What is pasture? Pasture as a feed for stock

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1 PASTURE

2 What is pasture? Pasture is made up of different varieties (cultivars) of grasses, clovers and weed species, as well as bare ground and dung areas. The most productive grasses are perennials and annuals, e.g. ryegrass, cocksfoot, timothy and fescues. Unproductive grass species are Yorkshire fog, Browntop and Kikuyu. White and red clovers provide good feed for stock and improve soil fertility. Generally, good pasture is 70% ryegrass and 30% clover. For help identifying your grass type, see N.C. Lambrechtsen s book What Grass is That?. Pasture as a feed for stock Pasture provides the cheapest source of dry matter (DM) for stock feed, but it s not a balanced diet. Pasture growth varies in quality and quantity over the year depending on soil temperature at root level, soil fertility, and sunlight for photosynthesis. DM can be measured with special equipment or estimated by eye with experience. Ruminants (cattle, sheep, goats, deer and camelids) can only graze down to about 30mm, but horses, which have both top and bottom teeth, can graze lower. 106

3 Pasture management Good management is all about maintaining the pasture at a height that provides nutritious feed for stock. You should then use your stock to keep the pasture at its most productive, leafy stage. Pasture should not be grazed to very low levels, as not enough leaf will be left to generate new growth. Supplements such as silage or hay should be fed to allow the pasture to recover. Clovers need light, and don t thrive when companion grasses get too long. Rotational grazing is when stock move around the farm on a time schedule, allowing pastures time to recover. In spring the rotation time is fast and in winter it s slow. Set stocking is when animals stay in the same paddock all the time. This allows little opportunity for feed to build up. It s especially important to manage the spring flush when feed supply exceeds animal needs. This surplus feed should be made into silage and hay for feeding during winter and droughts. Pastures that have run out of good species (e.g. after a drought) need to be re-sown. Seek professional advice on how to do this and which cultivars to sow to suit your soil type and stock needs. The cheapest method is to over-sow seed into existing pasture after spraying what s left of the old pasture and weeds. If a sward opens up due to drought or poor grazing practice, weeds like thistles and ragwort will fill the gaps. A weed-control programme is important, as there s no point in letting weeds use valuable soil nutrients. 107

4 Soil fertility For productive pastures, the soil needs to have a ph of around It s also important to have adequate levels of the following nutrients: 7 N NITROGEN 12 Mg MAGNESIUM 15 P PHOSPHORUS 16 S SULPHUR 19 K POTASSIUM These soil nutrients should be measured on an annual basis with both a soil test and a herbage test. From a soil or plant test, a consultant can advise how much lime and nutrients need to be applied, and in what form. It s important to know the soil type on your farm, not only to supply the appropriate nutrients, but also to manage the pasture in winter. This will help you to avoid pugging and damage to the soil structure in wet conditions, which may take years to repair. Contact an appropriate laboratory for details on how to take samples. Rural supply stores such as Farmlands can organise soil tests for you. Alternatively, you can contact a soil testing laboratory or fertiliser company. 108

5 Stocking rate Pasture growth is very dependent on how much stock is run on the farm this is known as the stocking rate. The stocking rate is best measured by the number of stock the farm can carry at the start of winter 1 June. This is often expressed in the fairly crude measure of livestock units (LSU) where all animals on the farm are converted to a ewe with a single lamb. For example, a cow is 6 LSU. Finding out the ideal stocking rate for your property may require some professional advice, but if there s no visible spring flush, then either the farm has too much stock or soil fertility is too low. Both these issues need to be fixed before the following winter. SUMMARY Pasture provides the cheapest source of feed for your stock, so understanding it is vital to running a successful lifestyle block. Below are the key points to remember from this chapter. Generally, good pasture is 70% ryegrass and 30% clover, but this can vary due to location and livestock needs. Find out what type of soil you have on your property and ensure it has a ph level of around 6.5. Work out which type of grass species is best suited to your needs. Find out the ideal stocking rate for your property. We re here for the good of the country. 109