Last update: August 16, 2011 02:09:37 PM E-mail Print

 

Lewensgras (Phalaris sp.) - a success story?

 

F .A. Roux, Pasture Research Section

 

 

THE STORY OF LEWENSGRAS started when Mr Torr of the farm Bultfontuyn in the Middelburg district was given four tufts of this grass by a friend of his, Thomas Marais, who is a farmer in the Hofmeyr area.

According to Mr Marais, lewensgras was introduced to South Africa by a certain Dr Le Riche who visited the Russian steppe in the 1930's. There on location he saw this grass and asked the Russians if it was possible to get hold of some seeds or plants. This was out of the question. Luckily he was with a group of other South Africans in the veld. In Afrikaans he said to them: "Kyk, ons het die gras nodig. Ek gaan steel en julle gaan wegsteek." And in this way the grass was conveyed to South Africa. Thomas Marais was related to Dr Le Riche and through him got hold of some of the grass.

Mr Torr planted this grass on the farm Beaconsfield in the Hofmeyr district. The first thing that intrigued him about this grass was that it was very brack tolerant, lush, fast growing and frost tolerant. It did not take Mr Torr very long to realize that you could use lewensgras to get the most efficient usage out of your water, especially in the Karoo where water is the limiting factor and the efficient usage thereof is of paramount importance.

In 1981 Mr Torr moved to the farm Bultfontuyn in the Middelburg C.P. district where he continued to carry out trials. During this time he was visited by Dr Piet Roux, a former director of the Karoo Region. Dr Roux was very impressed with the grass and was a great source of encouragement and inspiration. Between 1981 and 1990 Mr Torr refused to sell any of this Phalaris strain because he was determined to test it to the utmost before selling any to his fellow farmers.

In 1990, after thorough organisation of this new enterprise, Mr Torr started selling the grass in batches of a thousand plants or more. Since 1990 over a million plants have been distributed throughout South Africa, Namibia and even to Paraguay. The feedback was most encouraging and a great percentage of the buyers wanted some more.

On Bultfontuyn there is approximately 12 ha of lewensgras grass under cultivation. Mr Torr is more than satisfied with the performance of Dorpers and milk cows that grazed this grass.

According to Mr Torr the grazing of lewensgras eliminates high capital costs and cuts back on machinery expenditure. He estimates that his cutback is at least 80 %. He claims that the cardinal feature of this grass is that there is no better way of utilizing available water.

During the interview with Mr Torr the following questions were put to him:

 

To what extent is this grass frost resistant?

Under irrigation it is completely frost resistant and is not dormant. It grows in winter, but at a slower rate.

 

How does lewensgras propagate?

Due to the fact that the seed is not viable, it is propagated by an efficient vegetative method.

 

What about weeding?

No matter how good the preparation of your soil is, you will always have a weed problem.

With the methods developed there is no necessity for weeding. Careful initial grazing and the hand application of fertilizer stimulate the grass tremendously and the weed problem is eliminated.

 

What about soil type?

The gras has been distributed all over the country and in the various soil and climatic conditions it has proved remarkably versatile. On Bultfontuyn the average soil depth is 100 to 150 mm. One of the aspects of this grass is that it is very resistant to water logging. In America, a similar species was introduced to reclaim marshland.

 

Can lewensgras be used for reclamation purposes?

Definitely, yes! Exciting results have already been obtained in gully erosion on the farm Grass Ridge of Mr Keith Collet in the Cradock area. At Cookhouse where a drainage problem is encountered, promising results were obtained. Even if this grass is covered with 120 to 200 mm of silt, it is not smothered and recovers well.

 

How frequently must the grass be irrigated?

Once lewensgras is established and an effective ground cover is formed, the periods of irrigation is extended. I am finding now that in the beginning where I irrigated weekly, we can now comfortably extend this period from 3 weeks up to a month. On average I apply about 32 mm of water fortnightly. During excessive heat and wind this amount is increased. Due to the fact that this grass increases the organic content on and in the soil, it decreases the evaporation rate.

