Tree guards - why use them and reducing the environmental impact

Before I started to plan to plant a woodland I always thought that tree guards were used to protect saplings from deer. I now know they are used to prevent small mammals from eating the bark and killing the sapling particularly hares, rabbits and voles. Deer would of course nibble the shoots coming out of the top anyway.

The damson tree above had only been planted a couple of days when it was nibbled. It has survived happily and the deer fence has since been tightened up in places so there are fewer coming and going now.

This is a good reminder of what a red deer can do - the efficiency of the way she clears the bluebells is something to behold!

The deer fence was erected a year ago (September 2022) and this year there has been some natural regeneration of trees where the previous two years there hasn’t which is a good start. That will not be enough protection when over 4,000 saplings go into the ground and they will need specific protection from smaller mammals as well.

The recommendation from the Forestry Commission is to use tree guards in specific circumstances which are present at Bel’s Wood. https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/896121/Tree_shelters_guide.pdf

This includes the presence of mammals such as rabbits and hares and when planting over 3 hectares of land. 

Voles are a particular problem for young trees but I have not knowingly seen any at the wood although I have picked up many mice mostly at night and I do not think I would be able to tell the difference from the black and white shots of a small mammal jumping around

There are hares at Bel's Wood too but I have not been able to capture them on camera sadly but I have seen a pair frolicking in spring.

There is technical advice given on this website which sells ‘Rainbow Treebio Biodegradable Spiral Guards’ https://www.green-tech.co.uk/tree-planting-products/treebio-biodegradable-tree-planting-products/treebio-biodegradable-spiral-guard

'The main function of the spiral tree guard is to protect young trees from destruction by  animals. The following table shows the required size for maximum protection from specific animals.' 

Animal	Length of Spiral
Rodent	45cm
Rabbit	60cm
Hare	75cm
Sheep/Deer	100cm - 150cm

 

Initially plastic guards were used to protect trees. These have been a cause of pollution over the years especially when they have not been removed from the grown trees or disposed of correctly. The Woodland Trust has done research into this issue and promotes the use of biodegradable tree guards https://www.woodlandtrust.org.uk/about-us/what-we-do/research-and-evidence/plastic-tree-guards/. The early degradable guards were made from plastic and of course these released micro-plastics into the environment. Non plastic biodegradable tree guards have now been successfully developed.  Initially cardboard was used but these have not lasted long enough to give protection. Trees need at least 5 years to ‘get away’ and in poor quality land maybe longer. Different materials have been tried which last long enough and biodegrade into compostable material and this is what I shall be using.

• The CT Bio Spiral guard has a UV stabiliser incorporated at the time of manufacturing to provide a stable service life of 4-5 years.
• 100% plant based - no plastic!
• Tested to meet conformity to EU guidelines
• Environmentally friendly and sustainable.

If the Bio Spirals are left in the environment they will degrade over time due to the bacteria found in soil or due to enzymatic reactions. Alternatively, they can be inserted into an industrial composting unit which will degrade them within 6 months."

There is an argument to plant without tree guards. Research quoted in this article in the Guardian says that 85% of trees survive with a tree guard while 50% survive without. https://www.theguardian.com/environment/2021/aug/24/trees-should-be-planted-without-plastic-guards-says-uk-study-aoe. The proposition is to accept the higher rate of failure and know that more trees need to be planted as replacements rather than add the environmental cost of manufacturing new tree guards. Having accepted funding through the woodland creation grant  (EWCO), I am following the Forestry Commission advice to use tree guards and aiming to do this in way that minimises the environmental impact.

I shall be re-using 1,500 plastic tree guards. I have neighbours who bought a woodland that was planted 17 years ago. Due to personal circumstances, the owner at the time was not able to remove the guards from the trees and they have stood there ever since. The new owners are removing them from the well established trees and they are retrieving those where the trees did not thrive. They tried to find a way of recycling them but the material the guards were made from cannot be recycled. The owners were beginning to take them to the council’s recycle centre to be disposed of with household waste when they showed me around their wood earlier this year and explained the problem. I could see that, while some were bent and cracked, others still had spring in them and looked like they would work for some more years.

The wood they have been used in is in is healthy and thriving. Also it is in the same water catchment area as my wood and about 3miles away as the crow flies. I feel that the risk of cross contamination of any pathogens from their land to my land is not a concern as it is basically on the same hillside.

The guards are however not nice to handle. There is soil and moss on them and inside them; some still have small stakes inside them and there is an occasional frog happily making the guard their home. I have transported car loads to my wood 

I have left them at Bel's Wood in the rain hoping that that may clean them. 

It has occurred to me that the contractors who will be planting the trees will need to move them to each of the planting zones and will not have time to sort them. I have therefore developed a method of washing the guards in the beck to remove the moss and soil caught inside. This gives me a chance to check the quality of each guard. I am only keeping the ones which have spring in them and will therefore effectively exclude small mammals. Large gaps where the guard has stretched having been wrapped around a larger tree, may not work. 

    

I did have to pause the effort when Cumbria received a month's worth of rain in 48hours - I feared that the tree guards would float down the Gilpin into Morcambe Bay if I threw them in for a clean!

Finally I have put them into bundles of 25 held together with jute cord (I didn't want to use plastic ties creating another permanent material) and tied a knot that can be used to carry them around the site. I have left them upright as best I can (a bit like wheat sheafs) so that rain can continue to wash the insides as well as the outside.

          

The ones that are not good enough to use, I am placing in my  household bin. This represents a small minority of the total pile of guards collected. 

So far I have inspected, cleaned and bundled 1.025 guards with help from friends.

I have committed to preparing 1,500 by the time the trees are planted in November. I may be able to prepare more guards after this and hold them in reserve should any that I have used fail. The land where they came from planted about 8,000 trees and I have probably processed about 1,200 so far.

If I have time I can continue cleaning them up and see if anyone else in the area would use them. Although I would prefer to use non plastic biodegradable guards, re-using these non recyclable plastic guards is the right thing to do as it reduces the need for new guards to be manufactured which is the most powerful of the 3 environmental requirements of reduce, re-use, recycle. They will be put into the waste bin at the end of their useful life and used for energy production from waste material at that point so will have hit all three of the requirements.I hope that this proves to be a good decision for the wood in the long term.