Around 200 people tuned in to Teagasc’s virtual crop walk on the last Thursday in May to discuss crop conditions around the country and the many untypical decisions that growers face in this very different year. These decisions hinge around the need for additional growth regulation (PGR) in lush crops in the south or the economic justification of most other inputs in drought-stricken crops in other parts of the country.
Advisers Michael McCarthy, John Pettit and Conor O’Callaghan reported on the state of crops across the south, southeast and northeast, respectively, and the challenges posed were then discussed by Steven Kildea, Shay Phelan and Michael Hennessy.
Oats appears to be the star crop to date, having fared best in terms of both establishment and early vigour
In general, oats appears to be the star crop to date, having fared best in terms of both establishment and early vigour to leave this crop looking well up and down the country. Spring wheat seems to be second best, helped by the fact that it was generally sown early when moisture was not limiting.
But the picture with spring barley was very variable, as reported in recent weeks. We saw pictures of crops from the south that left growers very concerned about lodging. There were also some pitiful pictures of late-sown ‘purple‘ spring barley crops, which were hammered due to inavailability of water and nutrients.
In the advice that followed, continuous emphasis was placed on crop risk and potential, in terms of being able to justify inputs at this stage.
Growth regulator
On oats, the two main questions posed were about fungicide on largely clean crops and growth regulation on crops between GS32 and GS37.
Given the lushness of oat crops in the south and southeast, it was suggested that a second growth regulator should be considered. While GS32 is the ideal timing for the first PGR spray, crops should not be under stress when PGRs are applied, especially when using trinexapac ethyl.
The feeling is that some crops in the south will need a second PGR. Variety must be considered – Barra has weaker straw. Applied N rate is also a consideration, given that we probably have more mineralised nitrogen in areas that got more rain.
Regarding lush spring barley crops, research has not found definite benefit from the use of PGRs
Product options are limited for late application – Medax Max is cleared up to GS41 and it is relatively soft on a crop. I have always found Ceraide to be soft and effective in such conditions and it can be applied up to GS39.
Regarding lush spring barley crops, research has not found definite benefit from the use of PGRs. The advice is not to use a PGR on this crop unless you feel you have no choice. Rapid growth often means that PGRs can be two to three weeks too late to be effective and only Medax and Terpal (and generics) are cleared for use late in the season.
Fungicide
There are bits of mildew and rust in spring wheat and oat crops in places but most barley is clean. However, rhyncho and net blotch are common in the south. So, can we consider altered spray timings and possibly push towards one rather than two fungicides?
Many early and vigorous spring barley crops have already received fungicide. When it comes to T2, these will need a contact product such as folpet plus a triazole and possibly a strobilurin or an SDHI. Again, the decision hinges around risk and return. Brown rust can come in late in dry years and must be watched.
If we don’t get rain, we may not get chocolate spot, but rain always comes, eventually
On later crops that remain very clean, there is the possibility to hold off on fungicide and opt for a single spray at GS39/49, unless there is a disease outbreak before that. But for crops that had only 50% establishment and are still suffering with the drought, any fungicide or further investment must be seriously considered and judged on the day.
Spring wheat and oat crops are good enough to carry two fungicides and while some crops are clean, one would need to know that there is no disease in the region before a decision is made to delay or skip a treatment. For now, the main emphasis is on mildew and rust control.
Beans and fungicide
With bean crops now coming into flower and generally free of disease, can fungicides be delayed beyond the start of flowering? There is some chocolate spot in crops in the south and some of these are already sprayed.
There are no definite answers to this question. If we don’t get rain, we may not get chocolate spot, but rain always comes, eventually. The critical thing is to have fungicide applied ahead of rain to protect it.
If the first fungicide was not applied in the drier areas, the advice was to skip the first chocolate spot application and one application should be sufficient.
Downy mildew was also mentioned. The feeling was that it is more dramatic looking than dramatic but it may need to be treated at times.
With clean crops and little prospect of rain, a single fungicide at GS39/49 may be an option on barley.Some heavy and lush crops of oats towards the south may need a second growth regulator. Crops that were badly hit by drought may not justify additional spend at this point.
