Double OSR Benefits for Borders Dairy Business

Unusual both for the area and enterprise, oilseed rape is proving valuable in more ways than one in the Laird family’s Peeblesshire dairy business.

Following success with the crop in their arable rotation further north at Kinross where they rear their dairy youngstock, the DK Exsteel grown at Blyth Bridge last season produced a very encouraging 5.5t/ha. At the same time, it yielded a handsome crop of straw as quality bedding for the award-winning 550-cow pedigree Holstein herd, currently averaging 12,200 litres/cow/year.

“Cow comfort is a big thing for us,” explains Colin Laird. “OSR straw is more fibrous than cereal straw, so it breaks-up easily and separates out well. Most importantly the cows really like it in their deep bed cubicles, and you’ll struggle to find cleaner cows than ours.

“As well as rewarding us well through the combine, our DK Exsteel grows good and tall. It’s difficult to estimate the actual straw yield, but it is definitely also a bumper crop in this department. And it is proving a good cleaning crop too, providing a much better entry for our seed wheat-growing than grass.

“OSR helps to make our high-production dairy system as sustainable and self-sufficient as it can be,” he points out. “We mainly feed our own home-grown cereals from Kinross in a total mixed ration with grass silage and don’t have the option of maize. So, it fits really well in our rotation here.”

Once again, this year’s 17ha of DK Exsteel has established well after grass at Blyth Bridge.Despite some problems with cabbage stem flea beetle, its early vigour enabled it to pull away strongly.

When it comes to growing the crop – both at Kinross and Blyth Bridge – Colin Laird relies heavily on the experience of his Agrii agronomist, Iain Anderson who explains that the local soils and climate are very well suited to the crop.

“Scotland is prone to soils with low pH, and OSR is fairly tolerant,” he notes. “Club root can be a problem where large amounts of swedes, turnips or other brassica fodders are grown, but that’s not an issue here.

“OSR fits-in well after grass leys which tend to sop-up the nitrogen and hold back a following cereal. The OSR blasts on through, though.

“We have always found hybrids far more reliable. We were growing DK Exalte at Kinross but are now moving entirely to DK Exsteel. We really like Dekalb hybrids for their excellent vigour and speed of development. What’s more, their pod-shatter resistance brings us valuable peace of mind at harvest time.

“DK Exsteel is suiting us very well,” reports Mr Anderson. “Along with autumn vigour, it also gives us just the sort of spring growth we need. It isn’t desperately quick out of the blocks, but keeps going, putting on good growth. It grows tall with a thick stem and puts out plenty of branches, which is what we like to see.”

At Blyth Bridge, land coming out of grass is ploughed before OSR, but the barley stubble at Kinross gets a pass with a 3m Sumo Trio before the crop is drilled into the medium loam soil with the farm’s 4m Horsch Pronto.

“We aim to get our OSR established in mid-August,” says Mr Laird. “That can mean a clash with spring barley, which we usually haven’t harvested by then, so our OSR at Kinross mostly follows winter barley.”

At 50 seeds/m², the team consider their seed rate a little on the high side for a hybrid, but insist they’d rather be looking at a crop in the autumn than for it; especially so, as it isn’t unusual for young crops to suffer in a harsh autumn at their 200-300m elevation. They generally expect only around 50% establishment, even with a hybrid.

Agrii-Start Release applied at drilling gives the crop 30kg N/ha with 40kg/ha of protected phosphate to help it get underway. Boron is also applied as tissue testing at Kinross has revealed a general lack of both boron and molybdenum.

Metazachlor goes on at early post emergence to keep broadleaved weeds at bay, with a follow-up graminicide applied in early October. A strobilurin fungicide with a growth regulator at this stage helps to keep the crop canopy in check.

“Light leaf spot is a particular problem up here,” reports Mr Anderson. “So, our focus is on preventing it from taking hold. DK Exsteel’s resistance rating of 7 is really useful, allowing us to keep the crop well-protected with our fungicide programme.

“The crops don’t really get going until early March and we often get late frosts. So, we prefer varieties that don’t flower too early, as well as those that are especially good at compensating for any early pod loss.”

The Blyth Farms’ OSR gets its first dose of N fertiliser once soil temperatures climb above 5°C. This is accompanied by 50-60kg/ha SO₃ and followed by two splits of nitrogen. As the land isn’t hungry, it generally only receives 160-180kgN/ha in total.

Molydenum and boron are applied at stem extension, with magnesium added at flowering. Kestrel (prothioconazole+ tebuconazole) keeps LLS at bay while just one ‘well-timed’ strobilurin is applied at flowering to check sclerotinia. This is also designed to keep the green leaf area going for as long as possible to take advantage of the long, mid-summer days.

“It's care and attention throughout the season that results in OSR that performs,” stresses Mr Anderson, digging-up a plant to illustrate his point. Along with a strong tap root, there’s a thick ball of roots with a strong, stout stem, branching well.

“DK Exsteel’s big, thick stems are great for growth and for keeping the crop standing, although they do take some desiccating with Roundup (glyphosate) at harvest!”

Mr Laird recognises this care and attention means a considerable investment in the crop, especially at a time when input prices are rising fast.

“We used to consider OSR as just a break crop but now it has to be more than that,” he concludes. “After all, we want to make at least an extra pound for every one we spend on it. With our cows we’ve always found performance is so much better if you look after them well, and it’s much the same with our OSR.”