From Seed to Seed:
Plant Science for K-8 Educators

Competition

Competition in nature. Perhaps you have walked in a woodland, and, rounding a bend, come upon a patch of blooming lady's slippers (lucky you!) or another favorite wildflower. Why were the lady's slippers flourishing there, but 20 feet away there were none to be seen? Every individual species of plant has a particular set of environmental conditions under which it will thrive; in other words, to which it is best adapted. The characteristics of the environment in which an organism is best suited to live is called its niche. Perhaps the rich, moist soil and dappled light combined to provide just the right niche for the lady's slippers. Twenty feet away, the soil was drier, and the sun brighter, and these conditions better suited a different plant.

On every patch of bare ground, plants compete intensely to colonize that open space. The plants that are best adapted to all of the particulars of that bare spot-the plants that best fit that niche-will be the most likely to succeed in filling it. Of course the niches of plants overlap; many different plants could grow in that spot. And if resources are plentiful, more than one plant can occupy a niche for a while. But over time, the competition among the plants for light, water, nutrients, and space-along with their tolerance of physical factors such as temperature and humidity extremes-will determine which species will be "victorious."

This all sounds pretty theoretical, so let's bring it closer to home.