Agronomy Update - November 2020

Jonny Oosthuizen - Bartholomews Agronomist

What a difference a year makes! In many cases, growers have acted on lessons learned from last year and drilled earlier than usual in order to attempt to ‘guarantee’ an acreage of winter cereals for harvest 2021. Acting on hindsight, however, has its downfalls as mentioned in previous articles. Many growers have kept on top of the potential issues and in most cases have applied herbicides/insecticides proportionally to their situation.

In some cases, the bias towards drilling has meant that the rain has arrived before the roll was let out the shed and thus seedbed quality has been limited. On top of residual herbicides being most effective on soils with a fine, firm tilth, rolling also serves as a strong branch of our IPM strategy for the reduction of certain pests including slugs and wireworm which have both been an issue this autumn.

Oilseed rape crops are progressing with the CSFB damage being significantly less severe than last year. Growers attention is now being turned to clarifying their commitment to the protection of these crops, now they’ve got through this first stage, which was unexpected by some. There are a number of potential herbicide products covering numerous uses, but careful attention needs to be focused on the stewardship surrounding the use of these in relation to the surrounding environment. Phoma is also appearing in a number of places and may need targeting if thresholds are met.

Currently the most time sensitive aspects to consider in cereal crops are black-grass control and aphid populations. In many cases, growers will be looking at further contact control for grassweeds following pre-ems. Product choice will depend on the population and resistance profile but remember only one application of an ALS-inhibitor can be applied for grassweed control.

In relation to aphids, they have been very active in many cereal crops across the south and an insecticide has often been used with the herbicide where application has been delayed due to weather. Using the ‘BYDV Assist’ app by Syngenta, you can determine if and when any further insecticide applications are required for your local area. Crops drilled later will be emerging in November and thus are unlikely to require an insecticide, provided the weather isn’t too mild of course.

There seems to have been more issues this year with frit-fly damage where fields have been turned around quicker than usual in order to make the most of the weather windows and get crops drilled. This along with continued uptake of low disturbance drilling/cultivations (a good thing in relation to soil health) serves to remind us that when working with mother nature, there’s a continual balance to be struck.

Once again, continued innovation and adoption of new technologies and fresh thought-processes should be considered regularly and where efficiencies can be employed, they should be tailored to fit your business.