Weed Identification
COMMON GRASS WEEDS
Winter Grass
Wintergrass seed germinates in autumn. The plants grow actively from late Autumn through to late Spring, seeding throughout Winter and Spring. Treatment: Can be treated with a pre-emergent spray throughout Autumn and Winter or post-emergent in Spring. |
Crabgrass
An annual weed with fibrous roots and clusters of soft stems which grow close to the ground. Germinates in Spring/Summer. Treatment: Can be treated with a pre-emergent spray in Spring before seed germination occurs, and post-emergent in couch species throughout Summer/Autumn. |
Nutgrass
Invasive grass growing actively throughout Spring/Summer/Autumn. Treatment: Spraying is most effective in warmest months of the year. |
Guildford Grass or Onion Grass
Germinates in late Autumn from a brown bulb or small brown seed. Firm, shiny, grass-like leaves grow actively through Winter and it flowers in Spring. Treatment: Controlled by spraying when weeds are actively growing, preferably before flowering. |
COMMON BROADLEAF WEEDS
White Clover
A perennial plant with white flowers in Spring which attract bees. The flowers produce seed that can remain viable in the soil for many years. Treatment: Controlled by spraying actively growing weeds in Winter/Spring. |
Bindii/Jo-Jo
An annual weed that establishes from seed in Autumn, grows actively through Winter and flowers in Spring. Treatment: Control needs to be timed to prevent seeding in Spring as it produces burrs with sharp spines. |
Capeweed
An annual weed which establishes from seed in Autumn, grows actively through Winter and flowers in Spring. Treatment: Controlled by spraying actively growing weeds. |
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Creeping Oxalis
A perennial weed that establishes from seed. Very persistent in low cut turf due to the stoloniferous growing habit. Treatment: Programme should include a pre-emergent spray plus spraying actively growing weeds. |
Onion Weed
An erect annual, biennial or perennial plant up to 30cm high, reproducing from seed or bulb. Treatment: Controlled by spraying when weeds are actively growing, preferably before flowering. |
Plantain
A commonly occurring perennial weed that grows from a rosette which produces new leaves and seed heads. Treatment: Controlled by spraying actively growing weeds. |
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Cat’s Ear (Flatweed)
Mature plant is semi-erect up to 30cm. Deeply lobed leaves with yellow flowers. Also known as flatweed. Treatment: Controlled by spraying actively growing weeds. |
Fleabane
An annual weed which, if left untreated, can shoot a seed head to over a metre high. Treatment: Controlled by spraying actively growing weeds, preferably before flowering as seed head can become tall and woody. |
Cudweed
Flat, dense weed which can shoot a hairy seed head up to a metre if left untreated. Mature plants can ‘choke’ grass underneath and leave pockmarks or divots in lawn surfaces once removed. Treatment: Controlled by spraying actively growing weeds, preferably prior to 4 or 5 leaf stage. |
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Creeping Buttercup
Erect, creeping, flowering perennial weed, sometimes referred to as ‘pop’ or ‘flick’ weed as seeds ‘pop’ off flowers when disturbed. Treatment: Controlled by spraying actively growing weeds as early in the cool season as possible to avoid seed-set. |
Chickweed
A delicate, erect annual weed which protrudes above the lawn canopy. Treatment: Controlled by spraying actively growing weeds. |
Carrotweed
Similar in appearance to Bindii; carries no spike-forming flower, just a small yellow-lobed flower on the end of a 40—50mm shoot. Generally forms earlier in the season than Bindii. Treatment: Controlled by spraying actively growing weeds. |
INSECT PESTS
African Black Beetle
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Lawn Armyworm
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Sod Webworm
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DISEASES
Dollar Spot
Small (4-5cm) circular sunken patches that can join up if left untreated. Occurrence: First appears as mycellium (cottony thread). Generally occurs at 15-30 degrees Celsius with high humidity or dew, and low nitrogen levels in turf. |
Brown Patch
Rapid onset of ’smoke ring’ patches within a period of less than a week. Can be from 5cm up to 1m in size. Occurrence: Onset is from October through to mid-May with moist, warm conditions favouring development. |
Pythium Blight
Begins as circular spots with a light brown water soaked appearance. Can feel slimy and affect large areas of turf quickly. Occurrence: Warm nights (+20 degrees Celsius) and warm days especially with soft growth from nitrogen application. |
Spring Dead Spot
Circular patches appear late Autumn/Winter as lawn growth declines. These patches can be 10—15cm across in 1st year, increasing to 15—40cm in subsequent years if left untreated. Patches may get larger than this. Occurrence: Late Autumn/Winter, with recovery evident throughout hottest months. |
Fusarium Patch
A small circular patch with a distinct smoke ring apparent in winter. May show a pink ring with a white centre. Occurrence: Prevalent in cool conditions (0-8 degrees Celsius) in turf with high nitrogen levels. |
Helminthosporium Complex
Causes reddish-brown to purplish-black spots on leaves and stems which spread quickly. Leads to turf dessication. Occurrence: Wet conditions with high humidity between 3-30 degrees Celsius. |
Photographs courtesy of Bayer Environmental Science.




























