Tillage: Preventing manganese deficiency in winter barley crops a priority
Preventing winter barley crops from succumbing to the threat of manganese deficiency is now a field work priority.
The point was discussed at a recent meeting for tillage farmers, hosted by Teagasc in Burt, Co. Donegal.
Driving the manganese issue has been the impact of the incessant rain on soils over recent weeks.
Teagasc tillage specialist, Shay Phelan, commented: “It‘s important for all growers across the country to get a manganese spray on to their crops as soon as ground conditions allow.
“For the most part, winter barley crops have continued to progress well over recent weeks, with tiller numbers at acceptable levels.”
Prior to the meeting, Teagasc advisers had walked a selection of winter barley crops with a selection of plant samples brought to the meeting for discussion purposes.
Phelan said: “Plants seem to be tillering well, with shoot numbers in the region of five to six.
“Tiller numbers are the key determinants of final yield in winter barley crops.
“This means that final crop performance is laid down at quite an early stage of crop development. This is somewhat in contrast to wheat.”
More generally, Teagasc is reporting that early drilled winter barley crops in the south are advanced with an extra tiller on many plants.
The target plant count for two row varieties is 1,100-1,200 shoots per square metre, in order to maximise final yield.
Some crops did not receive an autumn herbicide. Unfortunately, there is no reliable control over annual meadow grass from the spring application of a herbicide.
With regard to the application of fertiliser nitrogen on winter barley crops, the perceived wisdom is not to rush out with the spreader just yet.
“If crops are looking healthy, then the need for significant applications of nitrogen at this stage is not apparent,” Phelan commented.
“Plant uptakes will be low with the result that most of the nitrogen applied will either be lost through leaching or volatilisation to the atmosphere.
“One exception to this rule might be crops of early maturing varieties, such as Joyau. They are probably more advanced at this stage and could be benefit from a nitrogen application.”
The Teagasc specialist highlighted that barley crops "need nitrogen most in the run-up to stem extension".
"In the case of winter crops, this generally takes place during the period late March through to early April.
“Growers should target for nitrogen applications from mid-tillering but before Growth Stage 30.
“Potash and phosphate must be applied in line with a valid soil test result.”
