Fodder beet is potentially the UK’s highest yielding forage crop, but there’s a lot to get right to achieve optimum performance, and a new threat to manage.
Given its potential for very high output, fodder beet is an attractive forage option for dairy, beet and sheep producers.
A typical breakeven yield is 50t/ha, but yields approaching 100t/ha or more are possible if the crop is managed well, says Pembrokeshire-based Agrovista agronomist Lyndon Harris.
Variety choice is key, but not always straightforward, as much data comes from breeders’ trials carried out in arable areas of the UK or Europe.
“That was a bit of a concern, so I set up my own variety trial to produce more meaningful information,” says Mr Harris. He now has three years’ data covering a range of material from different breeders grown at Berwyn and Hedydd Lloyd’s Pencwm Farm, near Moylgrove in north Pembrokeshire.
Over that time, average fresh weights range from 58t/ha to 99t/ha, dry matter % from 15% to 26% and dry matter yield from 12-19t/ha (see graph). Other important factors when choosing varieties include dirt tare, which usually correlates to skin smoothness, as well as rooting depth and frost hardiness.
Taking all these factor into account, Mr Harris has come up with a list of preferences for various categories:
All-rounder: Cagnotte gives high fresh weight yields, reasonable DM yield, smooth yellowy skin. It is similar to Robbos but ahead on yield. Merveille, a red beet, has a fractionally higher yield but is less smooth. Blaze hits top yields in high-fertility soils.
Grazing: A soft flesh (lower DM) root is required with more than 50% above ground and lots of leaf. The obvious choice is Jamon, a smooth-skinned yellow beet, but Brunium is also interesting. It is higher yielding, has sufficiently soft flesh at 15.7% DM but less root is exposed.
High DM beet: These varieties are suited to harvesting, producing maximum energy levels/ha without the need for grazing succulence. They are generally white, deeper-rooted varieties harvested with a bottom lifter. Eloquenta has the highest dry matter yield; Magnum still performs well and is the only higher DM variety that can be harvested with a top lifter.
Good agronomy is important to maximise output. “Phosphate can be limiting in the first 30 days and applying Phosphorus Liberator, which is based on carboxylic acid technology, to the seed-bed frees locked-up phosphate and keeps it available,” says Mr Harris.
Maximising root development and leaf cover in the first two months will help build yields. “Two applications of plant-derived foliar amino acids such as Terra-Sorb Foliar Extra will help fine-tune performance,” says Mr Harris.
Retaining green leaf is crucial to raise yield in later harvested or grazed crops. “Two fungicides and a late application of nitrogen are worth considering,” he adds.
A new challenge in some areas is beet yellows virus. Unprecedented levels, combined with drought, decimated yields in some crops in Mr Harris’ area last year.
Rothamsted insect survey figures show populations of the vector Myzus persicae (peach potato aphid) peaked six weeks earlier than the 10-year average in 2020 and numbers were roughly nine times higher.
“Treatment had not been needed in some parts of the west – this has now changed,” says Mr Harris. “I will be trialling Maruscha, a tolerant variety, this year, but it’s a high-DM, sugar beet-type variety that will have limited appeal in this area.”
Yellows virus had a big effect on last year’s beet at Pencwm Farm, where Berwyn and Hedydd, with help from the next generation Griff, Meryl and Emily, farm 120ha of grass, supporting 150 pedigree Limousin beef cattle and calves, as well as 80ha of arable. The disease is a concern given the crop’s importance.
Beet is a key ingredient in the diet. The daily growing ration consists of 5kg beet, 2kg alkali-rolled barley and ad-lib grass silage, while finishers receive 9kg of beet, 5kg of alkali-rolled barley and ad lib grass silage. Excess crop is also sold to neighbouring farms.
Beet is typically sown after direct-drilled kale. While this fits well, kale can act as a reservoir for aphids. The Lloyds will now ensure all kale is consumed or desiccated in good time before ploughing ahead of the beet crop to minimise aphid transfer.
“This should provide enough of a break,” says Mr Harris. “In an ideal world, growers should start by selecting a field that hasn’t grown beet for two years, and avoid planting near Myzus persicae host plants, including brassicas, potatoes and legumes.
“And be sure to monitor aphid numbers – thresholds are one green wingless aphid/four plants up to 12-leaf stage, and one per plant at or after the 12-leaf stage. If threshold is reached, apply flonicamid (Teppeki) at 0.14kg/ha.”
Agrovista fodder beet trials – Pencwm Farm
