Reports from farmers indicate that swards of 1,500kg DM/ha and above have started to develop stem in the last week or so.
This is a regular occurrence as the heading date for popular ryegrass varieties is in the latter days of May.
The main reason that grasses become stemmy is as a means of self-preservation; grasses will stem out and develop seed heads for reproduction.
Rye grasses will typically do this in the coming week or two, although stress on the plant due to a lack of nutrients or water will also cause swards to stem out.
1. Target correct covers
Target pre-grazing cover for all farms (drystock and dairy) should be 1,200kg to 1,400kg DM/ha and below for the next 10 weeks or so.
Allowing covers to become heavier than this will result in lower energy feed going into livestock, as well as increasing the risk of stem developing in swards.
2. Mow out heavy covers
Where growth is exceeding demand, a portion of the grazing block should be mowed out as silage.
Where farmers are concerned about running short on grass, the paddock can be mowed at a cover of 1,500kg to 1,700kg DM/ha and should be back in the rotation within three weeks.
Where the stocking rate is low, taking out paddocks in long-term silage to artificially up your stocking rate can work well, especially where not all paddocks are easily mowed.
Where there is a shortage of grass on farms, but the pre-grazing yield of a paddock is high, pre-mowing might be an option.
Pre-mowing involves mowing the grass with a disc or conditioner mower before allowing animals access to the paddock.
By doing this, you are removing the selective grazing of the animal and forcing them to graze the stem and leaf. It is not ideal and a better option is to mow and bale if possible.
4. Applying fertilisers
Fertiliser application, be it chemical or organic, should be kept up to date. As a rule of thumb, 0.8 to 1 unit of nitrogen (N) per acre per day should be applied, or 16 units/acre for a 20-day rotation.
Swards with a high clover content will require half of this, as the N-capturing bacteria in the root nodules of clover are in work mode at this time of the year.
Cutting back on N application at this time of the year can result in N stress on grasses, causing them to stem out at low covers. Utilisation levels are high at the moment as well, so keeping N applied will have a good return on investment.
5. Spring reseeds
Spring reseeds will be starting to come back into the rotation shortly.
A post-emergence spray to clear the new sward of weedlings should be applied two weeks pre-grazing.
The first grazing should be done at circa 1,200kg DM/ha. As a test, roots are sufficiently secure when you pull at the grass and no roots come away with the force.
After the first grazing, target pre-grazing yields of 1,000 kg DM/ha to allow the plant to tiller.