February 01 2010
EARLY spring is a good time to check out the state of the white clover in swards, see how well it has survived the winter, and to plan strategies to manage it, says DairyCo extension officer Chris Duller.
“There won’t be a mass of leaf material at this time of year, but what is important to see is a good healthy stolon structure.
"Stolons are creeping stems that spread outwards across the surface producing roots and leafing points as they go. They act as an energy storage reserve for the clover plant as well as allowing the clover plant to spread.
“If there are lots of stolons that are 2 or 3mm wide, extend out for 20cm or more and have lots of rooting points then the plants are healthy and will cope with the pressure of the coming grazing season,” explains Chris. “If the plants are small with thin stolons and few rooting points there is a risk that if they aren’t managed carefully this spring they could disappear altogether.”
To encourage the recovery of small clover plants consider the following:-
- Check out and correct soil chemistry, clover plants are very sensitive to soil pH and P and K levels so pH of 6-6.5 and P and K indexes at 2 are essential.
- If you have sheep on the farm – keep them away from these vulnerable clover plants.
- Ryegrass starts growing at lower soil temperatures than clover. Graze off covers at around 2500kgDM/ha in early rotations to prevent grass from shading out the clover.
- Don’t be heavy handed with the nitrogen (keep early applications to around 25 kgN/ha), unless you are sure you can keep on top of the grass.
- If the field is planned to go into silage it is possible to bring it into the grazing block.
- Rotational grazing encourages clover growth more than continuous grazing – as long as covers don’t get too high.
“If you have a situation where clover has begun to dominate the sward and there is a mass of large healthy plants then now is the time to consider the reverse of the options stated above to try and impose some pressure on the clover,” concludes Chris.