Mechanical weed control in sugar beet is nothing new, but traditional hoeing practice was slow, uncomfortable and an unpopular task.

But with diminishing herbicide options and a new generation of camera-guided hoes on the market, Morley Farms joined forces with Lemken and local New Holland dealer Ernest Doe to evaluate the Steketee hoe in 2020 and 2021.

Based in Norfolk, Morley Farms is run by the Morley Agricultural Foundation, a charity which funds and supports agricultural research and education working with several research organisations including NIAB, British Beet Research Organisation (BBRO), the John Innes Centre and Agrovista.

As well as 30 hectares of plot trials, Morley Farms has a 700ha commercial farm which helps to fund future research.

Farm manager David Jones says: We could see that with modern tractors and steered hoes, we could achieve higher work rates and it would be a more comfortable operation.

Theres also the potential to tackle more difficult weeds, such as black-grass, ryegrass, knot-grass or thistles.

Most farms have troublesome weeds of some kind, so a hoe might be a useful tool for sugar beet or other wide drilled crops.

Specialist Lemken, which acquired Dutch weeding technology specialist Steketee in 2018, supplied a six-metre 12-row EC-Weeder.

This uses the IC-light camera system to detect the rows, processing the images to guide the hoeing elements between them as close as 2cm from the crop, to pull weeds out by their roots.

It was powered by a 130hp New Holland T6 on narrow wheels, with the EC-Weeder terminal in the cab displaying the hoeing path.

The outfit was used to hoe selected 24m tramlines and in 2020s variable crop, to target specific weed patches or different soils and conditions to assess its effectiveness for subsequent discussion between the parties, which also included BBRO.

The group was able to consider what would work and what we would change, says Mr Jones.

We realised that while the camera system was effective at steering the hoe and accurate in working between the plants, it takes quite a bit of setting up for different sizes of plant and if they vary in the field, has to be adjusted to hoe them accurately.

While the cameras can pick up the shape and colour of the sugar beet plant, if you do go wrong its easy to take out several rows of beet before the operator realises.

You can also easily run beet down at the end of the row.

Timing is also key as there is a limit to the size of crop that can be hoed it is only possible until the rows meet.

But equally its hard to set a specific date for hoeing because the conditions have to be right, adds Mr Jones.

If the hoe is used in the wet, the narrow wheels on the tractor can cause damage.

In addition, the weeds that are pulled out will simply regenerate.

Ideally, hoeing should take place on a hot, sunny day so the exposed weed roots die.

Choice of tractor and wheels is also important to avoid sinking into softer soils and as the weeder sits out behind the tractor, any unit wider than the 6m version trialled would have been too heavy for the tractor used.

There are limitations to hoeing compared to spraying, Mr Jones says, including lower work rates from a narrower implement.

Hoes also only take out the weeds between the rows, whereas a sprayer will also tackle weeds in the row.

Growing conditions have to be taken into consideration hoes work best on smooth seedbeds, but sugar beet is often grown in stony, rough conditions which can make the tine jump out.

Consistency BBRO crop mechanisation development specialist Stephen Aldis says: The basics are more important than ever if you are looking to hoe successfully, as it needs a good, level seedbed and consistency of planting.

Mr Jones suggests that while the benefits are clearer for high value crops such as vegetables, its a large investment for sugar beet.

But there is potential for development, now we have the ability to guide the implement with such accuracy.

It could be effectively used for a combined hoe and spray operation, or with hoeing combined with other methods of weed control such as electrical destruction.

Mr Aldis suggests it could also be successfully combined with side injection of fertiliser, reducing overall applications and boosting accuracy.

He adds that as a standalone pass, growers also need to think about the operator costs for a more labour-intensive operation than spraying.

Many growers use contractors, so they need to consider whether hoeing would fit into their range of services or whether its something that would be brought in-house.

Being able to cover the acreage could be a challenge.

Its not going to suit everyone, says Mr Aldis.

Unlike vegetable crops, sugar beet is grown on a variety of soil types and by growers with different resources, while the variation in seasons will also affect how well it works.

Use on multiple crops also shows promise, says Mr Jones.

We have tried it in maize, although the disturbance could encourage ryegrass to germinate.

But in this crop again, hoeing could be a good way of tackling difficult weeds.

With so little modern on-farm experience of hoeing in conventional systems, part of the plan for the trials was to host demonstrations for and discussions with farmers, although this was sadly curtailed by Covid-19.

Technique We would consider hosting an open day or similar for the technique in 2022, says Mr Jones.

There are so many variables with sugar beet and where herbicides are working it is currently simpler and cheaper to spray.

But if they become less effective or are removed from the market we would certainly have to consider other techniques.