Ordinary lawn maintenance
Ordinary lawn maintenance involves operations restricted to the turf grass or the surface layer of the underlying ground without damaging it, or causing damage that will be repaired within a matter of days. These operations can consequently be repeated several times a year.
Ordinary lawn maintenance operations include thatch removal and verticutting. Both these operations involve the use of a machine. This may be the same machine regulated in a different way. The difference between them is that the former only involves the blades of grass, while the latter also cuts into the surface layer of the ground and is consequently more energetic.
What is thatch?
thatch is formed by living and dead organic matter that is slowly decomposing on the surface of the ground, consisting of:
- leaf fragments, especially from trees and bushes;
- quantitatively prevalent fragments of stalks, stolons and roots;
- living stalks, stolons and roots.
The plant remains that accumulate are those that decompose most slowly (i.e. nodes in stalks, stalks and roots), as they are rich in lignin.
Lawn mowing residue, on the other hand, decomposes much more quickly and therefore does not accumulate in normal conditions.
CAUSES
The factors that contribute to its formation are:
- excessive nitrate fertilization;
- presence of particularly vigorous species;
- excessive watering and water build-ups (ground asphyxiation);
- insufficient annual mowing;
- sudden changes in the cutting height;
- creation of acidic conditions in the soil;
- lack of sufficient dampness for encouraging microbic activity.
Positive effects of thatch (moderate presence)
- makes the lawn more elastic (playing surfaces);
- protects the ground and the base of the lawn from direct sunlight, sudden changes in temperature and the effects of raindrops;
- reduces the negative effects of walking on the grass.
Negative effects of thatch (excessive presence)
- reduces resistance to high and low temperatures and drought
because the thatch enables the meristematic tissues (crown), the rhizomes and the roots to develop above the surface of the ground, meaning that they are no longer protected by it; - attracts parasites and insects
because the thatch houses and encourages the development of parasites, including Sclerotinia homeocarpa, Rhizoctonia, Helminthosporium, Typhula incarnata, …and because it reduces the effectiveness of fungicides and herbicides. - reduces the anchorage of the turf grass to the ground;
Symptoms of excessive thatch may include:
- persistence of human footprints;
- appearance of chlorotic patches;
- widespread diffusion of some diseases and infestations;
- presence of impermeable areas.
How to act
- examine the profile to check the thickness of the thatch and then intervene when it exceeds 10 mm in the case of cutting heights of under 25 mm, or when it exceeds 15-20 mm with higher cutting heights.
Thatch Removal
Equipment features
- thatch removers generally consist of a horizontal rotor fitted with utensils that do not touch the ground during the operation;
- they are fitted with components that operate with teeth (thatch remover) or blades (verticutter) within the lawn, without touching the ground;
- the teeth are assembled on elastic supports (springs) – the spring causes a very effective “ripping” action that damages the blades of grass very little;
- the teeth are normally spaced 15-30 mm apart;
- the blades may be hinged or fixed and produce a very energetic vertical cutting action that, as well as removing the thatch, also reduces the luxuriance of the lawn and combats the grain effect, or rather the tendency of some species to develop in a prostrate fashion;
- fixed blades are particularly effective at combating the grain effect;
- fixed blades are normally spaced between 18-55 mm apart (the tools with smaller gaps are more effective for thatch removal);
- the cut residue can be collected directly if the tool is equipped with a collection basket, or by using a vacuum or horizontal blade lawn mower with collection.
Precautions
- make sure that the lawn is well rooted in order to avoid pointless damage;
- regulate the operating depth carefully – it should not exceed 2-3 mm within the thatch;
- when the thatch is abundant, it is worth while running the machine over the lawn two or more times in different directions (star operation);
- it is a good idea to fertilize the lawn after the operation;
- avoid performing this operation during the weed germination period.
Time of year
- late summer / early autumn or early spring (depending on weed related problems);
- after the operation there should be at least 4-5 weeks of good conditions for lawn growth (average temperature, good humidity levels,…) before the growth spurt becomes too excessive or the winter period arrives;
- if necessary, this operation can be carried out at any time during the vegetative season.
Verticutting
Verticutters always perform a thatch removal operation too. Some models can operate as real thatch removers if it is possible to regulate the utensils so that they do not touch the ground. The utensils interact with the blades of grass and the ground, making continuous cuts for the main purposes of:
- aerating the surface layer of ground;
- encouraging water infiltration;
- removing thatch energetically;
- improving the effectiveness of fertilization and reseeding operations.
The work depth rarely exceeds 60-80 mm and use of the lawn is suspended for several days.
They may consist of
fixed or hinged blades assembled on a horizontal rotor (verticutter) which rotates in the opposite direction from which it moves, activated by a mechanical drive (self-propelled equipment or by the tractor power plug);
also very effective in thatch removal, they are used when it is necessary to regenerate the lawn through fertilization and reseeding and when it is necessary to aerate the surface layer of the ground (work depth normally under 50 mm – spacing between blades from 25-30 to 50-60 mm);
Time of year early spring at the same time as fertilization (and reseeding).