Reduce the effects of winter and salt with outdoor FM preventative measures
The most intensive outdoor FM maintenance jobs might take place before the winter, but it is a year-round activity. Now we are mid-winter and many of us have experienced snow, heavy rains and winds, how should we minimise the impact of this adverse weather on our grounds, roads and pathways?
Winter grounds maintenance
Trees and branches should already have been trimmed back before the winter months but check if any low-hanging tree branches near rooves and footpaths have been missed, which might become a hazard with heavy snow. To prevent snow damage branched evergreens and boxwoods should have been tied up loosely. When removing snow do not use a broom or snow shovel to knock the snow off shrubs, as the limbs may be frozen and extremely fragile. Most shrubs and hedges can be pruned during the winter months, as well as evergreen and deciduous trees, but avoid pruning in heavy frost or sub-zero temperatures as this can cause dam- age to the plants’ internal structure.
Walking on frozen lawns causes bare spots that will not re-grow until the grass comes out of winter dormancy. When temperatures drop and when it is not too damp under foot grounds operatives need to be flexible when scheduling leaf clearing and litter picking.
Some might be tempted to reduce winter activity altogether, but It is important to keep on top of this. Leaves and debris that sit on the surface of the lawn prevent sunlight from reaching the grass underneath and they attract worms and bacteria up to the surface. This can lead to more moss content and stunted growth and dead or brown patches which, in the long run, can cost more to put right. Debris can also be blown around and collect in areas that could cause additional problems such as poor drainage or slippery surfaces.
Salt spreading and vegetation
Just as salt in moderation is fine the humans, the same is true for vegetation. Most de-icers are technically salts and Sodium Chloride is not classified as dangerous to the environment. However too much salt can damage plants in a couple of ways:
- Direct contact from high concentrations of salt spray from roadways and repeated shovelling or blowing snow that contains de-icers onto nearby landscape plants. In dryer periods when rain can’t naturally clean the vegetation more salt will be absorbed through repeated applications. Depending on a plant’s and shrub’s tolerance, this contact can cause bud death and twig dieback and on evergreens, needle flecking or browning.
- Repeated yearly applications can result in a build-up in adjacent soil which may damage plant roots so they are unable to take up water. Plants’ symptoms include wilting (even when soils are moist), marginal leaf burn or needle-tip burn, and general stunting.
Some actions can be taken after the event by watering well-drained soils to leach some of the excess salts out. But this will not work with fine-textured clay soils or soils with inadequate drainage. It is better to take preventative action to minimise the effects of salt.
The moral is responsible use of salt
Right time - use a gritting and snow clearance service that is proactive as salt is more effective and less is needed when spread before ice forms when water freezes at zero degrees. Professional services are triggered by accurate local forecasts of road surface temperatures and a knowledge of local site conditions. The effectiveness of salt is determined by the concentration of the sodium chloride. Pure Marine salt has the highest concentration (98%) and is from a more sustainable source than mined rock salt.
Right place - GRITIT survey each site and site plans are agreed which specify priority areas where mechanical and pedestrian salt spreading and snow clearance will take place. Operatives access these plans on mobile devices when on site. This advance-planning ensures sites are not over-serviced with salt.
Right volume - spreading equipment needs to be properly calibrated and maintained to ensure the correct coverage and spread rate of the salt.Trained operators (LANTRA or equivalent body) know the correct volume of salt to spread according to the temperatures and ground conditions. The right level of salt, and no more, needs to be applied to be effective to keep premises free from the risk of ice.
Roads and paths preventative maintenance
In freezing conditions salt does offer some degree of protection to surfaces; when water gets into damaged or porous surfaces and then freezes the expansion that occurs leads to the materials breaking down.
In hard areas that regularly collect larger or deeper pockets of water, salt will only go so far to prevent freezing. Not only is the risk of injury from ice higher, if standing water and holes are left unmaintained and unsealed, regular freeze then thaw will break up the tarmac surfaces.
Carry out preventative measures and small repairs to avoid problems and costly repairs at a later date. Maintain clear drainage in the areas where there are depressions or holes and look for signs of damaged surfaces:
- Loose material sitting on top of the surface
- Deep line cracks opening up
- Breakdown or wearing away of joints and/or sealing material
- Crocodile skin appearance to surface
- Depressions and water pooling
Up-to-date techniques, such as infrared pothole repair, mean long-lasting repairs can be done quickly and with very little disruption to your site - so it’s no longer a matter that property managers wait to ‘batch up’ repairs to make a job more worthwhile.
For all your outdoor winter maintenance advice check our news area regularly and contact us.