Farm Ireland

Friday 23 February 2018

Great weather will help crops power through growth stages

Michael Hennessy
Michael Hennessy

Michael Hennessy

For the most part those who were considering not planting this year have succumbed to the glorious weather and it appears almost all tillage land will be sown again.

Crops sown over the last week or so should be through the ground relatively quickly and, all going well, will power through the growth stages without a hitch.

Last week, as part of the ongoing Teagasc spring crop walks, I visited some farms in the south east. The first farm had a crop of advanced Cordial winter wheat which was sown after beans on October 14.

This crop was at a strong first node and was likely to reach the second node by early this week. The crop had received its first split of nitrogen and the second split was applied over the weekend. The application of a growth regulator was a priority for this crop and again it should have received it over the weekend.

In terms of the correct choice of growth regulator, the grower had a choice but time was not on his side. Although the crop was unlikely to have reached terminal spiklet (the latest growth stage where the application of CCC could inflict damage) an alternative growth regulator to straight CCC should be considered.

Products such as Meteor (2.0-2.5l/ha) or Canopy (1.2-1.5l/ha) have label clearance to be applied to a crop up GS32. Canopy can be applied up to flag leaf. Straight CCC products are restricted up to GS31.

The crop had septoria on its older leafs but no active lesions were present. The next job was to split a plant to see the position of the leaves. It revealed that the fourth last leaf was half way out and the third last leaf was unlikely to appear for about seven to 10 days. As Cordial is not the cleanest variety, chlorothalonil 1.0l/ha (Bravo) would be added with the growth regulator and the first main fungicide would be planned for the last week of April.

On the same farm, Sparrow spring wheat, sown in mid February, was at the three-leaf stage and a good scattering of weeds were present. Paring back to soil revealed plenty of weeds yet to emerge and the slight cap on the surface was probably holding back this emergence a little. It is planned to apply a herbicide like Ally Max (half rate) plus CMPP to the crop towards the end of this week. The rate of the herbicide will be dictated in part by the growing conditions in the days leading up to the application.

Also Read

Cold and harsh weather will necessitate increasing rates, where as warm, dull growthy time is ideal for reducing rates. An aphicide will not be applied to the crop as the advice this year is that it is not necessary to crops sown up to last week due to the very low aphid numbers. The crop has received all its P and K and has received 63kg/ha (50 units/ac) of nitrogen. The crop will not receive further nitrogen for about two weeks.

An early April sown crop of Sebastian spring barley was at the two leaf stage. The crop was sown at 147kg/ha (9.3 st/ac) which has resulted in a plant stand of 270 plants per square metre or about a 90pc establishment rate.

The crop has received 63 kg/ha (50 units/ac) of nitrogen and all its P and K in the form of 18:6:12. It is planned to top up the nitrogen around early tillering. Concern was expressed about the levels of grain protein produced in previous years on the farm and the ability to of the grain to achieve the required making standard this year.

Minch Norton want a minimum spec of 9.3pc grain protein (range 9.3-11.6pc). Over the past couple of years quite a large tonnage of barley failed to achieve the minimum protein levels. However, average grain proteins (9.5pc) delivered up to then were on the lower side of the scale but did make this spec.

Season has a large part to play in how nitrogen is taken up by the plant and subsequently converted into protein. In the past, an early application (before early tillering) of nitrogen was preferred to minimise protein levels and maintain yield. This timing protects yields by supplying adequate nitrogen so that the plant produces. This practice should not change.

The winter of 2009 has many similarities to 2008 in that both were very wet leaving very little residual nitrogen in the soils. Growers should continue to apply all the nitrogen (index 1, 135kg/ha N) to the crop before mid tillering. Where a grower has additional nitrogen (as part of the Nitrogen Directive) then this should be applied no later than GS30. An option of applying a liquid feed is available later in the season, if necessary, but nitrogen in these products are counted as part of the total nitrogen for the Nitrates Directive.

Irish Independent