woodlands has never been greater. Trees and plants in Britain are now vulnerable to a range of new pests and diseases as a result of the increased movement of goods around the world and climate change.

Climate change may alter the area over which conditions are suitable for particular pests and diseases. For example, the pine processionary moth (Thaumetopoea pityocampa), a Mediterranean species, is thought to be moving northwards with climate change.

Extreme weather events may potentially change the behaviour of native and introduced pests and diseases in unpredictable ways and climatic stresses such as drought may leave trees more vulnerable to attack.

Outbreaks can result in economic losses for the forestry industry and for related industries, such as tourism.

Everyone who works or visits the countryside can make a difference. If you are routinely going from woodland to woodland, then it even more important that you practice good bio-security.

Woodland visitors

Clean your equipment and animals

Pests and diseases can easily catch a ride in the mud on your boots or wheels of your bike. Visiting with clean kit will slow down any spread of tree pests and diseases as well as keeping our forests healthier for longer.

The best time to clean bike tyres or shoes is before you leave the woodland, but you should make sure your kit is clean before you head off for your next visit to the countryside. You don't need special equipment, just a stiff brush like a washing up brush and a little water.

It takes a matter of minutes to brush off your boots, wipe your dog's paws or wash your bike before you next head out. Make it part of your routine and it will soon become habit.

Not all visitor centres or car parks have washing facilities as the emphasis is arriving in the countryside with clean equipment, whether it be clean shoes, clean bikes or clean pets.

The spores from some tree diseases can live for a very long time, sometimes years. Even if you haven’t been in the countryside for some months, it’s always best to check your kit is clean before you head out.


Visiting infected areas

You should continue to follow the practice of visiting with clean footwear and equipment. Follow any advisory signs as these will contain the best advice for the particular pest or disease.

Plants, seeds and fruit from outside the UK

Plants, seeds, fruit, flowers or vegetables you find overseas should not be brought back to the UK as they can carry pests and diseases that would destroy UK plants, trees and crops.

Woodland owners and managers

Biosecurity is important when working in any forest or woodland, or when entering any land or premises where there is a risk of spreading tree pests and diseases (for example, where timber is stored or processed).

It is not always possible to see pests and diseases. Pests are most often transported in soil or organic material, like plant debris, that can be carried on footwear or by the wheels of vehicles and forest machinery. They can be transmitted accidentally by people moving between different forests and woodlands. Diseases may also be spread via the equipment used for tree work.

Some pathogens are dispersed in water and so the risk of these being spread increases when conditions are wet.

Check site restrictions

Before you visit a site, check if there are any existing site restrictions. If so, seek advice from the lead authority before visiting the site.

If you're carrying out low-risk activities

Low-risk activities include routine operations that are unlikely to involve contact with high-risk pests and diseases. Examples include the day-to-day forest and woodland management, monitoring, routine visits to sites or premises (including tree nurseries, sawmills and timber processors), and routine inspections of ports and dockyards to check compliance with Plant Health Notices.

If you suspect that there is no damaging tree pest or disease present on the site, carry out low-risk biosecurity measures.

If you suspect that there is a damaging tree pest or disease present on the site, think about the risks of transmitting the pest or disease to a new site. If there is a low risk, carry out low biosecurity measures; if there is a high risk, carry out high biosecurity measures.

If you're carrying out high risk activities

High-risk activities include specialist or targeted operations that may involve contact with infected or infested material. This could be a visit to a site or premises as part of a pest surveillance programme or to collect pest and disease samples, inspections of a sawmill processing infected material, or to a port or dockyard importing potentially infected material.

For high risk activities, you should always carry out high risk biosecurity measures.

Low risk biosecurity measures

  • Wear footwear and outerwear that can easily be kept clean
  • Clean footwear and outerwear regularly. Ensure they are visually free from soil and organic debris
  • Clean vehicles such as vans, timber lorries and forestry machinery regularly. Do not let mud and organic debris accumulate on tyres, wheels or under wheel arches
  • Restrict the equipment taken onto a site – take only what you need for the task
  • Ensure all tools and equipment are clean, serviceable and free from organic debris

High risk biosecurity measures

  • Plan to visit highest-risk sites last
  • Clean footwear and outerwear between site visits by removing leaves, soil and other organic material
  • Spray clean footwear and outerwear with disinfectant until it runs off (boots can be dipped in disinfectant)
  • Avoid vehicular access to high-risk sites – park off-site if possible
  • Keep to established hard tracks
  • Remove mud and organic debris from tyres, wheels and wheel arches
  • Clean and disinfect tyres and wheels
  • When taking samples, clean and disinfect cutting tools after each sample
  • Clean and disinfect other tools and equipment before leaving the site
  • Keep any samples in sealed containers

Keep a personal biosecurity kit

You should carry the following items if cleaning and disinfection are required:

  • Plastic storage box
  • Supply of clean water (5 litres)
  • Boot tray or bucket
  • Hard brush and boot-tread scraper
  • Disinfectant
  • Vapour-proof container for disinfectant
  • Protective gloves
  • Eye protection
  • Brush, sponge or portable sprayer
  • Paper towels/wipes
  • Re-sealable bags (for samples)
  • Plastic bags and ties (for clothing/PPE)

Portable pressure washers designed to clean bikes are also a good addition to a biosecurity kit. They work by being plugged into cigarette lighters in cars and can be easily used out in the woods.

Using disinfectants

Alcohol-based disinfectant (such as industrial methylated spirit or isopropyl) at 70% concentration is recommended as it is effective against Phytophthora and other pathogens.

You must be aware of the relevant health and safety guidance and follow the COSHH risk assessment for the product you use.

In addition to this you should always:

  • Follow the instructions on the product label
  • Wear protective gloves and eye protection
  • Mix and use disinfectant in a well-ventilated place
  • Carry out the disinfection process on a flat area well away from any watercourses
  • Apply disinfectants to clean surfaces – remove mud, soil, leaves and other organic debris by first washing with water (or hosing down if necessary and where permitted)
  • Observe any specific contact times and, if necessary, rinse off the disinfectant afterwards with clean water

Minimise pollution risk from run-off. Do not allow disinfectants or washings to enter watercourses, surface-water drains, or springs and wells.

Identify and report pests and diseases

Read more about how to identify and report pests and diseases.

Resources for woodland managers

Download posters and resources for woodland owners and site managers.

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