Making Grazing Last Through Winter

Judging by the temperature, the growing season of grasses will soon be over as it is getting too cool for them, especially at night. Even if we get more rain, the grass will not grow again if it stays this cool.

Surplus soil moisture will then be carried over to the next growing season (starting September this year) and cause an early green flush of perennial grasses.

Very good for our livestock, which will be desperate for green feed at that time of year.

The grass that is on your farm thus has to last until the next effective rains come (10mm or more in one day), hopefully by December 2014.

Do you have enough grass to last your livestock the next 8-9 months? How can you balance the number of livestock with the available grass? Easy, if you can visualise a rectangular bale of grass hay in your mind’s eye:

A medium-sized cow eats about two-thirds of a rectangular bale of hay a day.

In a week, she needs about five bales of hay. There are about 40 weeks in nine months, so a cow needs about 200 bales of hay to go through this year’s winter until rains come in December.

If you have 100 cow-sized animals on your farm, you need 20 000 bales of hay to feed them all this winter. That’s the demand side. Now, how many bales of grass grow on your farm?

A rectangular bale of hay weighs about 20kg. How big an area of grass on your farm do you have to cut to get 20 kg of grass? This is for you to figure out. If you cannot imagine it, take a “skaapskecircr”, get down on your knees and clip 20kg of grass.

Measure the area that was clipped. We rangeland scientists spend quite a lot of time on our knees. Now you know why.

If the grass is still green, clip 10kg extra into every bale. It’s been a good rainy season, so it’s quite possible that 20 kg of dry grass were growing on an area of 100 m2 on your farm.

That’s a quadrate of 10 long paces a side. Quite small. But remember, you need 20 000 of these quadrates to feed 100 medium-sized cows. And that’s before including the inevitable losses.

So that’s the supply side, and if it matches the demand, your animals will have enough to eat this winter.

If you farm with small-framed cattle, 100 cows will need only 16 000 bales. Hundred large-framed cows will need 24 000 bales. 100 Dorper-type sheep will need 5 000 bales and 100 Karakul or Damara sheep will need 3 500 bales.

Goats don’t eat much grass in winter, so this calculation doesn’t apply to them.

We need to buffer this calculation with some safety factors, because nothing in nature is ever 100% efficient.

Those bales of hay you “saw” growing on your farm get eaten by a lot of things: oryx, hartebeest, locusts and termites, just to mention a few.

If you have a lot of them, increase the number of bales needed to feed 100 of your animals by a certain percentage that makes you feel safe.

If there’s a lot of annual grass and little perennial grass on your farm, decrease the supply side by 30%, at least.

Annual grasses just gets blown away in winter and are not persistent. If your “mind’s eye bale” includes a lot of stick (Aristida) grass and other unpalatable grasses which animals don’t like, reduce the supply side even more.

After all this, how many “bales of hay” are on your farm now? And how many do you need? Does your supply match the demand? If not, get rid of some animals now, while they are still in good condition and before everyone else has to sell and prices go south quickly.

Or, buy in some extra feed now while it’s still cheap because no-one else is buying this early. But don’t hope early rains will save you! Better be prepared and have enough time to make some biltong.

Source : The Namibian