🇬🇧 Maintaining Soil and Stock During Wet Weather

What Continuous Wet Weather Can Do to Soil Structure

Soil is at its most vulnerable when wet, so prolonged wet weather can be damaging. Typically, healthy soils contain air pockets. This allows oxygen to circulate, promoting microorganisms as well as creating good soil structure. If soil becomes waterlogged, then these pockets of air are pushed out, thus reducing biological activity. Waterlogged soils are more prone to compaction, so cultivation should be kept to a minimum or paused until conditions improve.

A loss of soil structure can cause it to slump. When this soil eventually dries it can form a hard-set layer which is difficult to cultivate or benefit from livestock trampling faecal matter into it.

How Wet Weather Affects Sheep

Lambs with wet wool use a lot more energy trying to keep warm, which can affect how quickly they finish. They spend more time sheltering from the adverse weather rather than grazing. Poor weather conditions also make sheep more susceptible to some conditions. Dermatophilosis and flystrike can spread more easily, and foot rot is more prevalent and contagious during wetter weather. You. might also want to do worm counts more frequently during prolonged wet weather. Leptospirosis may also be problematic and can be passed onto dogs, pigs, humans and horses.

If wet weather is followed by a period of warm sunny weather, then grass can grow rapidly. This often means minerals in the grass are diluted such as cobalt and magnesium and that affects lamb growth rates and increases their risk of getting staggers.

How Wet Weather Affects Cattle

Mineral levels in pasture affected by wet weather also have consequences for cattle. Grasses reduce their uptake of minerals in waterlogged soils. Heavy metals are sometimes absorbed more easily by the plant subsequently affecting the availability of magnesium, calcium and phosphorus.

Some parasites thrive in wet weather. Lung worm matures in cow pats lying dormant until the rain washes the faecal matter away. Infected pasture is then ingested by the cattle. In warm, wet conditions, this lifecycle (releasing hundreds of larvae), can take as little as five days.

If you have the ability to move troughs, this is another way that can prevent further soil damage as stock congregate in the area.

Other Implications of Wet Weather and how to Prepare

Excessive rainfall effects the amount of slurry produced by dairy farms. Contaminated standing water is detrimental to the environment and unlidded slurry tanks fill up more quickly. Spreading slurry on waterlogged soils is also problematic; it runs off the land and can contaminate waterways.

Furthermore, waterlogged soil means drilling isn’t possible as machinery can get stuck as well as it damaging seeds. Of course, this will affect harvests and result in losses for arable farming and livestock feed. Limited straw production affects livestock farmers who must look elsewhere for bedding. With more livestock housed indoors due to the poor conditions even more straw is in demand and shortages can occur quickly. Of course, straw costs are likely to rise when there is a shortage.

Indoor-housed animals have to rely on conserved feed. Buying in silage and hay, and straw or sawdust for bedding, for prolonged periods, adds to farming costs.

Outwintering livestock could help to alleviate some of these problems. Not all soils will tolerate this but for those that can, animals can be regularly moved from field to field throughout the wetter winter months. If done effectively, this can reduce housing costs, rejuvenate the soil, and improve animal production. For more information about outwintering, see our blog post ‘Outwintering.’

Straw Pads

If this method isn’t appealing, then creating a ‘straw pad’ is another alternative to housing livestock during winter months. This is an outdoor paddock bedded with straw which is replenished regularly. It has all the benefits of outwintering cattle such as improved animal health and welfare, reduced pasture damage and land poaching, but it doesn’t require solid housing and the associated costs.

Wet weather can also mean poor straw. Storing large straw bales can be challenging but leaving them in the field can be costly. There are now hay bale stack covers on the market which can cover large stacks and keep them dry during periods of heavy rain, minimising losses.

Short Term Mitigation

Moving cattle around regularly during wet weather can reduce damage to both pasture and soils. Well-drained fields or sacrifice fields help to minimise the impact. Grazing management is important to ensure a resilient pasture. Overgrazed grasses recover slowly and sustain more grazing damage during wet conditions.

Calving and weaning can take place indoors to avoid damage to fields. There are advantages to this in that farmers can keep an eye on the animals and have more control over the weaning process. You can release calves onto pasture earlier with cows joining them later when conditions improve. Housing heavier cattle for longer whilst lighter animals are out to graze reduces ground damage. The concern with indoor rearing is the risk warm wet conditions pose to calves developing pneumonia.

Driving heavy machinery along farm edges can destroy field margins. Swapping a tractor for a small Kubota or similar to check livestock, for example, can reduce the impact heavy tyres have on the soil.

Longer Term Options

When establishing new pasture, often grass that has been sown using a no-till method withstands wetter weather better than grass established on tilled land. Maintaining a heavy sod can increase pasture resilience. You can achieve this by overseeding, avoiding over-grazing, and regularly testing soil health and making adjustments to maintain it. Withdrawing moisture from the soil by planting a cover crop can help to alleviate some pressure from excessive rain. However, crop residue such as stubble, can help maintain soil structure and drainage of soils.

What Can We Learn from Other Countries?

Farmers in Bangladesh, renowned for its heavy monsoons, have adapted their agriculture to a very wet climate. During the dry season, they pump vast volumes of groundwater onto their rice paddies. This has tripled their rice production and, whilst their groundwater almost runs dry each year, as soon as the monsoons arrive the aquifers are completely refilled. This method of farming significantly reduces the amount of flooding when the rains come.

Other Bangladeshis have turned to ‘floating farming’ whereby fruit and veg are grown on floating mats of vegetation. This means that they can farm year-round regardless of the weather.

In New Zealand and the US, methods to mitigate effects on livestock are similar to those employed in the UK.

Conclusion

Whilst we cannot control the amount of rain that falls, we can look to plan grazing to alleviate harm to both soil and stock.

What to know more about AgriWebb’s grazing records? Find out more here.