Vigilis-Bio: 100% Soil Biodegradable & Plastic Free Tree Shelters

It is no longer environmentally and socially acceptable for conventional tree shelters to be left in the environment after use as they will fragment and end up as long-lived “microplastics” in the soil. The collection of tree shelters after use is both difficult and expensive. We believe the way forward for Vigilis Tree Shelters and the forestry industry is to provide a tree shelter that can be left on site after use and then biodegrade in a timely and benign manner, without the presence of microplastics.

Vigilis-Bio tree shelters are made from a proprietary mixture of biomaterials (derivatives of potatoes, wood and corn). The cellulose structure of these materials is used to create a bio-based polymer. This combination has been chosen to provide the required functional performance (at least 5 years of tree protection) and end-of-life biodegradation behaviour, whilst minimising environmental impact during their manufacture.

Vigilis-Bio tree shelters are made from derivatives of potatoes, wood and corn. We source materials that would otherwise be waste products. The potatoes are scraps from the potatoes industry (damaged or misshaped). The corn is a specific type of corn that is not used for food production. The wood is sourced in paper mills – one of the waste products. So, yes, Vigilis-Bio Tree Shelters are sustainably sourced, contributing towards a circular economy.

Our prototype tree shelters have been subject to a desktop Life Cycle Analysis (LCA) by a 3rd party organisation (namely Bangor University BioComposites Centre). Based on initial analysis, Vigilis-Bio tree shelters have a 35% lower carbon foot print than shelters made from polypropylene (measured from raw material manufactured to end-of-life).

Yes, we have manufacturing operations running 24 hours a day, 6 days a week. We have been fulfilling global commercial orders for Vigilis-Bio for a few years. Before beginning commercial supply, we completed over four years of research. A project team of five developed and laboratory tested over 750 samples of the new products for mechanical properties, weathering and biodegradation over a simulated seven-year period at a cost of £500,000. We are running ongoing field trials with selected customers. These trials aim to validate at scale how the products perform in a variety of real-world sites and conditions.

We recommend that Vigilis-Bio tree shelters are kept in a protected location, such as a cool dark barn, if storage between planting seasons is required. This is because UV exposure will deteriorate the tree guards.

No, the installation process is the same for Vigilis-Bio biodegradable tree shelters and polypropylene tree shelters. Vigilis-Bio protects the tree in the exact same way as conventional plastic, but it will biodegrade at its end of useful life. We have developed our Vigilis-Bio Tree Shelters to have the same useful properties as traditional, recyclable tree shelters, including a twin-wall, flared rim and laser line.

Light transmission was an essential criterion in the design of Vigilis-Bio as this is important to the growth of young trees. There is no specific ISO standard to measure light transmission and literature suggests different views on the importance of various colours of light. However, when Vigilis-Bio is measured on white light (a combination of different colours), its transmission is 70% - 80% depending where measured. This is of comparable levels to the standard Vigilis product.

Yes. Our testing of the physical strength, flexibility and tear resistance are comparable with the existing recyclable Vigilis tree shelter products. Therefore, you can expect the same level of tree protection but without the need to collect the tree shelters at the end of their life.

Vigilis-Bio plastic-free tree shelters are designed to provide good physical protection to growing trees for approximately six years. After that time, the tree shelter will begin to break up. The tree shelters may last longer than this in some climates and weather conditions, however, we are only talking about a couple more years.

We manufacture both standard and biodegradable cable ties. Our biodegradable cable ties are made from the same bio-based blend of materials as our Vigilis-Bio tree shelters but with differing structural properties. We have been working hard to ensure the cable ties are releasable as well as biodegradable. These are available to purchase alongside our biodegradable tree shelters at an extra cost, if requested.

Our biodegradable tree shelters have been designed to “age” in the weather (from sun/rain etc) at a pre-determined rate that is optimised for the destinations climate. From the moment the tree shelters are installed, the sunlight and rain begin to break the bio-based polymer chains. Gradually the strength of the material is diminished. Following this deterioration, the tree shelter will break up from the impacts of weather and mechanical forces as the tree moves. This biodegradation process will take around 2-3 years and will begin approximately 5 years after tree shelter installation.

We have conducted testing on over 750 samples to understand how Vigilis-Bio tree shelters age in the presence of light and water. These tests have been carried out in laboratory chambers that are set up to mimic typical UK weather conditions. After approximately 5 years, the mechanical strength of the tree shelters is reduced to about 20% of the starting point and they break up under mechanical load. We are confident that between the 5 and 6 year period is the approximate timing when the tree shelter will begin to fragment.

Biodegradation is a natural process by which organic materials in the environment are converted to simpler compounds, mineralised and redistributed. In this context, biodegradation occurs by the action of microorganisms (bacteria and fungi present in the soil) that use complex material like grass and wood (and indeed Vigilis-Bio tree shelters) for the energy and material to grow themselves. Effectively these organisms can be considered to “feed” on the tree shelters, converting them partly into increased biomass for themselves and giving off waste excretions such as carbon dioxide.

The term “Compostable” is most often used to refer to specific testing that is carried out to determine whether products can be composted in carefully controlled “industrial” or “home” composting environments. Whilst the materials used in Vigilis-Bio have been tested in such environments and do compost, we don’t believe it is likely that this is how Vigilis-Bio shelters will end their lives, so we have settled on much more demanding “soil biodegradation” testing. Be aware of some 'bio' products on the market that are actually industrial compostable, rather than soil biodegradable, which means they will need collecting from site for industrial composting at 60 degrees.

Rigorous testing ensures that our tree shelters are biodegradable. ISO standard biodegradation testing measures the conversion by microorganisms of the carbon from the material into CO2 and biomass. This testing is carried out on fragmented Vigilis-Bio material put in contact with natural samples of soil containing microorganisms.

Biodegradation is a natural process and relies on warmth, moisture and microbes’ action found in leaf litter and soils. Whilst arid, wet and cold conditions can delay biodegradation, this is likely to happen in due course in most planting locations.

Our field-testing portfolio contains materials whose biodegradation has either already been tested to ISO 17556 (a method for determining the ultimate aerobic biodegradability of plastic materials in soils) or where such testing is being undertaken (in the expectation of a positive result). This testing method is different from composting (“home” covered by various national standards or “industrial” ISO 17088). However, it is similar to the real-life conditions where Vigilis-Bio shelters will be installed. Third-party opinion/results resulting from such testing can be provided to customers and other interested parties.