Around 200 people tuned in to Teagasc’s virtual crop walk on the last Thursday in May to discuss crop conditions around the country and the many untypical decisions that growers face in this very different year. These decisions hinge around the need for additional growth regulation (PGR) in lush crops in the south or the economic justification of most other inputs in drought-stricken crops in other parts of the country.
Advisers Michael McCarthy, John Pettit and Conor O’Callaghan reported on the state of crops across the south, southeast and northeast, respectively, and the challenges posed were then discussed by Steven Kildea, Shay Phelan and Michael Hennessy.
Oats appears to be the star crop to date, having fared best in terms of both establishment and early vigour
In general, oats appears to be the star crop to date, having fared best in terms of both establishment and early vigour to leave this crop looking well up and down the country. Spring wheat seems to be second best, helped by the fact that it was generally sown early when moisture was not limiting.
But the picture with spring barley was very variable, as reported in recent weeks. We saw pictures of crops from the south that left growers very concerned about lodging. There were also some pitiful pictures of late-sown ‘purple‘ spring barley crops, which were hammered due to inavailability of water and nutrients.
In the advice that followed, continuous emphasis was placed on crop risk and potential, in terms of being able to justify inputs at this stage.
Growth regulator
On oats, the two main questions posed were about fungicide on largely clean crops and growth regulation on crops between GS32 and GS37.
Given the lushness of oat crops in the south and southeast, it was suggested that a second growth regulator should be considered. While GS32 is the ideal timing for the first PGR spray, crops should not be under stress when PGRs are applied, especially when using trinexapac ethyl.
The feeling is that some crops in the south will need a second PGR. Variety must be considered – Barra has weaker straw. Applied N rate is also a consideration, given that we probably have more mineralised nitrogen in areas that got more rain.
Regarding lush spring barley crops, research has not found definite benefit from the use of PGRs
Product options are limited for late application – Medax Max is cleared up to GS41 and it is relatively soft on a crop. I have always found Ceraide to be soft and effective in such conditions and it can be applied up to GS39.
Regarding lush spring barley crops, research has not found definite benefit from the use of PGRs. The advice is not to use a PGR on this crop unless you feel you have no choice. Rapid growth often means that PGRs can be two to three weeks too late to be effective and only Medax and Terpal (and generics) are cleared for use late in the season.
Fungicide
There are bits of mildew and rust in spring wheat and oat crops in places but most barley is clean. However, rhyncho and net blotch are common in the south. So, can we consider altered spray timings and possibly push towards one rather than two fungicides?
Many early and vigorous spring barley crops have already received fungicide. When it comes to T2, these will need a contact product such as folpet plus a triazole and possibly a strobilurin or an SDHI. Again, the decision hinges around risk and return. Brown rust can come in late in dry years and must be watched.
If we don’t get rain, we may not get chocolate spot, but rain always comes, eventually
On later crops that remain very clean, there is the possibility to hold off on fungicide and opt for a single spray at GS39/49, unless there is a disease outbreak before that. But for crops that had only 50% establishment and are still suffering with the drought, any fungicide or further investment must be seriously considered and judged on the day.
Spring wheat and oat crops are good enough to carry two fungicides and while some crops are clean, one would need to know that there is no disease in the region before a decision is made to delay or skip a treatment. For now, the main emphasis is on mildew and rust control.
Beans and fungicide
With bean crops now coming into flower and generally free of disease, can fungicides be delayed beyond the start of flowering? There is some chocolate spot in crops in the south and some of these are already sprayed.
There are no definite answers to this question. If we don’t get rain, we may not get chocolate spot, but rain always comes, eventually. The critical thing is to have fungicide applied ahead of rain to protect it.
If the first fungicide was not applied in the drier areas, the advice was to skip the first chocolate spot application and one application should be sufficient.
Downy mildew was also mentioned. The feeling was that it is more dramatic looking than dramatic but it may need to be treated at times.
With clean crops and little prospect of rain, a single fungicide at GS39/49 may be an option on barley.Some heavy and lush crops of oats towards the south may need a second growth regulator. Crops that were badly hit by drought may not justify additional spend at this point. 
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