Coarse grasses in lawns
Fine turf can quickly become overrun by more vigorous 'weed' grasses.
Coarse grasses can invade turf, epecially where the sward suffers from compaction, drought or excessive mowing. In winter they are more common, as the fine grasses stop growing while these coarser, less desirable grasses continue to develop. Some fine grasses, such as fescues and bents, can also be 'burnt' in freezing weather, which checks their growth.
Control
Turf grasses start to grow strongly in March, when an application of a spring lawn fertiliser, high in nitrogen, will be beneficial. Mowing regularly also helps as the finer grasses are better adapted to being cut, while coarse grasses will be weakened. Light raking with a spring-tine rake to lift the coarser patches allows a better cut, but do not mow too low. There are no selective weedkillers that can be used against coarse grasses, but individual weed grasses can be removed by hand. For larger problem areas fork out the worst patches adding soil to re-establish the level and then re-seed with a fine lawn seed mix or returf in September.
Tony Dickerson