Nutrient Excess

An oversupply in the availability or presence of a nutrient which is not needed by a plant. An excess may or may not cause any observable detriment to a plant, but where high and excessive amounts of nutrients within a soil can create conditions which are more favourable to weeds and weed grasses, making them more competitive than desirable grasses. For example, high phosphorus content can encourage clover and annual meadow grass to the detriment of perennial ryegrass in winter games pitches, or red fescue and bents in fine turf situations.