PLANT PROTECTION 1 – Pests, Diseases and Weeds

PLANT PROTECTION 1 – Pests, Diseases and Weeds
Description of some weeds species (contd)
Monocotyledons (narrowleaved weeds) – SEDGES. (contd)
(Family Cyperaceae)
MULLUMBIMBY COUCH (Cyperus brevifolius)
Type Persistent herbaceous perennial up to 15 cm
high. Resists close mowing. A true sedge not
a grass. Pest in lawns and occasionally
pasture.
Leaves Grass-like, shiny light green, linear, in three's.
Triangular stems. Pungent odour when
bruised.
Flowers Terminal, globular or cone-shaped knobs,
green to white when mature.
Seeds Seeds freely.
Roots Masses of fibrous roots developing from
creeping stolons with extensive shallow
rhizomes.
Spread By seed and by stolons and rhizomes.
Leaves, inflorescence and stolons
NUTGRASS (Cyperus rotundus)
Type Persistent perennial herb usually 20-50 cm
high, troublesome weed of cultivation.,
gardens and surrounds. Does not resist close
mowing as in golf and bowling greens.
Probably indigenous to Australia. A true
sedge not a grass. Noxious weed in SA; is
said to be the world's worst weed; it occurs as
a weed in at least 100 countries and is possibly
the gardener’s worst nightmare.
Leaves Grass-like, shiny dark green, linear, in three's.
Triangular stems.
Flowers Terminal umbels of feathery, grass-like,
brown flowers.
Seeds The ‘seed’ is three-angled and less than half
the length of the enclosing glume.
Roots A mass of deep rhizomes with underground
tubers up to 25 mm long attached which give
rise to shoots and rhizomes. Chains of up to
15 tubers develop.
Spread By seed and by rhizome roots with tubers
readily spread by cultivation, is the basis of its
troublesome nature.
Flowers, rhizomes and tubers
Weeds - Biology, classification and identification 425