By David Waite, BSc (Agric) Hons  FCII  FCILA  CFIRM  FUEDI-ELEA  PMIAgrM
Technical Lead – Agriculture - Charles Taylor Adjusting

The UK Met Office has issued its first ever Red Alert high temperature warning but some of the potential consequences to farmers may already have been laid by the recent dry conditions, which arise not only through drought but also from heat stress.

The current situation is unprecedented, so it is not possible to quantify the increased risks imposed by these high temperatures. The most obvious insured perils to be implicated are fire in cereal crops and heat stress in poultry, especially broilers, but the effects of uninsured losses on quantum can be easily overlooked, with claims being overpaid.

Cereals
The risk of fire is obvious in tinder dry crops, where fires can spread rapidly. In normal years good weather at harvest provides uninterrupted working and minimal drying costs but cereal yields are dependent on adequate soil moisture during grain fill so drought conditions can seriously impact both yield and quality, in the absence of fire. The extent thereof depends on many factors, including soil type, with heavy clay soils less at risk than lighter sandy and silty soils. In severe cases crops suffer early senescence, with significant yield losses. These possibilities are a real threat to cereal farmers who are depending more than ever on yield and quality to benefit from the current high prices to offset their record input costs but these specific losses – in the absence of fire – are uninsured.

Prolonged dry weather can make cultivations for the following crops difficult, with adverse effects on yield and quality in 2023. Irrigation can help but few cereal farmers have this facility. So, assessing quantum from previous years’ records, without attempting to allow for the uninsured effects of drought and heat stress, can easily overestimate the insured loss. Some modern plant breeding programmes include drought tolerance but meaningful results will take several years to become apparent.

Glasshouses
Modern glasshouses have computerised environmental controls programmed to increase sub-optimal temperatures to target levels. With high temperatures, cooling is limited to increasing ventilation by opening doors and roof vents, often with only marginal effect. In extreme cases internal temperatures can be so high that crop damage occurs and workers cannot operate, but these conditions do not represent insured losses.

Livestock
Grazing livestock should not be at drought risk if water supplies are maintained. The most immediate problem is the lack of grass for grazing, which also reduces the amounts available for hay and silage to form the basis of next winter’s feed programmes. Stockmen should be on the lookout for clinical signs of heat stress in all livestock, providing shelter where possible and adequate supplies of fresh water, especially where livestock are dependent on natural water courses. High temperatures in all livestock can reduce feed intake, causing depressed physical and reproductive performance, but none of these losses are insured. Pigs are more susceptible than cattle because of their inability to sweat.

Housed livestock should have adequate drinking water but, as in glasshouses, the potential to reduce high temperatures depends on maximising ventilation, often with limited effect. This can result in (insurable) heat stress, especially in intensively housed broilers where the heaviest birds are most susceptible. Temperature alarms are typically set at 30° C above ambient but, in extreme conditions, even maximum ventilation settings cannot cope and the birds succumb to heat stress with high levels of mortality, usually by mid/late afternoon. In our experience, and surprisingly,  the majority of the survivors continue to perform well.  High relative humidity exacerbates the problem. There is no strict trigger point for heat stress to occur, in our experience ambient temperatures of 30° C and above can be expected to cause problems.

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> Heat Stress in Poultry: Recognising it, tackling it and the Insurance considerations