Crypsis
schoenoides
is a prostrate annual with erect flowering branches to 30cm.
The inflorescence is an elliptical to ovoid panicle to 4cm
long, produced in summer and autumn. It is a weed of
irrigated pastures and disturbed wetlands on the Swan
Coastal Plain. Native to North Africa and Eurasia.
Cynodon
dactylon (couch)
is a stoloniferous and rhizomatous prostrate perennial, to
several metres across, rooting at the nodes. The leaves are
bluish-green. The inflorescence of two to seven digitate,
purplish spikes of flowers is produced in late spring and
summer. It is widely planted as a lawn grass and it invades
wetlands and river edges in southern Western Australia. It
is native to the Kimberley and the tropics
worldwide.
Cynodon dactylon
, RR
Cynosurus
cristatus
(crested dog's tail) is a tufted perennial to 70cm. The
inflorescence is a dense, one-sided, spike-like panicle with
short awns, produced in spring. It is a weed of disturbed
ground and pastures in the south-west of Western Australia.
Native to Europe and SW Asia. C. echinatus (rough dog's tail) is an annual with a similar
inflorescence to the previous species, but with longer awns.
It flowers in spring and early summer and is a weed of
pastures, creeklines and disturbed woodlands from Perth to
Albany. Native to the Mediterranean.
Dactylis
glomerata
(cocksfoot) is a densely tufted perennial to 1.5m tall. The
inflorescence is dense and one-sided, with spikelets
clustered at the ends of branches. Flowers in late spring
and early summer. Introduced as a pasture grass for higher
rainfall areas, it now also occurs in disturbed creeklines,
roadsides and wasteland from Gingin to Albany. Native to
Europe.
Dactylis
glomerata
, PH
Dactyloctenium
aegyptium
(coast button grass) is a spreading annual to 70cm tall. The
inflorescence consists of three to nine terminal,
finger-like spikes that are produced during most of the
year. It is a scattered weed of river edges, vine forest and
disturbed ground throughout the Kimberley. Native to Africa.
D.
australe
(Durban grass) is a stoloniferous perennial to 80cm tall.
The inflorescence consists of two to five terminal, digitate
spikes that are produced in summer. Used as a lawn grass, it
has been recorded from disturbed sites in Perth. Native to
South Africa.
Dichanthium
aristatum
(Angleton grass) is a loosely-tufted perennial to 1m tall.
The inflorescence consists of two paired, brown spikes,
3-7cm long. It is spreading around Kununurra, flowering in
summer. A pasture grass from India.
Dactyloctenium
aegyptium
, RR
Digitaria
ciliaris
(summer grass) is an annual with spreading stems and erect
inflorescences 20-80cm tall. The inflorescence is composed
of 2 to 12 terminal, slender, digitate racemes. It is a very
common garden weed in southern Western Australia, flowering
in summer. In the Kimberley it is a weed of crops and
disturbed areas. Native to the tropics and subtropics.
D.
aequiglumis
has recently been recorded as a roadside weed on the
northern outskirts of Perth. Very similar to
D.
ciliaris,
it differs in minor characters of the inflorescence. Consult
a specialist text for exact identification. It flowers in
spring and summer and is a native of South America.
D.
didactyla
(Queensland blue) is a stoloniferous perennial to several
metres across, used as a lawn grass and spreading into
adjacent disturbed sites and swamps in the Perth area.
Flowers in summer. Native to the Canary Islands.
Digitaria
ciliaris
, RR
D. sanguinalis (crab grass) is an annual with creeping stems, 2-15cm tall. The inflorescence is erect, digitate, of 3 to 10 purple racemes, produced in summer. Very similar to D. ciliaris, it is a very common garden weed in southern Western Australia. Native to the Mediterranean. D. violascens is a spreading annual, 2-50cm tall. It occurs in disturbed areas near Perth and flowers in summer. Native to tropical America and Asia.
D.
sanguinalis
, PH
There are 12
species of Echinochloa (barnyard grasses) in Western Australia, and a
specialist text will be needed for exact identification.
E.
colona
(awnless barnyard grass) is a tufted annual, 20-90cm tall.
Flowers in summer and winter. It is a widespread weed of
creeks, swamps and irrigated crops in the Kimberley and
Pilbara. Native to Africa and Asia.
Echinochloa colona
, GK
E. crus-galli (barnyard grass) is an annual to 90cm tall. The inflorescence is an erect spike-like panicle of green flowers. It is common along drains in the Perth area and flowers in summer. (It is a major weed of rice, reducing yields up to 30 per cent - or even more, depending on density - and is ranked as one of the three worst weeds of tropical and temperate crops in the world.) Native to Europe.
E.
crus-galli
, RR
E. crus-pavonis (South American barnyard grass) is a tufted annual to 1.3m tall. The inflorescence is soft, green to purple, drooping at maturity. It is common along drains in the Perth area, flowering in summer. Native to tropical Africa and America.
E.
crus-pavonis
, RR
