AU714196B2 - Method of and turf product for erosion control - Google Patents

Description

I

METHOD OF AND TURF PRODUCT FOR EROSION CONTROL This invention relates to a method of erosion control and a turf product which is specifically adapted for use in the erosion control area.

It is often desirable to retain soil in areas where erosion is likely, say, in banks or cuttings or the like around roadwork so that the area can be stabilised and growth can be encouraged and subsequently act to bind the soil of the area against later damage.

ge e Various approaches have been taken to do this. For example, the location of a netting fabric over the surface, placing other material, such as, say, wood chips over the surface and possibly retaining these with a netting or the like and direct planting of shrubs or the like onto the surface.

If it has been required to grass the surface, this has been done by placing turf there over but, in general terms, this has not necessarily been completely successful.

The principal object is to provide a turf product which can be used in various applications but which is particularly useful in the erosion control area and also to provide a method of erosion control which basically uses this turf product.

-3- This combination provides a product which has good stability and can readily be handled but which, once located, is readily retained in its located position.

The invention also includes a method of manufacturing a turf product which includes the provision of an impervious layer, locating a root matting on the layer in association with a reinforcing mesh or the like, and locating there over turf, the roots of which can pass through the mesh and matting combination and can provide a stable and strong product.

"o It is preferred that the turf is located on the mesh and matting combination in the form of a o washed turf having a strongly formed root system but it would be possible to grow turf thereon either from seed or stolons if this is required.

The invention also includes a method of erosion control comprising preparing the surface to be protected and laying on this surface a turf product as hereinbefore described, the arrangement being such that the product will tend to remain on the surface without moving, although it can be pegged or otherwise connected thereto or could be top dressed with sand or soil to ensure that there was no movement, the arrangement being such that the root system of the turf passes through the matting into the ground's surface to thereby consolidate the surface.

In order that the invention may be more readily understood, we shall describe the formation of the product, the product itself, and its use.

-4- Particular embodiments of the turf product will be described in terms of the accompanying drawings: Fig. 1 is a schematic representation of a jute matting incorporating a reinforcing mesh.

Fig. 2 is a schematic representation of an embodiment of the turf product with turf growing through a reinforcing mesh and an underlying matting.

0000 In a preferred form of the turf product turf, preferably in the form of washed turf, is lain S (Figure 1) over jute matting 10 which incorporates as an integral part thereof a plastic reinforcing mesh 20 which is effectively sandwiched between the upper 11 and lower 12 sides of the jute matting.

*o Although in this preferred embodiment jute matting is used it may be of sisal or could even 0S •be of plastic or any other appropriate fibres. The form and thickness of the mat can also vary depending upon the required strength of the completed product as can the reinforcing mesh.

Thus the precise material of the matting is not germane to this invention except that it is preferred that it be of some fibrous material, through which roots can readily pass, and which will of course mat appropriately. In addition the exact material of the reinforcing mesh can be varied as can the particular design of such a mesh although in this preferred embodiment of the invention the mesh consists of rectangular plastic elements.

In another embodiment of the invention (Figure 2) a reinforcing mesh 30, which consists of an underlying mesh layer 32 affixed to an overlying convoluted mesh layer 31, is positioned on a fibrous layer 40. The turf, preferably washed turf, is then positioned over the top of the reinforcing mesh layer such that its roots 41 subsequently grow through both the reinforcing mesh layer 30 and the fibrous layer 40 and are then able to penetrate into the ground 50 and bind the turf product to the ground.

Again the types of mesh and fibre used can be of any appropriate kind however a plastic ,r reinforcing mesh of any chosen shape and a jute matting are preferred.

Oere *o°q °o S It is also preferred that the product be initially grown on an impervious surface and a plastic 08•O sheeting surface or the like can be provided which acts to control water flow but which, at the same time, acts as a barrier against root transmission. In each of the embodiments described above the turf product can be grown above such an impervious layer.

o. S If required, we could put top dressing such as sand on the turf, but in most applications this would not be necessary. The turf is then permitted to grow, under controlled or more or less controlled conditions to facilitate growth as much as possible. That is, a specific watering S: regime may be used and, if required, fertiliser can be applied to the surface, normally with the water.

