PLANT PROTECTION 1 – Pests, Diseases and Weeds

PLANT PROTECTION 1 – Pests, Diseases and Weeds
Description of some weeds species (contd)
Monocotyledons (narrowleaved weeds) – GRASS WEEDS.
(Family Poaceae)
COUCH, BERMUDA GRASS (Cynodon dactylon)
Type
Leaves
Sometimes sown as lawn grass, recreational
turf. Perennial grass weed common in all
states. Known to cause cyanic acid poisoning
under some conditions but generally can be
eaten without damage. Various turfgrass
cultivars are used in the turf industry.
Prostrate rhizomes and stolons, perennial grass
with hairs arranged in 2 rows on opposite sides
of the stem. Commonly some specimens have
sparse hairs on the top of the sheath and
blades.
Flowers The inflorescence is finger-like. Spikelets are
single-flowered and small. They occur
in 2 rows on the under side of flattened main
axis of the spike.
Seeds
Roots
Spread
Only produces seed heads in neglected areas.
Seed heads often infected with a smut disease
(Ustilago sp.).
Stolons root readily at nodes.
By seed, rhizomes and stolons and by cut-up
pieces of rhizomes and stolons during
cultivation.
Leaves, inflorescences, stolons,
rhizomes and roots
PASPALUM (Paspalum dilatatum)
Type Perennial summer growing grass which can
grow up to 1 meter in favorable conditions.
Can be a useful pasture plant. Naturalized in
all states, often troublesome in gardens
especially in lawns. Will crowd out clover and
become dominant.
Leaves Rolled in bud leaf, medium texture, gray
green, long parchment ligule.
Flowers Spikelets of 3-7 arms. Inflorescence is sticky
to touch.
Seeds Seed heads may be infected with paspalum
ergot (Claviceps paspali).
Roots Deep, fibrous from strong short woody stolons
and rhizomes.
Spread By seed, by the growing of stolons and
rhizomes and by cut-up pieces of stolons or
rhizomes spread during cultivation.
Leaves, flowers and roots
Major world weed especially in perennial
crops.
Weeds - Biology, classification and identification 423