February Cropnotes 2015.
I recorded 63mm (2.5”) of rain in January.
To date winter rainfall is pretty close to average.
Wheat bulb fly egg hatch has only just started. Whilst the egg numbers are well down we can still expect to see damage in hotspot areas. Where Dursban egg hatch sprays are planned then remember to advise your spray operators to follow the latest guidance which requires all applications to be made using 3 star low drift nozzles and employing a 20m no spray buffer next to water.
Oilseed Rape: Pigeon deterrence will be the main job this month as flocks are just starting to target the crop. The end of the month will see the start in nitrogen application programmes. The first dose will usually contain the sulphur requirement for the crop, so there is little scope to vary the dose in response to canopy size and there is also little leeway for delaying applications.
NIABTAG trials have shown the most reliable way of assessing leaf area index in the spring is to carry out harvests of fresh weight in quadrat areas during February. The assessments must be made before the start of stem extension. Photographs of rape canopy can be uploaded to various web sites for estimates to be made, but be aware that results are more variable and good numbers of photos should be used to get a more reliable result.
Kerb and AstroKerb approval stops at the end of Jan, but Crawler can be applied until the end of Feb.
If conditions allow I will be targeting Fox and oil mixtures at areas of Charlock and other broadleaved weeds before the start of spring growth.
We are advised that light leaf spot levels will be high this year; crops will be inspected throughout this month for infection.
SRUC recently produced updated guidance for managing copper deficiency in cereals. Copper deficiency is more common in Scotland as a consequence of their more ancient soils.
In less severe deficiency situations, crops appear quite normal until ear emergence or even until harvest when the ears are not fully developed and are partially blind. Blind ears can also be a symptom of drought on sandy soils and does not necessarily indicate a Cu shortage. Sub-clinical deficiencies of Cu, where there is no appearance of visual symptoms, can reduce cereal yields. Fields with a history of poorer than average yields should be tested for extractable Cu.
Peas & Beans: Foot rot diseases of peas and beans are increased both by the frequency of legumes in the rotation and the poorer quality of the seedbed. Any restrictions to root exploration or drainage during the growing season will increase the risk of damaging attack. It has long been recognised that the primary cultivation should be carried out in dry soil conditions in order to produce a seed bed with the minimum of passes is key to growing a good crop of peas or beans.
Spring bean drills may start to roll this month. Seed rates should be calculated to establish 40plants/m2. This normally involves drilling about 45seeds/m2.
Drilling of dry harvest peas is generally best left until early March as February drillings often struggle to make the best yields. Target plant populations should be in the range: Marrowfats 65plants/m2, others 70plants/m2.
There may be some herbicide shortages in these crops as a consequence of the expected increase in acreage. Since we rely on effective pre-emergence products in both crops it will be worth getting stock on farm before the start of drilling.
Cross Compliance: The sustainable use directive is now in force and farms are required to demonstrate that Integrated Pest Management practices are followed. I think the easiest way to do this is to fill out the voluntary initiatives’ IPM. This can be done online at:
http://www.voluntaryinitiative.org.uk/en/vi-schemes/ipm-plans
Mike Thompson
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Home: 01760 755663