There have been two serious potato famines in the UK. The Irish Potato Famine of 1845 to 1849 and the Highland Potato Famine of 1846 to 1857. Both were caused by a disease known as potato blight, proper name Phytopthora infestans, which damaged potato crops right across Europe from the 1840s onwards. This disease is a type of water moult. Spores infect the tubers in warm wet conditionas and then spread to the leaves. The spores can be washed back inot the soil by rain or spread great distances by wind. This makes it very hard to contain or eradicate. The blight shows up as blackened or mouldy leaves, rotting or scabby tubers are also a sign. Potatoes in storage which appeared healthy may also rot asa result of being infected with blight. Of course the massive number of deaths resulting from these two famines was caused by politics as much as the failure of the crops. Poor people farmed poor quality land and had no affordable access to the seeds and tools required to grow more diverse crops. Landowners were unwilling to diversify if the potat normally brought profits and an overdependence on the potato crop in wet and windy Scotland and Ireland is what led to such devastating consequences. It is estimated that between 500,000 and 1 million people died as a result of the Irish Potato famine alone.
