Herbivorous mammals devour many species bodily, while some uproot and devour the buried tubers.
In animals, it is the eggs or the very young that suffer most from their various enemies; in plants, the tender seedlings when they first appear above the ground.

To illustrate this latter point Mr.Darwin cleared and dug a piece of ground three feet long and two feet wide, and then marked all the seedlings of weeds and other plants which came up, noting what became of them.

The total number was 357, and out of these no less than 295 were destroyed by slugs and insects.

The direct strife of plant with plant is almost equally fatal when the stronger are allowed to smother the weaker.

When turf is mown or closely browsed by animals, a number of strong and weak plants live together, because none are allowed to grow much beyond the rest; but Mr.Darwin found that when the plants which compose such turf are allowed to grow up freely, the stronger kill the weaker.