The dwindling arsenal of active ingredients and increasing pressure from resistant grasses are forcing growers and contractors to reconsider mechanical methods of control.
Once the preserve of the organic and specialty crop sectors, camera-guided weeders are becoming an increasingly attractive option for those looking to reduce their reliance on chemicals.
See also: How remote sensing technology can help refine grass management
These versatile tools are available in modular formats, which means they can be adapted to almost any crop planted in rows. For example, a machine may be suitable for hoeing maize at 75cm, sugar beet at 50cm and cereals at 25cm, some up to 12.5cm.
Highly accurate camera guidance systems work in tandem with a sideshift mechanism to keep the weeders in line, allowing them to work within those tolerances without risking crop damage. If the conditions are right, they can drive at speeds of 12 km/h or more.
To show off their capabilities, the Norfolk Agricultural Machinery Club (Normac) held a demonstration event on a maize crop supplied by Raynham Farm Company, near Fakenham. This was drilled at a conventional 75cm spacing, and most makers came armed with an 8 eight-row/6m machine.
Monosem’s Multicrop hoe uses a single or dual camera guidance configuration from Tillet and Hague, and is available in several configurations up to 18 rows by 9m, or 12 rows at 75cm spacings.
Monosem says he gave the Multicrop a sturdy construction to withstand heavy arable use, and it rolls on large diameter 350x120mm depth control wheels.
Each grow unit is supported by a long parallel linkage and has a simple T-bar depth adjuster that can be moved in 5mm increments.
The Multicrop comes with an integrated sideshift frame with four ground engaging discs on the side of the tractor to help keep it stable. There is also an option to have a separate side-shift frame that can be used with other implements, which is the stock configuration for larger machines.
For the maize demonstration, UK importer Toucan Farm Machinery purchased a 6m eight-row machine with integrated side-shift frame and row units configured with five spring tines and rotating crop guards. These prevent soil from being thrown over young crops, but can be removed from the crop when the plants are more mature.
The machine also featured spring-loaded down pressure adjustment and Isobus hydraulic section control that lifts each unit independently on inclined headlands. It also had a distributor head for applying fertilizer.
Prices vary widely depending on spec, with the fully loaded model pictured being around £80,000.
Inter-row cultivator Edwards Farm Machinery
Originating in Worcestershire, Edwards Farm Machinery builds and imports machinery suitable for agricultural and horticultural use.
The inter-row cultivator is one of its in-house products, available in working widths of up to 12m and with the option of multiple row spacings, up to 12.5cm.
In its standard form, it has a side-shift frame built into the headstock, with a pair of discs used to arrest movement on the tractor side of the frame. However, it can also be used as a stand-alone hoe, paired with one of its side-shifting frames.
Each hoe unit mounts to the frame via parallel linkage and comes in a myriad of configurations to suit different crops.
Multiple tine, paw, and crop guard options are available, and the design allows for easy interchange and spacing changes. Buyers can also add finger weeders to eliminate weeds along the crop row.
Guidance is provided by a dual Tillet and Hague camera system to ensure accuracy when working on sloping headlands. A 6m eight-row machine with hydraulically folding frame costs around £33,000, including twin guide cameras.
For more aggressive weeding, Edwards Farm Machinery offers an inter-row rototiller built by Comeb. It is available in working widths of up to 6m and the option of different milling heads from 14cm to 76cm wide.
British importer Keith Rennie Machinery was demonstrating French company Carre’s Econet hoe, which is available on different frames and can be configured with 6 to 18 rows.
The spacing can be adjusted by loosening a clamp and sliding the hoe units along the main beam, to a minimum of 18cm.
Pictured is the 6m mounted option with eight hoe units set at 75cm, each mounted on a parallel linkage with a manual reel to adjust the working depth.
This machine has been configured with five spring tines and rotating crop guards that can be removed from the job as the crop matures. However, Carré offers several configurations to adapt to different row widths and floor types.
Guidance is provided by a single or dual version of Claas’ Culti Cam system, which uses a touch screen. This triggers the built-in sideshift mechanism to bring the tool online.
