After a dry spring a flush of early summer grass brings its own challenges for the Stobart’s who farm near Armathwaite in Cumbria.
The decision to allow grazing by sheep and cattle to take priority over silage making means some paddocks at Croglin High Hall, need to be pulled back into shape after a sudden flush of grass in early summer.
Jimmy Stobart says: “Along with my brother Thomas we had decided not to worry about cropping grass (for silage) this year and instead let grazing take priority. We were pinched in May but a sudden rush in June meant we had more grass than needed. Extra cattle were brought in to help manage the situation. We will also stock weaned ewes tighter to get covers down and quality back into those affected paddocks.”
Management of grazing has been challenged with the farm’s mower being out of action (some areas would have been pre-mown to protect the quality). And, again this year, much of Mr Stobart’s time through early summer is spent away from the farm contract shearing up to 25,000 sheep providing valuable income for the business.
He says: “First cut silage was eventually taken in early July either for the pit or round baled for feeding to ewes in winter. These cropped fields, along with lambing paddocks which were then grazed by cattle, will be used for weaned lambs.
“Some of these will have opening covers of around 2000kg DM/ha. Importantly, having been clear of sheep, we hope to have disrupted the worm cycle. Egg counts will be taken to determine what happens next. So far lambs have only had a white drench for nematodirus.”
Prioritising grazing has allowed some lambs to be weaned earlier than usual. Any cull ewes were marketed immediately to capitalise on stronger prices at Penrith mart before the annual glut followed. Mr Stobart says: “It is the third year we’ve done this. If the culls make £5/head more that puts just over £3/head on the lowland lamb crop which adds to the bottom line.”
Selling culls earlier also reduces pressure on grazing as summer progresses. This has been eased further by moving some stock on to allotments further away from the main lowland grazing. An area of 10.5ha (26ac) has also been taken on from a neighbour; this has been drilled with stubble turnips as a winter feed for tupped ewes.
Mr Stobart says: “Once we get towards eating into the ewe wedge in late summer we will begin selling lambs as stores.
“Having looked at our costs it is quite apparent a lot of time and cost is tied to finishing lambs away from the farm. Instead these will be sold either through private sales or via the mart.”
With off-farm seasonal contractual work easing, a return to focusing on livestock tasks at Croglin High Hall will allow the brothers to get back on top of grass management. In late August the farm will host an event with research institute Mordun looking at changes in lamb growth rate achieved through better use of grass.
Mr Stobart says: “What impact the decision to prioritise grazing over cropping grass will have may not be known until next season. But we aim to be flexible and will learn from what has gone on this year.”
As the grazing season progresses, good grass management becomes increasingly important to sustain sward quality for the remainder of the season. Preventing plants from growing a fourth leaf and dying will reduce wastage and the build-up of unproductive dead leaves in the sward.
Siwan Howatson, AHDB Scientist, says: “The key to restoring quality is to try and limit the area that needs attention, perhaps by sacrificing a field to ensure the other areas are maintained. It is very important to give the best pasture to priority stock, normally growing lambs, calves or cattle, so they are not disadvantaged.”
If the grass has got away there are a variety of options to help restore quality. It is important to make the decision of which management practice to use by looking at the fields and assessing individually for residual, rejection and seed heads.
Ms Howatson says: “Closing fields to be cut for late silage or hay increases the stocking pressure and will help control grass elsewhere. Be mindful of dung contamination and the last application of nitrogen to ensure the crop has fully utilised it (rule of thumb – grass uses 2.5 kg N/day).”
Another option is to move the animals off fields to tighten grazing pressure elsewhere and leave the grass to become standing hay for strip grazing by dry ewes or cows later in the season. This reduces the cost of making silage or hay but does mean the field will be out of the rotation for a longer period. Fields can also be topped, however, unless plants are reset to around 5cm, there will be limited benefit in terms of immediate grass growth.
Ms Howatson says: “If the stem is taken off above this height (classical topping of seed heads) the plant does not recognise its stem has been lost and further growth will not be stimulated. Removing stems and seed heads is likely to improve quality later in the season, as long as the amount left on the surface does not affect future growth. At around £33 per hectare, to break even on the cost of topping, an extra 400 kg of dry matter needs to be grown.”
Pre-graze mowing is used by dairy farmers to improve quality, however, stocking rates need to be tight to ensure animals eat it. However, research by Dairy NZ report that pre-mowing has no beneficial effect on animal performance.
Ms Howatson says: “To ensure livestock eat the allocated pre-mowed grass it is important that they enter the field with an appetite. A maximum cover of 3,000-3,300 kg DM/ha should be pre-mowed to make sure the sward is not too stemy and unpalatable. Potentially, there are more benefits to post-graze topping to meet residuals, ensuring high-quality pasture components are eaten and not wasted.”