Two-pass strategy ensures best start for oilseed rape

A two-pass strategy is giving early drilled oilseed rape the best opportunity to grow away from pests on a Staffordshire farm.

The approach is saving time, fuel and labour – and improving soil health, says Staffordshire farmer David Roberts, of DS Roberts and Son. It follows the purchase of a Multicast Duo and Multicast 200 applicators to establish the crop.

The strategy has resulted in higher rape yields. It involves the simultaneous application of a companion crop and slug pellets with direct drilled rapeseed into stubble – with good results and minimal soil disturbance.

Mr Roberts runs the 400ha fourth-generation family farm near Tamworth in partnership with his father Denis. Two seasonal staff are employed to share the workload at busier times of the year.

Establishing high-yielding winter crops is a key goal. “Our current rotation is two wheats followed by oilseed rape, which although agronomically challenging, is still the most profitable rotation for the business.

Applicators

Up until 2021 Mr Roberts still employed a minimum tillage approach to rape establishment using a subsoiler and followed by two passes with a cultivator to prepare the soil before drilling. Slug pellets were applied separately, so was rolling.

“Together with occasional poor weather post-harvest, this often delayed our rape establishment, pushing the rape crop back several weeks and putting us under pressure during an already congested early autumn window.

“With a lengthier rape establishment process, we also needed extra labour to complete the task, so when we lost one of our seasonal staff in 2021 the idea of simplifying the whole process from six or seven passes to just two was a logical move.”

To get the rape away earlier and reduce some of upfront costs, Mr Roberts purchased two new applicators from Cambridgeshire based manufacturer Techneat Engineering, mounting a Multicast Duo on the front linkage of a John Deere 8370R tractor.

Formerly known as the Terracast Duo, the Multicast Duo uses two separate tanks, metering units and control systems.

Cover crop

This enables Mr Roberts to apply rapeseed and a cover crop mix of buck wheat, Berseem clover and fenugreek that is direct drilled into stubble using a rear-mounted Cousins low-disturbance drill.

The Multicast 200 – originally marketed by Techneat as the Terracast V2 – is mounted on top of the Cousins machine via a T-frame. It is used to apply slug pellets in the same pass.

Both applicators use powerful hydraulic fans and Garmin GPS speed controllers to ensure each product is accurately applied via a distribution header.

“From an operator perspective the applicators were quick to set up, easy to calibrate and with in-cab control systems it’s easy to monitor application rates and check when you’re going to need to refill the hoppers.

“As our first tractor lifts a band of soil to establish the rapeseed in, simultaneously applying slug pellets and the companion crop, our second tractor follows behind with a set of rolls to roll the new crop down tight – effectively sealing in any moisture.

Key pests          

The two-pass strategy has been used to establish more 130ha of oilseed rape in the past two seasons. “It has successfully enabled us to get the rape away earlier, helping it to grow away from key pests such as cabbage stem flea beetle and slugs.”

“The applicators have ensured that what was once three separate tasks is now a single pass. And with the ability to establish 140ha of rape in a single week, bad weather is less of a factor when it comes to getting the crop in the ground.

“Although time saving is the key driver for us, it’s hard to ignore the economic benefits of reduced fuel and less labour, as well as the environmental pluses of protecting our soil,” says Mr Roberts.

“In 2021, using the minimum tillage approach of several passes to establish our rape we achieved average rape yields of 3.7t/ha. But the new two-pass approach and direct drilling into stubble saw us achieved average yields of 4.1t/ha this year.”

Beyond lengthening some of the pipework when setting up the applicators, no special modifications were required, and Techneat was hands-on in helping us with advice and support on tray testing once we were ready to calibrate.

“Given our initial success we may extend the use of the applicators to apply starter fertiliser when establishing our winter wheat or possibly on winter beans, should we decide to widen our current rotation to include pulses.”