Wind erosion is a major problem on light sandy soils or exposed areas. Kikuyu with its sprawling root system or stolons above ground and rhizomes beneath the soil, move out to some length intertwining to create a web or carpet. This carpet covers the light sand particles locking them down and preventing the shifting of top soil off the paddock. It results in fertiliser remaining where it is applied. These exposed areas are often a financial loss with little or no return in cropping or grazing concerns. Low yields and low carrying capacity result.
It is costly to apply clay to these soils, but by growing kikuyu the cost of establishment is a once off and return for the financial outlay is soon generated. The light sandy soils are favoured by kikuyu as its roots are able to penetrate down 2.5 to 3 metres with ease. At Tamgaree we have used kikuyu to stabilise a number of wind prone areas which were degraded and have returned them to a productive and stable pasture.
The grade of slope and the catchment area for a gully or even just a water way, influence the volume of water travelling on its path down hill. Large rainfall events can have disastrous effects carrying soil and nutrients into our river systems and leaving behind scarred areas that may be difficult to revegetate.
As with wind erosion, the carpet effect of kikuyu ties the top soil down and water flows over the grass without shifting silt. We have had erosion develop on sloping country to a depth of 0.5 metre in places, which left unchecked would continue deeper and wider. We used earth moving equipment to fill in the gullies created and planted these areas to kikuyu. These areas are now stable.
Kikuyu has the ability to push its roots down to a depth of 2.5 to 3.0 metres to source and utilise ground water. Some of this is because of its tolerance to low PH soils which would inhibit other pastures. A PH of 3.7 (CaCl 2) PH is very acidic and kikuyu can handle this. However, it will perform much better with more neutral soils. As kikuyu grows for an extended period it draws down on the soil moisture levels and so reduces the ground water recharge. I have seen saline areas which were expanding halted. Kikuyu will grow in general, to where barley grass grows. One of many positive attributes.