PASTURE

PASTURE MANAGEMENT is a subject that always seems to be more art than science, and it’s even more difficult on a block as there are never enough paddocks to get a good grazing rotation going. It’s difficult to give pasture plants enough time to recover and build up bulk before they have to be grazed again.

Pasture is not like purchased feed in a bag. Grass and clover changes every day of the year, and even during the day, depending on the sunshine-making nutrients created by photosynthesis.

The basic principle is simple: pasture feeds stock, and stock control pasture to keep it in its nutritious green leafy stage, which is high in protein and energy, low in fibre and highly digestible. Pasture plants are hard-wired to grow fast to the seed head stage to reproduce, and then die back until the next season. Pasture management’s aim is to stop or delay the plant from going to seed.

The ideal way to achieve this is to graze paddocks in rotation (rotational grazing). But the more usual practice is to ‘set stock’ where animals continually graze the same area so plants never get time to build up leaf area, and hence root reserves. This happens especially when paddocks are overstocked due to all the extra mouths to feed before young springborn stock are weaned and sold off.

If you didn’t have a ‘spring flush’ on your farm, there are two simple reasons: too many stock and/or low soil fertility, and both need to be fixed. The ideal stocking rate is what you can carry through winter without them getting skinny. You don’t want them coming into spring in low body condition with no milk for their offspring. These animals will never get back into good body condition and are more prone to health problems like internal parasites.

If the grass is not growing, it’s tempting to apply a top dressing of nitrogen fertiliser (eg 25kg/ha of urea) to give what grass you have a boost. But this will be a