 

What about fertilization?

This I've learned is a very important factor for the reason that the bulk of foliage produced is at least double with the application of fertilizer. Approximately 150 kg/ha of ASN is applied during spring and 150 kg/ha during autumn. The autumn application is the most important because this carries the grass through the winter and gives rapid stimulation in the July to August period.

 

What kind of grazing system do you apply and why?

I apply a heavy intensive grazing system for not longer than 3 days to allow the sheep to clean off the pastures. This has a very stimulating effect on growth. After 3 days the flock is rotated to the next small paddock. This in effect allows from 10 to 12 grazings on a pasture. This is roughly once a month on the same pasture. In essence this means the grass must be utilized to get maximum results. With strict management, I believe that with this system the opportunities of controlling internal parasites leaves tremendous scope for research. There is no purging at all, neither prussic acid poisoning, nor bloating. I still follow a dosing programme three times a year.

 

Do you ever apply supplementary feeding or licks?

No. This is a very important economic factor.

 

How long do you keep your Dorper wethers on this pasture before marketing them?

From the day of lambing, approximately 5 to 6 months. The average dressed weight obtained from abattoirs is 20 kg. The average grading was super and first grade.

 

What are the economic implications of this grass?

You are cutting down on your production costs very dramatically for the following reasons:

1-Drastic reduction on mechanisation and fuel costs.

2-Ultimately a big reduction on labour costs.

3-lncreasing the productivity of the soil and restoring it to nature's way of continuation of productivity.

4- The ability of the grass to sustain Itself through a dry period.

 

What is the grazing capacity one can expect from this grass?

If your system is running efficiently, there is no lack of water and fertilizer is applied twice a year, a grazing capacity of 40 SSU/year can be obtained.

 

How does one start off?

My advice to farmers is to start their own nursery. You let the plants grow out and develop. In the period from September to December/January it attains a

height of 1,5 to 2,1 m. At this stage the proposed pasture area or land must be prepared. Draw furrows with a cultivator approximately 80 to 100 mm deep and the row spacing 45 cm apart, or closer. One then cuts the stalks down to ground level with a sickle and lay the entire stalk in the prepared furrows. Lay three or four stalks alongside one another, maintaining a reasonable overlap. Cover it up and irrigate. A cardinal feature is that all stalks cut in the morning must be laid in the furrows. Covered up and watered on the same day. It is essential to cover it up and compact it firmly. The first irrigation must be adequate and thereafter the soil must be kept damp. March to October is the planting months. Weed is eliminated during this critical stage.

Surplus stalks can be put in a dam. Small roots and leaves develop in the nodes and within 2 months the plants are ready for transplantation. These long stalks must now be cut into individual plants and transplanted. The dam must have a regular inflow of fresh water to maintain the oxygen content of the water.

The Pasture Research Section at Grootfontein is investigating this grass. At this stage it is clear that it can produce a lot of material in a reasonably short time. Under optimum conditions (enough water and fertilizer) it can produce up to 20 t of dry matter per ha over a period of 4 months. If the fertilizer is left out, this figure is lowered to 11 t/ha.

A small plot of this grass was tested under dryland conditions. Initially 253 individual plants were planted during August 1990 and watered on the day of planting. For the rest of that year the grass depended on the rain. The following months were extremely dry and an average of only 2,9 mm was measured till the end of November 1990. During December the average rainfall was 31 mm and for January 1991 it was 44 mm. During January all the grass plants that have survived, were counted - 74 % was still alive.

Although the rainfall during December and January was good, the water stress experienced previously has taken its toll. The grass never really thrived afterwards. If it had rained sufficiently during September and October the grass would have performed much better under dryland conditions. With enough water and fertilizer (as suggested by Mr Torr), lewensgras can definitely play an important role as an additional pasture on the farm.

 

Published

Karoo regional newsletter 2