Posted on behalf of Prof Derrick Moot.
The photos below are from a sub clover drilling of a 400 ha area in Middlemarch in March 2022.
A lack of autumn rain meant the germination did not occur until May. Fortunately, sub clover seeds are capable of sitting in the ground and waiting for rain if drilled in a dry autumn. They will then germinate and grow into a rosette in winter until the days start to get longer. At that point the runners start to emerge which produce self-fertilizing flowers. You can see the runners, now up to 40 cm long, colonising the bare ground in these photos. The flower is the white flower (not the yellow flower). Each flower produces 3-5 seeds and the seeds closest to the centre of the plant are the most mature. At this time the first burrs have pegged into the ground and set seed. The farmer is leaving this area ungrazed for another couple of weeks to maximise seed set before it dries off. When the soil dries – any stalks attached to burrs that have buried their seeds will break off with grazing – it is good to pull up a runner and see if they break off before grazing – otherwise sheep will eat those little packets of protein. This pasture is being set up to turn the 10 kg/ha sown in to 500 kg/ha of seed for the coming years!