by Will Hansen – Agriseeds
Beneath the shimmering green sea of spring pasture covers, are millions of new-born ‘daughter’ tillers. Within a few months your pasture will comprise entirely of these new daughter tillers. They will replace their ‘mother’ tillers who have just been vernalised over winter, and will soon go to seed and die. How dense your pasture will be in summer depends on how many of these daughter tillers survive. Up to three daughter tillers can grow from the base of a mother tiller who initially provides them with water and nutrients. If, on average, two daughter tillers replace every mother tiller then your pasture will thicken up coming into summer. If less than one daughter tiller survives (for every mother tiller) your pasture will start to thin out.
Right now the fate of millions of daughter tillers beneath the sea of green covers depends on you. Apart from the water and sugars they initially get from mum, they need two things to survive: sunlight and nutrients.
Daughter tillers will not survive weeks of darkness under high pasture covers. They will turn pale, and die. This is commonly seen after heavy silage crops; pasture residuals are white, thin and are slow to grow back because most of the daughter tillers have died. There are three simple rules to follow to ensure your daughter tillers get enough light:
- Graze (or cut) at 2.5-3 leaf stage or at canopy closure (whichever occurs first).
- Graze down to consistent, clean residuals of 4 cm or 7-8 clicks on the RPM (approx. 1500 kg DM/ha).
- Keep repeating rules one and two. This allows light down into the base of the pasture, stimulating the production and survival of your daughter tillers. It also means high MS/ha production, as these same rules lead to high pasture utilisation, pasture ME and DM yield.
Nitrogen in late spring/early summer helps daughter tillers to grow up and establish quickly. It is important that by early summer most of these new tillers are fully grown with their own well established root system so that they can survive through summer. Nitrogen also helps new tillers better tolerate drought conditions, and reduces the incidence of rust in pasture.
These new tillers will be milked off for the remainder of the milking season. They’ll go through winter, vernalise, and produce their own daughter tillers before they in turn go to seed and die next spring.
Take care of your daughter tillers through spring and they’ll look after of you for the rest of their lives.