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Scent in plants often consists of volatile compounds that can spread through air and soil to influence neighbors. A key use of these chemicals is allelopathy—they can suppress the germination or growth of nearby plants, reducing competition for light, water, and nutrients. This gives the emitting plant a better chance to thrive in crowded environments, which is why scent is important for this purpose. While scents can also attract pollinators or defend against herbivores, the direct advantage of hindering competitors explains why scent is especially significant. For example, juglone released by black walnut roots can inhibit nearby plants, illustrating how scent-based chemicals help plants compete.