AFTER a shaky start cell grazing is well underway at Higher Trevellett Farm, near Launceston, Cornwall.
Andrew Jones turned out turned store cattle out in mid-February to create a grazing platform, but poor weather impacted on grass utilisation and recovery in the cell grazing area.
As a result, some store cattle were moved to a sacrifice area of older ryegrass due to be ploughed up ahead of fodder beet.
Mr Jones says: “We are now stocked at 3,000-3,250kg live weigh/ha (as a comparison that
is double set-stocked cattle elsewhere) with cattle going into covers or 3,000-3,500kg DM/ha and grazing down to 1500kg DM/ha over a two-day period before being moved on.”
Mr Jones’s son, Oscar, is helping while James Daniel of Precision Grazing monitors grass growth and stocking rates to maximise use of fresh grazing.
Having weighed the beef cattle utilising the cells at turn-out, the aim is to take out more mature stock (500kg live-weight) into finishing yards in August as grass growth slows. Mr Jones says: “Last year we achieved an average growth rate across the season of 0.83kg/head/day purely from grass alone.”
Elsewhere, 380 replacement heifers reared for a local dairy farm have been turned out and set-stocked on permanent pasture. This had 30 units/acre of urea applied earlier in the season to kick-start growth.
Plate-meter readings suggest grass growth in mid-April was around 70kg DM/ha on more intensively managed ryegrass leys and lower on older, more established areas. Good ground conditions have also impacted on arable operations for the farm’s other feed crops.
Earlier drilled spring barley, Propino, has already emerged with a further 40ha (100ac) set to follow. The farm has established some using min-till cultivations to reduce costs over conventional deep ploughing.
Mr Jones says: “We’ve also drilled 110ac of fodder beet – variety Robbos – as a follow-on from older grass leys. Conditions were near perfect.
“A contractor will be here at the end of April to drill 40ac of forage maize – Glory – which has performed well in the past.”
Conscious that a run of good weather could break at any time, plans for first cut silage may be moved forward from early May. Mr Jones says: “The silage area had 100 units/ac of urea applied earlier in the season and while covers are not as high as I would like, I would sooner go for quality than quantity than risk being put back with weeks of rain.”
A contractor will be used to pick up mown grass with an aim of having it clamped between 36-48 hours after mowing.
THERE is still a large variation in grass growth rates nationwide, with a 56.2 kg DM/ha difference being noted this week across a number of beef and sheep units in the south of the country. Some farms have now achieved ‘Magic Day’, whereby grass growth equals demand by the herd or flock on the grazing platform.
Bill Reilly, AHDB grass and forage scientific officer, says: “Growth is beginning to surpass requirements and needs careful management to make sure future performance is not limited. Making sure the sward is utilised to its full potential is fundamental to this.”
Utilisation is a measure of the proportion of grass consumed versus what is allocated, and grazers should be targeting 85 per cent utilisation of grazed grass. Given the current rate of grass growth, some producers may decide to increase the rate of movement in a rotation.
Mr Reilly says: “Leaving excessive residuals after early grazings will limit the future performance. For beef, the target entry should be 2,500-3,000 kg DM/ha (8-10cm) with a residual of 1,500 kg DM/ha (3-4cm). In simple terms, put them in when swards are at ankle height and take them out when they are at toe height. Of course, this will be subject to ground conditions, which should be continuously monitored.
“Cutting to control paddocks that have gone beyond the ideal height for grazing (>3,000 kg DM/ha), or ‘resetting the sward’, is common practice in other parts of the world. Paddocks should not be ignored and just left to grow. It is important that producers focus on the quality of the end product and not just on getting value for money from the contractor by producing a bulky, stemmy crop.”
Regular monitoring of silage swards is just as important. The digestibility or ‘D value’ of silage is largely influenced by the growth stage at which the grass is cut and ensiled. Like residual grazing heights, cutting height will also influence sward regrowth. By raising the cutting height, grass plants are not forced to utilise energy reserves in order to produce a new leaf. This also reduces the interval between silage cuts or subsequent grazings.
Mr Reilly says: “Unfortunately, some producers still see ‘topping’ as an effective way of controlling sward growth. Recent research suggests that a cow can achieve the ideal residual grazing height of 3cm, whereas a topper can only ever cut to a height of 3.7cm. Allocating grazing areas and allowing for optimal utilisation means the need for sward control by mechanical means is reduced.”