Action needed to address grass surplus

All Dairylink Ireland participants have received rain and a lift in temperatures, which has accelerated grass over the past 10 days on most farms. Buffer feeding has now stopped and the grass deficit from a few weeks ago has quickly turned into a surplus for some farmers.

Programme participants measure grass covers at least once a week and base management decisions on the grass wedge that is produced by software programmes such as AgriNet.

However, for dairy farmers who do not measure covers, regular walking and visual assessment of grazing blocks are still essential, especially at present, when grass availability is changing rapidly.

As a first step, Dairylink adviser Aidan Cushnahan suggests non-measuring farmers should look at the covers that cows will be grazing in seven to 10 days’ time.

“If the grass looks suitable for grazing now, then it will be too strong by the time cows get round to grazing it. This surplus should be taken out for bales now,” Aidan said.

Farmers should avoid the urge to delay mowing surplus paddocks to allow covers to bulk up for a better crop of bales. Doing this will only increase the length of time that these paddocks are out of the rotation. It will mean the grazing round is too short and stocking rate too high for a prolonged period, which could lead to a grass shortage.

Dairylink farmers are also being encouraged to keep a close eye on post-grazing covers and top paddocks after cows if need be, to help maintain sward quality in subsequent grazing rounds.

We got rain at different stages over the past fortnight and it has warmed up, which has helped push on growth

With grass growth now running ahead of demand, there may be a temptation to miss a round of fertiliser in some paddocks. However, this is not recommended at this stage in the season, as it will reduce both the quality and quantity of grass later in the year.

Grass growth has picked up considerably on James King’s farm near Ballymena over the last two weeks.

“We got rain at different stages over the past fortnight and it has warmed up, which has helped push on growth. Conditions have been ideal for grazing so far this year,” James said.

The latest grass walk on Tuesday showed that growth is sitting at 89kg DM/ha/day, up from 50kg DM/ha/day the week before.

Average farm cover is 1,088kg DM/ha and the milking platform stocking rate is 5.13 LU/ha.

Almost 6ha of surplus grass will be taken out for bales

In terms of cover per livestock unit, the current figure on the King farm is 212kg DM/LU. This is ahead of the mid-season target of 160kg to 180kg DM/LU.

It means James has a grazing surplus, so some excess grass will need to be taken out to reduce his cover per livestock unit figure and bring supply in line with demand on the grass wedge chart.

Almost 6ha of surplus grass will be taken out for bales.

This will take average farm cover down to 860kg DM/ha and put cover per livestock unit back on target at 170kg DM/LU.

Buffer feed

Cows were getting a buffer feed of fourth-cut silage and 2kg/head/day of blend during the dry period, but this has now been cut out and all concentrates are being fed through in parlour feeders.

James is now on his fourth round of the milking platform this season and has noticed cows are not cleaning paddocks out as well as they had been.

Fertiliser is spread on the milking platform after grazing

He is topping after cows with a mower to bring residuals down to the ideal post-grazing cover of 1,500kgDM/ha.

Fertiliser is spread on the milking platform after grazing. The product used depends on soil analysis results from last winter, but is generally either CAN or a compound fertiliser, such as 27:4:4, spread at a bag per acre.

Butterfat rise

Butterfat levels reduced on the King farm from 4.19% in mid-April to 3.60% a fortnight ago. It has since started to move upwards and is currently sitting at 3.91%.

If butterfat levels are an issue, it is also worth reviewing the composition of parlour nuts

The drop, and subsequent rise, is being put down to cows grazing low covers when grass availability was tight over the past few weeks. This likely led to a lower fibre intake, which supressed milk butterfat.

If butterfat levels are an issue, it is also worth reviewing the composition of parlour nuts, to ensure there is adequate fibre source in the ingredients list, such as soya hulls.

Silage

First-cut silage on the King farm was mowed on 11 May and ensiled the day after. Despite looking like a lighter crop before mowing, James said that it turned out to be a similar bulk to last year, although it is drier and should make better quality winter feed.

Slurry went on to the silage ground later that week at 3,000 gallons per acre and fertiliser was spread the following week.

“Regrowths were a bit slow at the start, but grass has started to come on over the past week. We should be ready to cut again in four weeks’ time,” James said.

Read more

Dairylink: a beginner’s guide to budgeting grass

Dairylink: making silage four times a year