With Britain in the grip of a heatwave, Professor Rosemary Collier, expert in agriculture and horticulture, comments on the impact that this prolonged period of hot, dry weather will have upon agriculture.
“The recent spell of very hot weather in the UK is having an impact on all sectors of agriculture. This is related directly to the effects of the high temperatures on crops and animals and, in some instances to the lack of rainfall, which, for example, has led to a shortage of fresh grass for livestock to feed on.
“In terms of the fresh produce industry, which is a sector that the University of Warwick works with closely, the high temperatures are having an adverse effect on the growth of certain crops such as carrots and lettuce, which have optimum temperatures for growth somewhat lower than the temperatures we are experiencing. Since crops like these also need a good supply of water to grow well, the ability to draw on water supplies for irrigation is essential.
“The hot weather has also had an impact on the pest insects that infest crops and insects such as aphids, thrips and caterpillars develop rapidly when temperatures are high and when they are not ‘knocked- back’ by periods of rainfall. In particular, the southerly winds have brought migrant moths, some of which are pests of crops. The Silver Y moth is particularly abundant at the moment and can be seen in gardens feeding on plants such as Buddleia. Its caterpillars can damage several types of crop, but particularly lettuce.
“The impacts of the hot, dry weather will persist well beyond the summer, particularly in terms of the supply of vegetables such as carrots which grow during the summer but which we harvest fresh throughout much of the winter”.