How new pasture is managed over the coming year will significantly affect its future persistence and yield.
By the time your new grass and clover seed is in the ground this autumn, it can be a relief to reach the end of a job you began ages ago. But in reality, some of the most important work is yet to come.
New pasture has the potential to grow a total of 150 tonnes (t) of dry matter (DM) per hectare (ha) during its lifetime. That’s why pasture remains such an important source of feed for New Zealand farmers. It doesn’t achieve that sort of growth on its own though – it needs your help, particularly during establishment.
Allow 12 months for establishment
Successfully establishing resilient, healthy pastures can take longer than some farmers realise. The job can’t be considered complete until new pasture has successfully survived its first summer. In other words, you need to allow 12 months for establishment.
The goal is to have big, healthy ryegrass plants, with 20-30 tillers each, before next summer. This gives pasture every chance of weathering what could well be a dry summer before settling down to a productive, high-performing future.
Grazing newly sown grass at the right time is the first step in this process. It promotes grass tillering, growth and pasture density, and should happen as soon as the pasture is ready.
Delaying the first grazing slows establishment and can reduce yield by up to 1t DM/ha. It also affects your clover, because clover seedlings are slower to establish and can be shaded out by more rapidly growing grass.
A good way to test if new pasture is ready for its first grazing is to try to pull grass seedlings out of the ground between your thumb and forefinger. If you can’t, it’s time to bring in livestock. Calves are best, if you have them, because they are lighter than cows. However, if cows are the only option, put them on new pasture for just an hour or two, but be careful of overgrazing.
Only two to three centimetres (cm) should be nipped off the top of the plants, which will be approximately eight to 10 cm tall at this stage. Where possible, the first grazing should be done in fine weather.
Weeds can grow faster than pasture seedlings
The next step towards good establishment is eliminating broadleaf weeds while they are still small, either before or after the first grazing. Weeds can grow faster than pasture seedlings and require less soil moisture so if they get away early they can compromise all the hard work you have put into the new pasture. This is especially important in dry autumns.
Bigger weeds are harder to control and they need more herbicide, so it’s good practice to spray weeds while they are young. You can stay one step ahead by inspecting new pastures closely on a regular basis, and taking prompt action if needed. By the time you can easily see weeds from your farm vehicle or bike, they have already affected the future growth of your pasture.
Looking further ahead, from the second grazing onwards, new pastures will grow rapidly and should be grazed to an appropriate residual, usually 1500-1600 kilograms (kg) DM/ha to encourage ryegrass to continue tillering, and to avoid shading the clovers.
For more advice about the timing of the first grazing and appropriate broadleaf weed control in newly sown pastures, get in touch with your local Fonterra Farm Source TSR today.
Article supplied by Agriseeds