Mouse-ear chickweed identification and control

Mouse-ear chickweed (Cerastium vulgatum)

A short-lived perennial weed very common in intensively managed lawns and grass areas.  Resembles common chickweed but has a darker leaf and is covered in noticeable hairs.

Appearance

The dark green leaves are opposite, oval or lanceolate in shape and 10-20 mm long.  They are also covered in soft hairs.

Flowers appear between April and November and are white in colour.  Each flower is approximately 6mm in diameter and has 5 petals that are deeply lobed, often giving the appearance of 10 petals.

Growth habit

Mouse-ear forms a dense mat, tolerant of close-mowing.  It has a fibrous root system and new plants will grow from new roots at the nodes as well as from seed.

Conditions that favour its development

Thrives in cool, shade where drainage is poor but can also tolerate hot, dry conditions.  Can spread very quickly if conditions are favourable.

Cultural control

Ensure that turf is strong and healthy, avoiding bare areas that provide opportunity for weeds to invade:

• Mow regularly and at a sensible cutting height, appropriate to the grass species and growing conditions; apply fertiliser at regular intervals through the growing season, as the turf requires, to support healthy growth and good root development.
• Water only if required. Over-watering will weaken the turf and keep the soil moist to encourage the development of the mouse-ear plants.
• Maintain good surface drainage, using a combination of aeration and top dressing to maximise surface infiltration and encourage good breakdown of water retentive organic matter.
• Reduce shade by pruning or removing surrounding vegetation. Plants positioned on the southern and eastern horizons will impact most on sunlight levels and should be tackled first.
• Remove small plants by hand using a knife or similar tool.
• Mow regularly to help keep flower production and therefore seed to a minimum.

Chemical control

Most of the selective herbicides on the market will tackle Mouse-ear chickweed effectively with a single application but a second application should be applied if required.

Always apply when the grass and weed are growing strongly (usually between April and September) to optimise effectiveness of the treatment.