Fire releases these nutrients for the plants to use again. The exception is nitrogen. The nitrogen stored in the plant material is lost in the fire. During the burning process the nitrogen is released as a gas into the atmosphere. The plants will absorb nitrogen through other means.
Some nitrogen returns in the rain.
A fire-blackened prairie stimulates new growth. The black, sooty soil absorbs the heat of the sun which quickly warms the soil. This gives prairie plants a good start for the growing season. In restorations, fire also helps to reduce the weedy, non-native invaders of the prairie. Most invaders, such as quack grass and lawn grass, green up early in the spring.