The muir-burning season ended yesterday after a spring that saw some spectacular, out-of-control hill fires as a result of the unusually dry conditions in March.

Muir-burning is practised by hill farmers and land managers to burn off rough, hill grasses and long, mature heather to improve grazing for sheep and grouse.

Coarse hill grasses like Mollinia and Nardus can become rank and tussocky if not grazed down or burnt, and will smother out heather. Apart from the fact that those rough grasses are unpalatable to cattle and sheep, they also create a snug environment for ticks to over-winter.

Like mosquitoes, ticks transmit deadly diseases to cattle, sheep and grouse, as well as Lyme disease to hill walkers when they bite to gorge on blood – but the main reason for muir-burning is to create patches of short, sweet heather for sheep and grouse to graze.

Next time you are driving through heather-clad hills where muir-burn is practised you should observe the patchwork of different stages of heather and understand why the hills look like that.

The idea is to have patches of mature heather where grouse can safely nest without being spied by raptors like hen harriers, as well as adjacent patches of young, short heather, suitable for grazing. Ideally, those patches should be long, narrow strips, so that grouse are never far from cover when they venture out to nibble the young heather shoots.

By now, the reader will have gathered that rotational muir-burn isn't simply a matter of dropping a match and letting the hillside burn out of control. It takes a lot of planning and staff, but, as with all fires, there's always the risk of changes in wind strength and direction that can lead to a major conflagration. When that happens, it often takes many extra helpers, sometimes assisted by the fire brigade, to get it back under control.

Failure to do so could destroy habitats over hundreds of acres and threaten adjacent forestry.

I had about 300 acres of moor when I was farming that I would have loved to set a match to it every spring, but two adjacent Sitka Spruce plantations made that far too risky a venture. Instead, I grazed it hard with beef cows during the early summer. That certainly kept the moor from becoming too rank, but the cows never milked as well as when they were on better pasture. As a result their calves weighed less in the autumn.

It was a matter of balance. While the cattle did not perform as well, the sheep did better because they prefer the shorter, sweeter grasses created as a result of the cows' non-selective style of grazing.

Those on the high hills do not have enough cattle to graze them down, and, anyway, it's nigh on impossible to control where they graze in the absence of fences – hence the need for muir-burn.

The recent proposal by the European Agriculture Commission, as part of its current review of the Common Agricultural Policy, to deny hill farmers their Single Farm Payment (SFP) if their pasture contains more than 50% heather, flies in the face of all reason.

Heather has traditionally been regarded as an important food source for sheep. Lambs fattened on heather have a distinctive flavour and are highly regarded by many gourmets – indeed my local butcher reckons it's one of his best sellers.

More important is the fact there are hundreds of thousands of breeding ewes on our heather-clad hills. Surplus females from those hills, like older, or draft ewes, and ewe lambs are an important source of breeding sheep for upland and low-ground farmers.

Scotland has a stratified sheep industry where breeding sheep from hills are crossed with prolific sires like the Bluefaced Leicester to produce females that are then subsequently crossed with meaty sires like the Texel or Suffolk. That way the industry exploits the benefits of hybrid vigour.

Considering the amount of effort that goes into managing heather for grazing, and the fact it is a nutritious source of feed for sheep, the European Commission's proposal not to pay SFP on predominantly heather grazing is considered unreasonable in the eyes of hill farmers.

Fortunately, there is still plenty of time to lobby for the status quo. Failure to do so successfully will lead to the loss of vital support for hill farmers who cannot survive without the SFP. As a result, even more sheep will be removed from our hills leading to a further deterioration of habitats on Scottish hillsides.