Measuring and calculating grass availability is helping a Welsh sheep farm to prevent forage shortfalls by flagging up impending deficits 10 days earlier than through visual assessment alone.
At Hill Farm, near Hay-on-Wye, Sam and Will Sawday and their mother, Penny Chantler, run a flock of 1,500 pedigree New Zealand Romneys.
They have been measuring grass for five years and in 2023 shared their growth data through the Farming Connect Welsh Pasture Project.
“Measuring and uploading the data to Agrinet has helped us to understand what our farm is capable of,’’ says Sam.
“It has been particularly important during the summer dry periods – the figures graphically show when growth is dropping.
“If we were doing that on eye alone we would be 10 days slower to act but we can anticipate those feed shortages and make decisions based on the data.’’
At 1,200ft above sea level, grass growth doesn’t kick in until the end of April at Hill Farm but by building organic matter and soil biology through mob grazing and reducing herbicide, insecticide and wormer use, the business no longer relies on synthetic fertiliser to produce feed.
Regenerative farming was a natural progression from their low-cost forage-only system.
The family produces breeding stock, fat lambs and stores from a pedigree flock of 1,500 High Country Romneys - 650 recorded stud Romneys and RomTex ewes and 850 commercial Romneys.
They are very keen on monitoring but the benefits they see are less clear cut than simply producing more lamb from an acre of land or at a higher weight.
Having more wildlife on the farm is indicative of a healthy system and that means healthy plants and healthy livestock and fewer inputs and treatments to get the same level of performance.
Grass measuring is done weekly during the growing season on the 61-hectare (ha) home block.
“We take a couple of measurements before we lamb in April and don’t measure during lambing because most of the farm will be set stocked then,’’ Sam explains.
After lambing, the flock is run in three equal mobs with short bursts of high impact grazing to encourage regeneration.
Paddock size varies but, to prevent re-grazing, the aim is to not graze sheep in the same one for longer than four days.
Historically, there were short rest periods of around 25 days when the system mimicked the New Zealand model but in the last few years the family has been trialling the tall grass grazing model - grazing a third, trampling a third and leaving a third – and are now at a point where they have a hybrid of the two.
Lactating ewes and lambs aged up to a year old will graze shorter covers, grazing 10cm down to 4cm, to ensure best quality.
Weaned ewes graze tall covers where applicable; this method increases rooting depth thus increasing environmental resilience and also allows plants to access more nutrients from deeper in the soil.
The longer rest periods also help to break the worm cycle, reducing the amount of drenching needed.
When the grass is measured it is done in a very uniform way.
“We follow the same route each time, the same pattern, measuring pretty much the same spots, it removes all the variables,’’ says Sam.
What it has shown is how variable performance can be from field to field.
“The most useful aspect is understanding what is there, what’s the potential and what are the ups and downs going forward,’’ says Sam.
“The more you measure the more you understand your farm and which fields to sub divide.’’
It also helps avoid situations when paddocks are over-grazed.
“Grass needs long rest periods but unless you measure you don’t truly know when stock was last in that paddock. It can be quite surprising how short a time it was since the last grazing,’’ says Sam.
Pregnant ewes graze 20ha of direct drilled brassica mixes of swedes, turnips and kale from
mid December to the end of February.
Once they have finished that crop there is a pre-lambing graze of the tupping fields before set stocking for outdoor lambing in April.
Fields are resown post-cropping with herbal leys, which are also measured.
“The herbals always outperform everything but they are often outlying measurements - they grow fast but dry matter is lower - so have to make some judgments. The same applies if you have more clover in the pasture too,’’ says Sam.
Measuring gave the business the confidence to graze some of the land with 90 dairy-cross steers this summer for the first time, in a grazing agreement with another farm, to build soil fertility and break the worm cycle.
It was the Farming Connect Master Grass course facilitated by Precision Grazing that first got Sam interested in measuring and he has since been a member of a Farming Connect regional discussion group.
Before he got involved in the Welsh Pasture Project he used the data shared by other farmers on the site to inform his own decision making.
“I would get an update every two weeks and I could see what was happening from region to region and how we compared.’’
Hill Farm is a business that doesn’t stand still and plans for 2024 are already evolving. “We are trying to improve our rotation and improve the balance between quality and rest periods and see what we can achieve,’’ says Sam.