Moss develops and flourishes in buffalo lawns for three primary reasons. The affected lawn area where the moss is growing will need to be continually moist, will need to be growing in a high level of shade, and the lawn where the moss is growing will need to be weak… meaning the buffalo grass will need to be in a weaker state than the invading moss in the lawn.
Buffalo grass should be one of the very best grass types for defeating moss and stopping its establishment and further growth. This is because buffalo grass is a highly shade tolerant lawn type, and as such buffalo will flourish and grow and outcompete moss in shady areas.
While buffalo does have very good shade tolerance levels and can defeat moss in some shaded areas, we must remember that not even buffalo grass can grow strong and healthy under shade conditions which exceed 70%. So in environments where there is very high levels of shade, and excess moisture, the buffalo grass will still grow weak while the moss grows strong. So we can see we're still going to be facing moss problems under these conditions.
Killing and Treating Moss In Buffalo Grass
To kill or treat moss in buffalo grass lawns, we must make the affected area highly favourable to buffalo grass, and highly hostile to the moss. Which involves addressing all of the main environmental factors which encourage moss growth and make the lawn weak.
If we have moss in buffalo grass then we must have excess shade in that same area, otherwise the moss wouldn't grow and the lawn wouldn't be weak.
Remove excess shade by pruning all surrounding foliage from plants, bushes and trees. If the excess shade is coming from garden sheds, fences or other man made constructions, then we should look at removing these wherever possible if we still want the lawn to continue to grow in this same area.
If however we still want those structures which are causing the shade issues for the buffalo lawn, then it would be best to remove the grass in the affected area, and replace it with a garden path or a new garden bed with shade tolerant plants.
Moisture In The Soil
Healthy moss growth also requires high levels of moisture to be always present in the soil, and these same high levels of moisture will not only weaken buffalo grass, but make the turf highly susceptible to lawn disease as well. So we must remove all excess moisture from the affected area.
If reticulation sprinklers can be adjusted for the affected area then we must do so immediately, or otherwise stop or drastically slow down the watering in this area if using a hose and a sprinkler.
Aerate the soil properly and effectively. and the very best way to do this is with the use of a lawn coring machine which will punch holes into the buffalo turf and soil and remove plugs of the same matter in the process. These plugs should be removed from the turf after coring and the holes filled in with a free flowing sand, which will enable far greater drainage. Coring will not only need to be done once, but will need to be repeated as often as is necessary, which may be once a year or once every few years.
Apply wetting agents liberally twice a year in Spring and Autumn. Wetting agents allow for far greater free flowing of water throughout the soil profile, which should allow excess moisture on the surface of the soil to more freely flow away down into the water table.
Replacing Lawn Soil
If the soil beneath the buffalo grass naturally holds onto excessive amounts of water, such as with soils with high clay content, then the soil should be removed to a depth of 20 to 40 cm and replaced with a sandy loam soil. A sandy loam will more freely flow water around the entire roots of the buffalo lawn, but will also allow the water to flow away when it is not used by the turf itself.
Increasing Lawn Health
Finally in this battle between buffalo grass and moss, we want to make our friend the buffalo grass as strong as possible so that it can more easily defeat the moss, killing it, outgrowing it, and smothering it. So lets increase the health of the lawn as much as we can.
We've already increased sunlight, removed excess moisture, added some lawn loving oxygen into the soil from coring, now its time to look at nutrients… lawn food.
Begin a good year round fertilising program for your buffalo turf, using a high quality fertiliser with trace elements, and applying to manufacturers recommendations. This lawn food will greatly enhance the quality of the entire buffalo lawn, as well as making it so much stronger in the shade too, which in the end should easily outcompete and kill off that nasty moss in our buffalo grass lawns.