They are called bush in Australia. In North America grasslands are called, you guessed it, prairies. All prairies are different in the amount of rainfall and the seasonal temperature. Prairies are usually found in places that don't get a lot of precipitation. There's not enough rain to support a forest, and more than enough to support a desert.
Some prairies have short grass, some have tall, and some have mixed grass.
Most tall grass prairies are to the east, the short grass to th west, and the mixed grass in the middle. The mixed grass prairie connects the tall and the short grass together. All of these prairies are in North America. This is a picture of a tall grass prairie.