Pasture Maintenance

Our pastures are grazed by sheep, horses and chickens, and some are cut for hay. The pastures don't look after themselves though, and require human intervention to maintain them.
 
Why? There are three main reasons for pasture maintenance on our farm:
 
1)  to provide our animals with food;
2)  to conserve natural biodiversity;
3)  to control vegetation in the orchards.
 
How? Each of these three reasons has a different maintenance approach, and combinations are also possible. The farm is divided into different plots, by fences, walls, and hedges. We have decided on an objective for each plot, and this has led to specific maintenance regimes, forming part of what is known as a "compartmental management plan". Objectives and maintenance regimes can change over time, according to need, but we try to change them as little as possible, as this can damage years of good work. It was important to settle on objectives that are achievable, and regimes that are maintainable. To indicate what these are, we observed the local pastures, saw how they are used and maintained, spoke to local farmers and other pasture-users, and studied the historical uses of the land. Stocking density is an important factor. We keep sheep numbers at around 30 to 35, which we believe is the correct amount for our 8-hectare farm, to keep vegetation down during the summer whilst still leaving enough to be cut for hay for the winter. We also need to be able to graze our two Asturcon ponies. Overstocking can lead to trampling, and the need to import winter feed; understocking can lead to the pastures getting out of hand, with livestock lost in a jungle; optimum stocking density varies from season to season, and we need to take this into account. 1) Animal food.
 
If we didn't maintain our pasture it would start to revert to forest, which for us would initially mean brambles, accompanied by other species which our livestock find unpalatable. When a pasture has been grazed, the plants that are left untouched are the ones that the livestock won't eat, such as brambles, nettles, bracken, thistles, and gorse. If these are left unchecked they can take over, gradually eroding the edibility and therefore usefulness of the pasture, which can result in the pasture being lost. It's a vicious circle. This is where the maintenance comes in, removing the unpalatable (undesirable) species so that the palatable (desirable) species can grow. Removal of undesirable species can be done by hand or machine, depending on the species and the extent of the problem. To prevent the problem returning, removing the roots is a good idea, and tackling the plants before they set seed is essential. "One year of weeds equals seven years of seeds". We remove the unwanted plant material from the pasture, and either compost it or brash-pile it, depending on the species, its woodiness, and whether composting will destroy the seeds or not. Because we are an organic farm, we rely on a rotation of animals around the pastures to keep our livestock healthy. The majority of our pasture is grazed by our two horses, and our flock of sheep, in rotation, so that neither horse parasites nor sheep parasites can increase to problematic levels. The pasture takes time to recover after one grazing ready for the next. Horses can eat the sward lower than the sheep do, and they will also eat taller grass then the sheep will, but they don't like going into a plot of land soon after the sheep. Farmers in our area tend to graze their horses first, to eat the grass down to a length that the sheep can get at, then they remove the horses, wait a little while, then put the sheep in to finish the job. The passing of a flock of sheep-hooves helps spread the horse dung, and therefore the nutrients, across the pasture. Our chickens have a free run of the farm, doing their bit by eating parasites all day every day. Parasites include things like ticks, flukes, and parasitic worms. Our pasture is either grazed, or cut for hay to provide winter food. Grazing takes place year round, though we must remember when deciding on the regime that it's impossible to have the same set of animals in two different places at the same time! We make hay while the sun shines, in late June or early July. Cutting hay removes all growth to just above ground-level, whether palatable or not, thus helping to keep undesirable species under control - this is the main advantage cutting has over grazing. 2) Biodiversity.
 
 
Three areas of our farm are managed particularly to maintain natural biodiversity, in particular of wildflowers, with the secondary objective of providing food for the sheep. The "Wildflower Meadow" is grazed once by sheep in the winter, and cut for hay in early summer. "Castañarina Meadow" is grazed once by sheep in winter, cut for hay in early summer, and grazed by the horses once in late summer except for the areas which were cut for hay. "Cuevona Meadow" is grazed by sheep three times a year. Each of these three regimes varies the habitat slightly so that the species found there also vary (this also depends on other characteristics of the plot of land). Traditional hay-meadows such as ours are renowned for their wildflowers, due to not using heavy machinery or fertilisers on the land. Each pasture has two eruptions of wildflowers, one in spring and one in autumn, and it is important not to graze or cut the pasture until those wildflowers have set seed for next year. Equally importantly, we don't keep the livestock too long in any one pasture, as overgrazing and overtrampling can devastate some wildflower populations, especially orchids. 3) Orchards.
 
 
The chief objective for the three orchards is to produce a commercial apple crop, and the secondary objective is to provide grazing for our sheep. Luckily these go hand in hand, with the sheep eating the vegetation beneath the trees, thus making our task of collecting the apples a lot easier. Each tree has a sturdy guard around it to prevent damage (livestock will eat the bark). The orchards are probably subjected to the heaviest grazing pressure of all areas of the farm, as evident in their lower levels of biodiversity (though still good, and still important). They are grazed in strips by the horses in winter and spring, using temporary electric fences to enclose the strip and to prevent the horses damaging the apple trees. Horses tend to rub themselves on the trees, especially during their spring-moult, which can snap the trees or push them over. Once apples have started to appear on the trees there is a danger of the horses choking on them, so the horses need to go elsewhere. The orchards are then grazed by the sheep several times throughout the year. By October, when the apples are ready for picking, the grass beneath the trees must be short enough so that we can find all the apples, yet the sheep must not have been there recently enough to have polished off all the windfalls, or the apples on heavily laden branches that have bent to within their reach. A good side-effect of having livestock in the orchards is that the constant sound of their hooves helps deter mole-rats - these rodents can feed on the roots of the apple trees, killing them. Keeping vegetation down in the orchards also helps birds of prey see the mole-rats, as a natural control measure.
 
Information sheet created by Hotel Posada del Valle. (www.posadadelvalle.com)
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