Causes of the Irish Potato Famine
There were many factors that caused the potato famine, the main factor being an air born fungus, Phytophthora Infestans, that spread quickly in the Irish climate and destroyed the potato crop. The potato blight, or Phytophthora Infestans, was first found in the America's in the early 1840's and was transported to England on the holds of ships. The summer's climate during the year of 1845 was mild and wet, which was perfect for transporting the blight.
How the Potato Blight works
The blight thrives in a warm and moist climate, the fungus grows and spreads quickly and can release up to one million spores per day. in the beginning it attaches itself to a plant and is very small and whitish, so small that it is barely noticeable to the human eye. The fungus then produces spores and ravages the plants juices and tissue. The remainder of the plant then nourishes the spores and helps them to reproduce and spread. The spore travels best in the wind, by being blown around, and rain, by being pushed around in the soil by the water. The fungus is killed by cold weather, however if diseased seeds are planted the blight will come back and continue to spread