Spring grazing management

Putting spring into your pastures in the high rainfall permanent pasture zone 

In spring, pasture growth is faster than your animals can eat it. What can you do?

 The first, and most important step, is to assess each pasture paddock on your property. 

 1. Very good quality, dense pastures of perennial grass and sub clover can either be left ungrazed (or lightly grazed) or cut for hay or silage. Pastures should always be grazed, if possible, in spring. So, if you are consistently understocked from September to late November, then consider changing your time of lambing or calving so you have more livestock pressure on your pastures in spring.

 2. Very poor weedy pastures containing no perennial grasses or clover can be “taken out” using a knockdown herbicide containing glyphosate. Following this spray, they can be sown to a brassica fodder crop, or grazed over summer as “hay frozen” dry standing feed, then resown the following autumn. 

If the paddock contains more than 500 plants/m2 of guilford grass and your soils are acidic, then consider using a sulphonyl urea herbicide. These products will knock out clover, so you will have to reseed the pasture next year. They also have a long plant back period, which may not allow some summer fodder crops to be planted in spring. 

 3. In between the extremes mentioned above, there are pastures in varying degrees of degradation. Consider the following.

  • Apply grazing pressure in spring to keep paddocks short – to less than 6 cm tall - and don’t allow annual grasses to run to head. This will encourage clovers and perennial grasses. When the paddock starts to dry off, take livestock out and rotationally graze over summer, to maintain at least 70% ground cover and 800 kg/ha feed on offer.
  •  Cutting silage will remove annual grass seeds, and other weed seeds, and “pickles” them. Silage allows the paddock to recover quickly, as silage can be cut earlier than hay, and removed from the paddock faster.
  •  Use chemical pasture topping. Various products can be successfully used to reduce the quantity of annual grass seeds produced in spring therefore reducing subsequent germination the following autumn. This technique can be used on pastures with heavy infestations of weeds such as silver grass, barley grass, brome grass and annual ryegrass. Timing of spraying is important as only a low rate of chemical is used. If the paddock is particularly weedy and comes to head unevenly then use the “knock out rate” as mentioned in 2 above. If the paddock contains clovers, then seek advice, as chemical pasture topping may reduce clover seed production. Grazing management to achieve even head emergence of the target grasses before spraying ensures a more reliable result, so ideally graze the paddock heavily during early spring and remove the stock two to three weeks before spraying.   Light stocking leads to selective grazing and uneven head emergence, and no stocking at all is preferable to this.

4. You should ask the question – why did the pasture deteriorate?

  • Inadequate fertiliser or highly acidic soil? Does the paddock require potash? How long ago did you test your soil for nutrient levels?
  • Have red legged earth mites or lucerne fleas eaten out the clover in spring? This is common in paddocks closed for hay.
  • Was the new pasture cut for hay or silage in its first year? This is not recommended.
  • Was the new pasture sown with a cover crop, which smothered it?
  • Was the new pasture smothered with annual grass weeds because the paddock wasn’t sprayed out the previous spring?
  • Has the paddock been cut for hay most years?
  • Has the paddock been grazed bare over past summers especially around stock camps?
  • Is the paddock too large resulting in patchy grazing pressure?

You should correct these problems before sowing a new pasture, and to make sure your existing good pastures don’t deteriorate.

 A well-managed perennial grass/sub clover pasture should last forever, and spring is the most important time to ensure this happens.

 In years with minimal (or non-existent) spring feed surpluses, whilst stressful for livestock managers, everyone has commented how good the summer feed quality has been, not to mention lower red legged earth mite numbers the following autumn.


Don’t forget that surplus feed in spring can cause as many problems as lack of feed, such as

  • Poor quality dry feed for livestock especially weaner lambs.
  • Grass seeds.
  • Builds up of red legged earth mites, and other insect pests such as slugs and snails.
  • Poor clover regeneration.

For those wanting more information on pasture assessment, refer to the MLA Pasture Paramedic technical manual.

For further details contact Tim Prance at Mob: 0427 812 655 or your local agronomist.