Macalister Demonstration Farm Update 478
(Week ending 31st August, 2018)
More than half of the herd has now calved so the season is getting into full swing. The calculated pasture consumption is 32 Kg DM/ha/ day, which is a jump up on the last period’s 23
kg DM/ha/ day. The grass is excellent quality, very leafy, and no sign of rising seed heads. Some paddocks have excellent soil moisture, some quite dry. Irrigation has just started for the season.
The next break to be grazed is recently re-sown annual ryegrass. It has a huge quantity of 2,800 kg DM/ha a d has been rested 52 days, with 2.8 leaves regrown. That is a leaf appearance rate of 19 days which is typical for late August. The grass in this paddock is enjoying the release of nutrient from organic matter when the soil was stirred up at sowing.
In contrast, the paddock after that to be grazed is older perennial ryegrass. It has an available quantity of 1,000 kg DM per hectare, 2.5 leaves, 48 days rested. The poorly grown patches in this paddock are suffering from being grazed short (3 cm height) at the previous grazing. Whilst grazing residue is commonly measured in Kg DM/ha, measuring the quantity of residue is inaccurate, especially using a plate meter, because it picks up bumps and holes in the ground, making the figure meaningless. Residue is best assessed as the “plant’s height” because plant height governs its ability to re-grow fast. We should be aiming for 6 cm residue between the clumps to maximise growth.