-6- We find that the root system of the turf rapidly passes through the mesh and mat combination and contacts the plastic or other impermeable surface, and tends to mat by moving along the area between the fibrous mat and the plastics material.

At this stage, there is provided a product which is inherently strong, the reinforcing mesh giving it directional stability and the combination of the roots and the mat providing an overall structural rigidity.

*see or At that time, the product can be rolled and prepared for transport. Depending on the distance for transport and other parameters, the product may well be treated with chilled water before 4°.

rolling, to bring the overall temperature down, and, after rolling, particularly if ambient temperatures are high or the distance to be travelled is great, could be placed in a refrigerated container or the like.

°•o0e °In use, it is only necessary to prepare the surface over which the product is to be laid, locate it, and unroll the product. Where there are a number of rolls being used, to make contact between the adjacent ends and sides of the rolls.

S*4 Depending on the surface on which the product is being located, it can be held relative to the surface by pins or pegs which pass through the product into the surface.

r -7- Because of the overall formation of the product and, specifically the reinforcing mesh, any tendency to move will be resisted, and because of the general weight of the product, this may be all that is required.

Alternatively, or as well, the product may be top dressed with sand or soil to provide additional weight and to act to further prevent movement.

As the root system enters the ground's surface then the product itself will resist any form of 0. 00 movement and, ultimately, there will be a high degree of binding between the surface and the EO0* S product will then become integrally fixed to the surface.

:00 o If the product is being used on a relatively flat area, then, of course, it may well be unnecessary to take any steps whatsoever to hold the product.

S'S.

oIt will be seen that the product of the invention is basically simple in concept but enables a

S

S ready method of consolidating surfaces vulnerable to erosion and particularly surfaces which would be difficult to grass, either by growing grass from seed or planting stolons, in both of which cases, should there be any rain, the seed in particular, can be washed off the surface and there can be erosion before there is sufficient coverage. With normal harvested turf, which does not have the structural rigidity of the turf product of the invention, there would be a tendency for movement under these circumstances.

Claims (9)

1. A turf product comprising matting of a fibrous material in association with a reinforcing mesh to give directional stability thereto, and turf located above the matting and mesh with its root system passing thereinto, the turf initially being grown above the matting and mesh with its root mass passing there through onto an impervious surface which acts as a barrier to root transmission such that the roots tend to mat above this surface, when the product is moved to its required position, the 4e*. .00 roots pass into the underlying surface. 00

2. A turf product as claimed in claim 1 in which the reinforcing mesh is incorporated r "within, and is integral to, the fibrous matting.

3. A turf product as claimed in either claim 1 or claim 2 in which the turf is located *0e* ,9 eabove a reinforcing mesh which is positioned on a fibrous matting with the root mass of the turf passing through both the mesh and the matting.

4. A turf product as claimed in any one of claims 1 to 3 in which the fibrous matting is of jute.

A turf product as claimed in any preceding claim in which the turf is a turf layer.

6. A turf product as claimed in any preceding claim in which the turf is washed turf.

7. A turf product as claimed in claim 6 in which the turf is grown from seeds or stolons.

8. A turf product as claimed in any preceding claim wherein when the turf is grown the turf product can be rolled up or otherwise packaged for transport to any site where it is to be used.

9. A turf product as claimed in any preceding claim wherein when the product is moved to its required position it is affixed to the underlying surface. C .s a C S C *CC* A turf product substantially as hereinbefore described with reference to the accompanying drawings. S a DATED S S S r t this 19 day of March, 1999 JIMBOOMBA TURF COMPANY PTY. LIMITED By its Patent Attorneys A TATLOCK ASSOCIATES CC C. C C C C CC C' q CC