English: This diagram illustrates trophic cascade in an environment. The cascade to the right shows a healthy ecosystem with a top predator, a primary consumer and a primary producer. The wolf at the top of the cascade is the top predator of the environment. The top predator makes sure that the deer and elk populations stay at healthy levels. This in turn relieves grazing pressures from the primary producers. This allows all the animal populations to stay in balance with each other. However in the cascade to the left the top predator is removed. The deer and elk population is then left with no big predators to control them. The population is able to grow to an unsustainable size, passing their carrying capacity the producers can provide. The trees are striped of bark and leaves as far as the animals can reach and the forest floor is absent of growth because of the grazing pressure from the primary consumers.