First, the leaf blade elongates and is quickly followed by elongation of the sheath and then the internode. The shorter and later internode elongation allows the meristematic tissue to be retained low and near the soil surface while the leaves and sheaths grow well above this level. Thus, defoliation by mowing or grazing removes the leaves and not the meristem. The tiller may be defoliated, but it will continue to grow and produce foliage. Timing of defoliation does not appear to affect the emergence of other tillers, although the number of leaves may be reduced.
Some studies indicate that defoliation increases tiller numbers.
These plants are found in late-successional sites that were disturbed over 50 years ago. Kentucky bluegrass has the potential to invade and modify existing communities and poses a threat to the prairie vegetation. A limited number of control options exist for Kentucky bluegrass. Control methods for this species have been primarily chemical and cultural. An important consideration in controlling these species is that the seeds have the potential to remain viable in the seed bank for only about 2 years, however, plants readily spread by tillers and rhizomes.