• A single acre of reasonably fertile cropland can yield an annual harvest of 6 tons of potatoes. Because they grew so well in Ireland, they became a staple crop. They were easy to grow even in difficult soils; were impervious to invading armies who tended to burn down wheat and oat fields; did not require a trip to a mill but could be taken directly from the ground to the cookpot; kept well all winter long; and were nutritious.
• By the late 1700s, a typical Irish family of six consumed about 250 lbs (113 kg) of potatoes every year. It was the mainstay of their diet.
• The Irish were so dependent upon the potato for sustenance that when the potato blight first hit in 1845, killing one-third of the crop, they were left vulnerable. When the blight spread over the course of the next two winters, leaving potatoes blackened and mushy, the populace began to starve, and became vulnerable to diseases.
• It’s estimated that half of Irish people born between 1830 and 1930 left Ireland, fleeing from the famine. It wasn’t until 1996 that Ireland reported a net gain in population instead of a loss.
• Although the potato blight also hit the U.S., there were so many other crops being grown in America that no one starved.
• It was years before researchers understood that a fungus was responsible for the potato blight. When potato farmers piled old potato vegetation at the edges of their fields, they were unknowingly stockpiling the source of the infection by providing an unending source of spores. When the weather warmed in the spring and fresh new potatoes were planted, the spores blew in the wind. If they landed on potato foliage while the leaves were wet, they infected the new sprouts.
• Once the fungus landed on a potato leaf, it bored into the plant, releasing enzymes that digested the plant to provide nourishment for the fungus, which also killed the potato plant.
• The potato tubers were safe as long as they remained underground, but would turn to mush as soon as they were dug up and exposed to the fungus spores floating in the air.
• Because the fungus needed to land on wet leaves to survive, the blight was particularly bad during the extra rainy season in 1846, tapering off somewhat during dryer years. Blights recurred in 1872 and 1879, but by then Irish farmers had grown less dependent on potatoes and had other crops growing.
• By 1890 it was discovered that the blight was killed if a field was dusted with copper sulfate, ending the blight for good.
• Today, about 20% of the U.S. population claims at least partial Irish history due to the blight.
• In 1914, German authorities ordered that all surplus foodstocks were to be stored in the cities. Thousands of pounds of potatoes were subsequently stored in damp, warm, humid basements. A few of the spuds carried spores of the blight with them, where they found conditions perfect for replicating. The entire supply turned into a back mushy mess. A year later, as Germans struggled to feed the country during World War I, copper was in such short supply that there was none available to create the copper sulfate needed to keep the blight at bay. The crop failed two years in a row and the populace began starving. Some historians feel that the population was so weakened by shortages caused by the blight that their downfall was already in the making by the time the U.S. joined the fray in 1917.
