By Vinod Goyal | Agricare Corporation
The application of sand is in most cases used to maintain or improve the soil structure. In combination with regular aeration on heavy soils, one can over a number of years exchange the soil step by step. By repeated sand applications one can create a mini sand layer.
Regular small quantities maintain turf with well structured profiles, permeable for water, air and nutrients.
Through sand applications, the surface dries off more rapidly after rainfall irrigation.
Slight unevenness of the surface can be overcome by using a dragmat after sand application.
Light applications of 20 g/m2 of Lime, Dolomite or Gypsum before sand is applied are highly beneficial in that they prevent the sealing of the old buried surface. Light applications of 20 g/m2 will not alter pH, but will assist the breakdown of thatch via activation of microbial activity.
Sand Qualities Depending On The Desired Function
|l/m2||m3/Area (10,000 m2 = 1 ha)||Result|
|3-4||30-40||· Improved evenness of the surface
· Thatch layer reduction
|4-6||40-60||· Filling of core-holes|
|5-8||50-80||· Amendment of the top soil
· Build-up of the mini supporting layer
Timing for Sand Application
During the vegetative period from September to April the application of sand should be combined with a mechanical measure such as verti-cutting or aeration. In most sports turf cases, the sand application is done once during the summer playing break. On golf greens sand is applied in several doses as top-dressing. In most sports turf cases, the sand application is done once during the summer playing break. On golf greens sand is applied in several doses as top-dressing.
Sand meets the demands of improving the soil structure only if the following quality criteria can be met:
- Balanced ratio of different fractions (fine, medium and coarse sand)
- Resistance to mechanical wear
- Stability against decomposition
- Right pH-level
Washed sands with round granules will best meet these requirements.
Washed sand with granules 0-2mm or 0-4mm are preferred for sand application. Sand should contain only traces of small particles (<0.06 mm). It is important to use sands free of, or low in lime (<5% of CaCO3), in order to avoid blockages. An optimal granular size can only be defined having analyzed the current turf soil.
The distribution of sand has to be as even as possible. For both golf and sports turf areas, high performance distributors are used. After distribution and drying of the sand, a dragmat towed by a tractor assist good incorporation into the aeration holes and sward.