Late October and early November is an ideal time to walk crops to assess establishment rates and the effectiveness of weed control.

Following an excellent spell of autumn weather, most winter cereals were drilled in ideal conditions from the end of September through to mid-October.

According to agronomists, establishment has generally been excellent across the country.

The favourable conditions also led to a notable increase in the use of pre-emergence herbicides this season, a very positive step for effective weed control, particularly in controlling troublesome grass weeds.

Precision technology

Tillage farmers continue to lead the way in the use of precision technology, particularly when it comes to drilling.

This has resulted in highly accurate bout widths and perfectly straight tramlines across the country.

Meanwhile, drill calibration has become much easier, and the inclusion of the thousand grain weight on seed bags from seed companies now allows farmers to fine tune seeding rates with even greater accuracy.

The final piece of the jigsaw is measuring the number of plants that have established. This provides valuable information for future seed rate calculations.

While an establishment rate of 85% is often assumed, it can vary significantly between fields and seasons.

By calculating the actual establishment rate, farmers can make more accurate adjustments to drilling rates in the future.

Plant counts

Experienced farmers and agronomists can usually make a good visual assessment, but taking actual counts gives more precise information on plant populations.

This information not only helps finetune future seed rates but also serves as a valuable management tool later in the crop’s development.

Measuring plant counts can be done in a few simple ways.

One common method is to use a quadrant, for example 0.1 m², and multiply the number of plants counted by 10 to get plants per square metre.

Alternatively, a circular pipe with a circumference of 158cm gives an area of 0.2m², in this case, multiply the count by five to calculate plants per square metre.

Another option is to use a ‘1m’ stick/tape, count the number of plants in a row over 1m, then count how many rows fit into 1m across the drill width, and multiply the two numbers together to get plants per square metre.

Weed control

The increase in pre-emergence herbicide use in both winter wheat and winter barley this year has been facilitated by the good weather at drilling.

This trend also reflects a growing awareness of the threat posed by grass weeds in these crops.

In some fields, slight phytotoxic (herbicide) effects are visible, typically as leaf whitening or bleaching.

This is normal and crops usually recover within a few days. The symptoms are most noticeable on overlaps and headlands.

For crops that have yet to receive a herbicide treatment, it is important to target pre- or early post-emergence applications as soon as possible.

Early control of weeds, especially grass weeds, is far more effective when weeds are small.

Delaying control until the spring has led to increasing challenges in recent years particularly with brome species and annual meadow grass.