what are moss and algae and how can they be controlled?
Public spaces, green spaces and community use areas can all be affected by moss and algae. Moss, algae, liverworts and lichens can all be found growing on hard surfaces such as block paving, concrete pathways, steps wooden decking and benches, tennis courts and pavements. As neither moss nor algae have true roots, they do not damage the surfaces in general but do cause hazards to members of the public, and residents when they become wet or in frosty and icy conditions.
Moss
Mosses date back 450 million years and comprise of 15,000 to 20,000 species and unbelievably occur on every continent and eco-system, forming a green carpet type mass, usually found growing on damp, light restricted areas. Block paving is particularly prone to moss growth as it thrives within the cavity between the pavers. Mosses are none flowering plants and produce spores for propagation, they have stems and leaves but instead of roots they have rhizoids which are small structures resembling hair
Liverworts
Liverworts are a type of moss. There are estimated to be 6000 to 8000 species of liverworts, which can grow on hard surfaces such as concrete, tarmac, wooden decking and street furniture and monuments. Characteristically it has a green flat plate type body with no leaves present. One common and eye-catching example would be Marchantia, this species is often topped with a structure shaped like an umbrella with spores held in small capsules.
Algae
There are more than 30,000 species of algae, including aquatic algae which come in a variety of colours from red, green, brown and a yellowish brown. But for the purpose of this blog, we’re concentrating on green algae that is commonly found on external wooden benches, block paving and concrete surfaces such as a car park. Algae is most recognisable as a powdery or film like deposit usually on garden furniture and prevalent on stonework. Cyanobacteria or “Nostoc” is often mis-identified as algae, but to a trained eye the green or black jelly type growths that appear in damp cooler weather make these stand apart from algae. As with mosses, algae lack true roots and are classed as photosynthetic organisms and often form colonies.
Lichen
Lichen are symbiotic fungi and algae species. They form a silvery crust like structure commonly found on garden furniture and benches, can also be found on street paving and within urban settings. Appears crust like and in some instances leafy. Lichens are not a single organism; they are a stable symbiotic association between algae and a fungus and/or cyonbacteria.
Where is the problem?
Multi Use Games Area (MUGA’s) and tennis courts require regular and proactive maintenance to keep them in good order, if moss and algae are allowed to build up on the surface of the MUGA, water will not drain off and then flooding or water logging occurs making the surface and the facility unusable. In general, having excessive moss within fine turf, lawns and on sports fields is due in part to the grass struggling either by environmental impacts such as low light, compacted ground and excessive moisture. If grass areas are left untreated the moss within the turf will eventually outcompete any grass within the surface. Hence the grass will die, which can obviously be a huge headache for managers of sports grounds such as:
- Football pitches
- Rugby grounds
- Cricket grounds
- Bowling greens
How can they be removed?
Moss and algae can be effectively controlled with the right treatments – but it must be done at the right time for optimum efficacy.
Environment controls uses several methods for controlling moss, algae and lichens depending on the surface types, including chemical application and mechanical methods. A bespoke management plan can be put together depending on the affected sites and their usage. These treatments are best carried out within the winter months although we have to admit that severe icy and wet conditions are not ideal as it can affect the efficacy of biocide treatments, but carefully planned and managed, we can work around the weather.
Why treat in winter?
Winter is perfect for most mosses, algaes and lichens to be treated, and we have found the most cost effective solution is to have multiple grounds treated in one day, so we offer a fixed price multi-pitch contract to help with budgeting.
Tackling moss within turf areas can be a multi-faceted approach, moss tends to encroach into grass areas over the winter months, this may mean an application of moss control before any scarification of the area takes place as this eliminates the risk of the moss spreading its spores.
Moss on a sports field can lead to the lack of a decent quality playing surface, leading to excess surface water, the moss dying off in the summer leaves large bare patches also water gets held near the top of the surface which encourages areas to sit wet which in turn results in a thatch build up.
Conclusion
Mosses and algaes are a real problem for individuals but mostly for Local Authorities and Property Management companies and leisure facilities organisation responsible for keeping public areas looking nice and remaining safe. As moss and algae thrive on hard surfaces, this pretty much covers all aspects of property maintenance, from pathways, drives, hard-standing areas and leisure facilities. having a yearly plan in place will avoid excessive grow back, and can be more cost effective if multiple sites are covered by a single contract. Winter is ideal for treatments as it will limit or stop growth in summer when higher usage is expected.
If you’d like to speak to us about anything in this blog please email contact@knotweed.co.uk and title your enquiry ‘MOSS & ALGAE’