West: Good weather brings drying times
What a difference two dry weeks make! Soil surfaces are now drying such that some shallow cracks have developed and any standing water has mostly receded to reveal the extent of plant losses to water logging. Decisions now can be made on what to do with the patches lost, although the soil always goes down a bit sad after being in anaerobic conditions for that length of time. The drier conditions have allowed us to get first split of N:S fertiliser applied on most crops.
Early September-sown wheat on lighter, warmer soils are easily at GS30 with leaf unrolling, revealing that eventual leaf 4 is 20-50% emerged and with a phyllochron (leaf emergence) of 130-150 day degrees I expect these crops to be at T1 fungicide timing 7-10 days earlier than my 23 April St. Georges day rule of thumb.
On these forward crops T0s were applied last week, consisting of first half of plant growth regulator’s (Chlormequat + Moddus) as these crops are strong with a high lodging risk. Chlorothalonil is the building block for septoria control at T0 for me, with a low rate of triazole (tebuconazole or cyproconazole) added in depending on variety. although apart from Oakley I have not found the yellow rust widely reported further east and south. Autumn residuals have worked well in most situations, although the bromes have come through them, as is often the case, so Broadway Star has been included in these situations.
Later September and October drilled crops will have T0 in the coming week with Othello included for annual meadow grass and broad-leaved weed control where no residuals were applied before the rains in the autumn.
Hopefully the recent fertiliser applied to winter barley will start to change the rather yellow looking crops to a greener hue. All of the crops are very well tillered, so again are having a first split of PGR along with an inexpensive fungicide where mildew, rhynchosporium and brown rust can be found.
Oilseed rape is rapidly approaching flowering with crops ranging from green to yellow bud with DK Extrovert, Harper and Cracker being the most forward. The latter being grown on farms where clubroot is known to be a problem, this season is turning out to be a bad year for the disease – a consequence of the open autumn – and patches are now starting to show up on farm. The semi-dwarf varieties such as Troy and PX109 are more uneven, with much more variable plant height than I have seen previously which is possibly a function of the lack of a winter.
Light leaf spot has been slow to develop, but is now becoming obvious so prothioconazole will be added to the tebuconazole to hold back the larger crops. I have only found low levels of pollen beetle (4-6/plant) in forward crops, these will have produced in excess of 50% buds needed for optimum yield and a colder forecast for next week means I cannot see any justification for inclusion of insecticide.
T1 decisions and choices are now uppermost in the mind for the next few weeks and ‘trade’ talk of supply shortages in one of the key azoles is complicating the independent decision process. The cynic in me says this maybe an attempt at influencing the market so perversely, in a way, I hope it is a genuine supply issue that we have to work around.
On farm field work is now the priority so let’s hope the weather helps to get things completed on time which always helps the health and temperament for both agronomist and farmer.