Optional extras include Isobus section control, star finger weeders and fertilizer kits. Retail price of the 8 row machine shown is around £45,500 with optional section control adding around £10,500.
Transformer Horsch VF
Horsch is a recent entrant to the mechanical weeding game, launching his Transformer VF camera-guided hoe in 2019.
Four frame sizes are available – 6m, 9m, 12m and 18m – with all but the 6m folding into five sections.
Each has an integrated sideshift mechanism controlled by a single or twin Claas Culti Cam system, with discs on the tractor side to hold the chassis in place. Different combinations of hoeing units can be added to these, allowing a range of row spacings from 25 to 80 cm.
The individual hoe units are mounted on a parallel linkage, with a tool-less adjustable front depth wheel.
Additional options include spring or hydraulic downforce to help keep units on the ground and section control so units raise and lower independently on headlands.
The implement shown sits on a 6m folding frame and is set up for hoeing between established grain crops with a Horsch Avatar set to 25cm rows.
It is also fitted with an optional rear following harrow which can be adjusted to give a more even finish between rows, or placed on the row to work between plants.
Illustrated indicative price is approximately £62,000.
Steketee EC weeder
Steketee has been owned by Lemken since 2018 and its range of weed control equipment is now available for purchase through the company’s established dealer network.
The EC-Weeder is its camera-guided hoe, available in working widths of up to 17m and multiple row spacings down to a minimum of 15cm.
Unlike most other side-shift hoes, Steketee uses a horizontal linkage to move the tool from side to side, rather than dragging it along a bar. The company says this means less force is needed to move it into position, which means the front part of the frame can run on wheels, rather than discs in contact with the ground.
This steering mechanism is also available as a separate unit, called EC-Steer, which has a three-point hitch to which conventional hoes can be attached.
Guidance is provided by Steketee’s own IC-Light camera system, which recognizes the crop from its color and guides the hoe within 2cm of it, even when working at speeds of up to 15 km/h.
Several combinations of hoeing tools are available to suit different crop types, including the three tine per row configuration shown, with rotating crop guards and additional finger weeders. It is also available with Isobus section control.
Guide price for the 6m eight row machine pictured is around £75,000.
Garford has been building camera-guided hoes equipped with Tillet and Hague camera guidance for over 20 years.
It has options for weeding between crop rows and between plants along the row, although the latter can only really be justified for high value crops.
Robocrop is the company’s cross-row offering, which is configured with a separate steering head, to which the stationary hoe attaches. This gives it the flexibility to be used with other tools.
The guidance system analyzes the crop images at a rate of 30 frames/sec, which allows it to work at speeds of 12 km/h.
Models are available from 1m to 18m in a mounted folding frame and there is even a trailed 24m option. A wide range of tines, coulters, blades and crop guards can be attached to these to suit the job at hand.
Each hoe unit is mounted on a parallel linkage and has an adjustable frame on which the cultivation elements can be arranged in different formations. These run on a front depth wheel, with a removable handle to adjust the height.
Additional options include a vacuum system to keep the implement on the ground and Isobus section control. Unlike competing machines, this only raises the tines, leaving the depth wheels in place.
The eight row 6m machine on offer costs around £52,000 with section control tine lifters.
Robust Smart Cultivator
A new smart cultivator from US company Stout Industrial Technology aims to solve the problem of labor shortages in the fresh produce sector by offering precision weeding of high-value crops such as lettuce.
The trailed implement is equipped with an artificial intelligence (AI) system that identifies the precise locations of crops and weeds, before using ultra-precise weeding arms to dislodge any weeds.
It can do this through a series of high-definition cameras that scan the terrain and send images to the AI’s brain (or neural network, to use the appropriate term), where they’re analyzed.
The company says setup is simple, with a touchscreen on the machine where users enter crop type, plant spacing, row spacing and machine size. Once these simple settings are added, it can be moved up a row and left to fend for itself.
It is designed to work in beds from 1.8 to 2 m and can cover up to eight rows in one pass, at speeds of up to 2.5 km/h.
Stout machines are imported by UK Planter Solutions and so far there is only one demonstration machine in the UK. Prices are yet to be announced.