One of the biggest benefits of lightning, believe it or not, is that it causes fires. We usually see fires as a bad thing that destroy plants and property. Lightning starts about 12 percent of all forest fires in the United States, with over 60 percent of these in the Rocky Mountains area and fewer than two percent in the East; most lightning-started fires burn fewer than 10 acres of growth. But botanists and other scientists have long known that fires are beneficial to keeping forests and grasslands healthy. Many plants, indeed, drop seeds that can only germinate after they have been burned, and fires clear away old growth and allow new plants to thrive.

Another benefit to both plants and animals is that lightning strokes convert gaseous nitrogen (N2) into nitrates (NO3) by adding energy to the air, which causes nitrogen atoms to bond with oxygen. Nitrates are a vital part of the food chain; plants need them to survive, and animals get them by eating plants or other animals that eat plants. About half the world’s naturally occurring nitrates are created by lightning (the other half is generated by bacteria living inside plants such as legumes). Scientists estimate that 200 billion pounds (91 billion kilograms) of nitrates are created every year through the action of lightning. In other words, without lightning, plant and animal life on Earth would be severely depleted.