Flexibility essential for establishment policy

OVERBURY FARMS, OVERBURY, GLOUCESTERSHIRE

Many farmers will feel the 2012 harvest is proving scarily like 2008 when combines were rolling well into September before a rush to get following crops established.

With harvest running around 10 days later than normal and catchy weather for much of August, Jake Freestone is no exception. The desire to get on with fieldwork may be overwhelming, but he believes patience and flexibility is vital.

The farm has spent several years improving soil structure through minimal tillage, organic manures and a variety of cropping measures, so he is keen not to undo the good work by working land when it’s too wet or by excessive travelling on fields.

He knows this patience further reduces the cultivation window and says normal routines often need to be changed to get crops in on time.

“For example, we often bale wheat land going into rape and apply poultry litter for autumn nitrogen and a fair chunk of P and K. But this year it’s been too wet for that extra travelling on fields, so we’ve been chopping straw and not using the poultry litter. We may go on with some in March for spring nitrogen.”

Trying new things

One of the main changes for this season was on the heavier land where 50ha of Camelot oilseed rape after wheat was established by spinning it on through a slug pelleter on the back of the Bateman sprayer before the wheat was cut. “It can be a very hit-and-miss process, but if we’d tried conventional establishment, I think we’d have struggled to get any crop in at all this year and who knows what it’d have done to the soil structure in the process,” says Jake.

Cleaned, untreated home-saved seed has been used at a rate of 5kg/ha or 100 seeds/sq m, well above the 2kg/ha normally used with conventional drilling. “There is an increased seed cost, but it’s not dressed because it’s gone on to a standing crop and is home-saved, so there’s just the cleaning cost.”

Total establishment cost (excluding seed) is around £5/ha, versus the £75/ha it would have cost using the normal approach of a pass with the Vaderstad Topdown cultivator, leaving for 10 days before spraying off, then going in with the Vaderstad Carrier + BioDrill and rolls.

“I’m hoping we’ll get 50% establishment, or 50 plants per square metre. If it works well, we could end up with more and quite a thick crop, but I’d rather be trying to manage that than one that’s too thin. If it goes well it may be something we’ll consider again and if it fails, hopefully it won’t have cost us too much and we’ll still have time to get another crop in.”

Not disturbing the soil could also lead to some saving from using less residual herbicide, although with products going on to straw and longer stubble he is yet to see how efficacy is affected. He also worries that slugs could be a major issue due to more surface trash and the wet conditions during August.

Simplifying tillage

Cultivations have also been simplified on another 20-30ha block of heavier rape ground which was raked and rolled straight after combining to encourage volunteers and blackgrass to chit. These have been sprayed off at an early (cotyledon/one-leaf) stage with 0.75 litre/ha glyphosate and repeat applications may be used if needed, before drilling directly into the stubble.

“With a 6m rake doing 8ha an hour and rolls doing the same, it’s a very quick, cheap and effective way of controlling blackgrass and volunteers, especially compared with the Topdown at 3ha an hour,” says Jake (see table 1). “It is important to spray the plants at an early stage, though – leaving them longer doesn’t necessarily mean more will germinate and means those that are there will get bigger and require higher doses of active ingredient.”

Strict harvest management was employed on these heavier fields, with trailers restricted to headlands and field travel kept to a minimum, he adds.

Cover crops

Another change for 2012-13 is the use of cover crops, which will be sown into wheat stubble to increase soil organic matter and structure ahead of spring-sown barley.

Mustard has been used before, although winter beans will also be tried for the first time this autumn, to provide some residual nitrogen. Home-saved seed will be used to keep costs down, and will be established using the BioDrill on the back of the Carrier.

A small 4ha trial area of Compass oilseed rape is also being sown with a companion crop of legumes (clovers and vetch). All seed is sown together and Jake hopes there will be a smothering effect on other weeds, while the legumes should die out over winter and leave behind around 40kg/ha of residual nitrogen.

“When you get a harvest like this, it really brings home the value of having a mix of cropping and good rotation,” says Jake. “We’re fortunate to have a real variety of soil types from the Cotswold brash at altitude to heavier clay in the river valleys, which also gives a natural staggering to harvest.”

However, it creates challenges too, especially as he likes to get barley on the higher ground drilled before the end of September in order to get crops established well before winter. “With wheat coming off late, there will be a battle to get volunteers cleared up before planting barley. I don’t like to delay barley drilling at altitude, but if the weather’s right we should be OK,” he says. “We’d normally sow 350 seeds/sq m, but could increase this to 425 seeds/sq m if drilling is delayed until the first week of October.”

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