Don’t miss out on a potential €13,500 additional milk revenue

Year to date our average cow has produced c.4000 ltrs of milk.  There is a lot of valuable milk yet to flow.  With a 3 % weekly decline from here to drying (based on 65c/ltr milk value) our average cow will produce €1080 from here to drying off.  With a 1.5 % weekly decline from here to drying (based on 65c/ltr milk value) our average cow will produce €1215.  That’s €13,500 additional milk revenue from here to drying off by maintaining milk volume as high as possibly for a s long as possible.

Milk Revenue from the average cow from here to Drying off from a controlled decline vs an accelerated Yield decline:

For the next month we need to feed our cows adequately, maintaining yield and holding milk protein % as high as possible for as long as possible while building grass covers.

To maintain production, intake must be maximized; grass quality must be maintained and a balanced amount of concentrates must be fed.

How do we maximise milk yield and milk protein from here to year end?

1. Maximise your cows’ intakes of good quality grass across the autumn by spreading fertiliser now to build a wedge of grass to carry you through

Final N fertilizer application of the year

The aim of the final N fertilizer application of the year is boost grass growth in order to build grass covers for the Autumn. Many farmers are completing their final blanket spread of N in the last week of August/ first week of September compared to waiting unit the deadline day of the 14^th September. By doing this they are taking advantage of the superior growth rates now compared to mid-September and getting a greater return from the final blanket spread of N fertilizer. Recent Teagasc trials clearly demonstrates that delaying the final N fertilizer application in autumn significantly reduces the grass dry matter yield response to fertilizer N (Figure 1).

The units N/acre applied will vary across farms and should be decided upon based on the remaining fertilizer N allowance of the farm for the year and on the amount of grass on the farm at that time. If rotation length and average farm cover is on target or ahead of target an application of 20-25 units will be sufficient.  However, if rotation length and average farm grass cover is behind target an application of 30-35 units/acre should be applied.

Figure 1: Recent Teagasc trial results illustrating the grass dry matter yield response to N fertilizer applications at three different timing in the Autumn. Source David Wall and Ian Fox, Teagasc Johnstown Castle.

Maintenance P and K

Figure 1. Maintenance P and K requirements for a grass cover of 1,500 kg DM/ha depending on weather it is grazed or cut for bales.

The maintenance P and K requirements of a paddock in any given year will depend on the yield of the paddock and weather the paddock was primarily grazed or if there were, surplus bales cut on the paddock. Figure 1 highlights the amount of P and K removed from a cover of 1,500 grass DM/ha. Up to 10 times more K can be removed from a paddock when it is cut for bales v’s grazing. When grazed cows will recycle 90% of the K in the grass back on to the paddock in dung and urine. If baled 100% of the K in the grass is removed from the field. A typical bale of silage contains 10 units of K and 1.7 units of P.

For example if a paddock was grazed 6 times so far this year and will be grazed another three times before the end of the year the maintenance requirements can be worked out roughly as follows:

9 grazing x 3 units K/grazing = 27 units K/acre

9 grazing x 1.7 units P/grazing = 15.3 units P/acre

This changes significantly, where surplus bales are taken. For example if the same paddock was grazed 8 times in the year and cut for surplus bales once at a yield of 4 bales/acre the maintenance requirements for K are as follows:

8 grazing x 3 units K/grazing = 24 units K/acre

4 bales/acre x 10 units K/bale = 40 units K/acre

Total = 64 units K/acre

These figures can be used to work out the K and P maintenance requirements of your individual paddocks. An application of 2,000 gallons of slurry will provide anywhere from 40 to 65 units K/acre and 8 to 12 units P/acre. Using slurry is the cheapest ways to meet these P and K maintenance requirements but often there is not enough slurry to go around the entire farm. Now is a good time of the year to assess what has been applied P and K wise year to date and determine if sufficient P and K has been applied via slurry or fertiliser to meet P and K maintenance requirements.

Fertiliser actions for September

• Review soil samples for lime status and apply lime as required
• Assess P and K maintenance requirements
• Apply slurry first and then fertiliser to meet P and K maintenance requirements
• Apply final N and P fertiliser applications before the 15^th September

2. Maintain cow intake at all time. Your cow will eat grass and concentrates and may require silage depending on your growth rates and your stocking rates. Concentrates are better to maintain production as they contain more energy on a kilo basis than grass silage (its energy or UFLs not where they come from that drives production).  4kg DM of concentrates contain c.4 UFL, 4 kgs DM of grass silage depending on quality may contain 2.8-3.2 UFLs.  But a kilo of grass silage is better than a kilo of air.  Ensure your cows are full every day.  Do not sacrifice cow intake to build a wedge of grass.

Building grass across the month of September

Grass Growth in August was poor, a lot of farms now find themselves behind target for grass as we start the month of September.  We need to build grass covers now before growth slows in mid to late September.  If your farm is behind target more concentrates will be needed to allow you to build this cover of grass.

Grass Growth needed to meet demand (0 cover built)

Concentrate Feeding Required to be on target for grass on the 1st October based on current grass levels