Easily overlooked due to its small stature, field wood-rush is a common sight in the UK countryside and an important food plant for several species of moth. However, in gardens, its brown flowers and broad leaves can be considered unsightly by gardeners wanting a fine, manicured lawn.
Field wood-rush is a tufted, grass-like perennial with broad-bladed dark green leaves that are fringed with long, silky, white hairs. In March and April, it produces rounded clusters of dark brown flowers with conspicuous yellow anthers. These sit atop upright green stems and are most noticeable before lawn mowing begins. The flowers are followed by brown fruits containing three seeds. It grows to around 15cm (6in) high and often dies back by mid-summer. Underground, it produces fibrous roots and sometimes short rhizomes; overground it creeps by stolons (horizontal stems).
© Shutterstock4 / 4Flowers are followed by rounded, dark fruits containing seed1 / 4Silky, white hairs are clearly visible along the leaves of these young field wood-rush plants2 / 4Clusters of dark brown flowers are held above tufts of leaves © Shutterstock4 / 4Flowers are followed by rounded, dark fruits containing seed1 / 4Silky, white hairs are clearly visible along the leaves of these young field wood-rush plants2 / 4Clusters of dark brown flowers are held above tufts of leaves prevnextDid you know?Field wood-rush has some interesting common names. The appearance of its flowers in March and April gave rise to the name Good Friday grass, and in West Yorkshire they were used as a yearly sign to put cattle out to pasture. The shape and ‘sooty’ colour of its flowers have also given rise to the common names of ‘chimney sweeps’ and ‘sweep’s broom’.
Field wood-rush has some interesting common names. The appearance of its flowers in March and April gave rise to the name Good Friday grass, and in West Yorkshire they were used as a yearly sign to put cattle out to pasture. The shape and ‘sooty’ colour of its flowers have also given rise to the common names of ‘chimney sweeps’ and ‘sweep’s broom’.
Field wood-rush is a UK native perennial found among short grass in pastures and on downland, grassy banks and verges. It is a good plant for wildlife, with its leaves eaten by caterpillars of smoky wainscot, double line, broad-bordered yellow underwing and dotted fan-foot moths, as well as those of several species of micro-moth.
© ShutterstockCaterpillars of the smoky wainscot moth feed on field wood-rush leaves As field wood-rush thrives in damp, acid soil conditions and tolerates full shade and foot traffic, it makes a useful lawn alternative (alongside other species) in gardens where lawn grasses struggle. However, gardeners wishing to maintain a fine, formal lawn are likely to consider field wood-rush as a weed.
What is a weed?The term ‘weed’ describes a plant that is growing where it isn’t wanted. Weeds usually thrive in average garden conditions, reproducing and spreading easily. It is up to you to decide what you call a weed and what you choose to retain or remove.
The term ‘weed’ describes a plant that is growing where it isn’t wanted. Weeds usually thrive in average garden conditions, reproducing and spreading easily. It is up to you to decide what you call a weed and what you choose to retain or remove.
Field wood-rush spreads by seed and stolons (horizontal above-ground stems). Its seeds are dispersed by ants (see below) and the wind, so you could find seedlings appearing some distance from the parent plant. However, in lawns, regular mowing tends to remove field wood-rush flowers before they can set seed.
Did you know?Ants are attracted to a fleshy, fat-rich appendage on the outside of the seed coat called an elaiosome. Ants carry ripe seed into their nests and feed the elaiosome to their larvae before depositing the seed in the rich soil of their waste piles, where it germinates.The main method of spread in lawns is by creeping stolons, and a single plant can work its way slowly through a lawn if allowed to. This is good news if you are trying to establish a species-rich lawn and support your garden wildlife but may not be so welcome if you want an immaculate, fine lawn.
Ants are attracted to a fleshy, fat-rich appendage on the outside of the seed coat called an elaiosome. Ants carry ripe seed into their nests and feed the elaiosome to their larvae before depositing the seed in the rich soil of their waste piles, where it germinates.
No – allowing field wood-rush to grow in a species-rich lawn or wild area, or on a grassy bank, is a great way to boost the biodiversity of your garden and support your garden wildlife. However, if you prefer a perfectly manicured lawn, you’ll probably want to remove it.
© ShutterstockField wood-rush grows well alongside other plants in grassy areas on damp, acid soil
If you have field wood-rush growing in your lawn where it is not wanted, there are a few ways to remove it:
Don’t add field wood-rush seedheads, rhizomes or stolons to your home compost bin, as it may not reach high enough temperatures to kill them. Instead, put them in your council green waste recycling bin or take them to your local recycling site.
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