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Moss

There are several different types of moss that can cause problems in amenity turf, but they generally colonise a weak sward. These are usually scalped, worn, nutrient deficient, drought stressed or wet turfgrass areas.

Mosses belong to a group of plants called Bryophytes which like most plants contain chlorophyll and photosynthesise to facilitate their growth and development. However they do not have typical roots but possess so-called rhizoids that help to anchor them to the ground and take up water directly through their leafy surface.

Moss plants don’t produce seed but release microscopic spores that can easily be spread across the turf and enter the profile to depth. The vegetative parts of the moss plants can also serve to increase its composition in an infected sward.
Moss can be a problem in turf all year round but its presence in the sward will be more apparent if turf becomes weak.

The silver thread moss Bryum argenteum is a common problem on weak or worn turf areas and once in the sward, it can rapidly become established and very difficult to remove. This moss in particular can have a significant and detrimental effect on the visual and playing quality of a close-mown, fine turfgrass surface. Other moss species have a more open growth habit than that of B. argenteum, but all moss invasions will change the quality of the playing surface and should be targeted for removal as soon as they are seen.

Effective and long-term control of moss in turf relies heavily on producing a strong sward that will out-compete the moss plants.

It is often said that ‘moss invades a problem and then becomes a problem’. Products aimed at weakening the moss plants should be applied when the rootzone is moist and when the moss is actively growing. One to two weeks after application, the moss plants should become darker in colour or show reduced vigour.

These weakened plants can be removed by scarification and the sward encouraged to fill

in through the thinned areas, thus reducing the conditions favourable for re-establishment of the moss. Since moss rhizoids can typically colonise the upper 20-30mm of the rootzone, deeper scarification will be necessary to remove the moss fragments and reduce its impact on the sward.

The upright and compact nature of B. argenteum in particular makes this a challenging moss to remove because applied products are not likely to wet / penetrate the plants but be dispersed across their surface.

Non-Pesticidal Silver Thread Moss (Bryum argenteum) Prevention

Effective moss management in turfgrass, particularly on golf greens, is essential for maintaining healthy and aesthetically pleasing playing surfaces. Key strategies include improving drainage to lower moisture levels that favour moss, managing soil compaction through regular aeration for better turf health, and optimising light and airflow to deter moss proliferation. Additionally, maintaining proper pH levels through regular soil testing and adjustments is crucial, as moss prefers acidic conditions. Implementing a balanced fertilisation regime tailored to the turf’s needs ensures optimal health and resistance against moss invasion.

Mowing practices also play a vital role in moss management. It’s important to avoid cutting grass too short, as this can stress the turf and give moss an advantage. In cases where cultural practices are insufficient, chemical controls such as different forms of iron can be implemented at different rates and volumes to manage the plant Ferrogranul, X-Xtra Iron and Lawn Sand timing of these applications should be predominantly made in the spring or the autumn. Integrated Pest Management (IPM) is another critical aspect, involving regular monitoring of the turf and prompt responses to the earliest signs of moss infestation.

Finally, overseeding with All bent the areas where moss has been removed helps establish a dense, healthy turf, which is less hospitable to moss growth. Efficient water management is also key, as overwatering creates ideal conditions for moss. By combining these strategies, turf managers can effectively control moss growth, ensuring the health and aesthetics of the turfgrass.