Animal health and performance is dependent on the quality of the pasture available, which in turn is reliant on sufficient mineral and moisture available from the soil.
We had the privilege, prior to Christmas, of visiting a Collingwood grazing property with stock as good as it is possible to see anywhere in the country.
Without exception all animals were big framed, deep bodied, glossy coated, clean, and not excessively fat. Typical of stock fully fed on pasture of exceptional quality, they were inquisitive and playful but docile.
Rapid animal growth rates without the need for high energy supplement and regular use of animal health remedies can be achieved by ensuring soil health is robust at all times. The annual application of dolomite applied at the rate required for optimum plant magnesium levels is an excellent first step.
At this time of the year soil moisture or the lack of it is foremost in farmers and growers minds. With pasture roots able to penetrate and access moisture to a depth of 0.8m (30 inches), it takes a prolonged dry spell to deny plants sufficient moisture for measurable growth.
Often the most noticeable change pasture in January and February is the change in colour. Brown does not mean growth has stopped. In spring pasture dry matter is often as low as 18% dry matter compared with recently cut pasture averaging 24% –27% dry matter. The eye needs to be recalibrated to ensure that the quantity of short brownish summer pasture is not underestimated.
Brown does not necessarily mean lack of quality either. High quality hay can be an excellent source of feed while summer pasture of the same colour and similar composition is often regarded as second rate. Careful observation of animals grazing short brownish pasture is the best means of ascertaining both quality and quantity.
We have at present hinds grazing apparently dry brown pasture that are at least maintaining weight as well as rearing exceptional fawns. A close examination of the pasture reveals green leaf close to the soil surface, and because there is plentiful feed due to excellent December growth, and the troughs are clean, all animals will continue to perform well over the next month even with little rain.
On physically well-structured soils moisture is able to move both downwards and perhaps a little surprisingly upwards. The rate of moisture movement upwards may not be rapid but is often sufficient for plant survival ensuring significant response to even small quantities of summer rain.
Some years ago a farmer client related the story of the farm of two halves. One half was managed by the owner the other by a sharemilker. Stocking rate, contour, and pasture management was little different as was production throughout spring and summer.
With the arrival of summer rain one half of the property visibly changed colour more rapidly than the other with a corresponding lift in pasture growth. After careful thought the owner attributed the more rapid response to the dolomite that had been applied in winter to that half of the property.
The rate of application on intensive dairy properties is usually 220 – 250kg of dolomite (25kg – 28kg Mg) per hectare. On grazing properties it may be as little as half or may be applied at the dairy farm rate once every second year.