Quick Facts

Quick facts

• Goatgrasses (Aegilops species) are winter-growing annual grasses that are potential weeds of cereal crops in Australia.
• Goatgrasses are not yet naturalised in Australia.
• The similarities of Jointed Goatgrass to Wheat make it highly competitive, and Wheat seed contaminated with Jointed Goatgrass seed is difficult to detect and separate.
• The seeds of some species (e.g. Barbed Goatgrass, A. triuncialis) can cause mechanical injury to livestock.

What Does It Look Like?

What is it?

Goatgrasses (Aegilops spp.) are winter-growing annual grasses with flowering stems (culms) growing 14–80 cm in height. The stems are usually hairless with 1–5 nodes (points where leaves arise). The leaf blades are flattened, 1.5–10 mm wide, spearhead shaped, and spreading. Membranous structures (ligules) are present at the base of the leaf blade, have an abrupt blunt tip and are 0.2–0.8 mm long.

The flower heads (inflorescences) are spike-like, occur at the tip of the flowering stems, and have 2–13 spikelets. The spikelets are solitary at each node and can be pressed against the stem (appressed) or spreading. Fertile spikelets are 5–15 mm long each with 2–7 florets. The glumes (outer bracts of the spikelet) are ovate (egg-shaped) to rectangular, rounded at the back, with a rough or hairy surface (Barkworth 1993; Saufferer 2008).

Jointed Goatgrass (Aegilops cylindrica) is the most problematic Aegilops species, particularly in North America. A number of other Aegliops species are also considered to be weedy in North America (Encycloweedia 2008).

For further information and assistance with identification of Goatgrasses, contact the herbarium in your state or territory.

Flower colour

Yellow, Red, Orange, Green

Growth form (weed type/habit)

Grass

Where it currently grows? Preferred habitat

Goatgrasses are potential weeds of cereal crops, grasslands, pastures and roadsides in temperate and sub-tropical regions in Australia (Navie 2004). They prefer dry sites (Encycloweedia 2008) and can grow in similar habitats to wheat (Agriculture Western Australia 2006).

Are there similar species?

Goatgrasses are closely related to Wheat (Triticum aestivum). Jointed Goatgrass, the most common of these species in cropping situations, can be distinguished from wheat by the presence of evenly spaced hairs along the edges of the leaf blades and by slender cylindrical flower-heads that have a jointed appearance (Navie 2004).

Three commonly weedy Aegilops species can generally be distinguished from one another on the basis of spike (inflorescence) length, the number of spikelets per spike, and awn length. Jointed Goatgrass has spikes 2–12 cm long, 3–12 spikelets per spike, the terminal spikelet have a single, 4–5 cm long, awn on the lemma (the lower of 2 bracts). Ovate Goatgrass has spikes 1–3 cm long, 2–4 spikelets per spike and the upper spikelets have 3 short lemma awns. Barbed Goatgrass has spikes 2–6 cm long, 2–6 spikelets per spike and the upper spikelets are 3-awned, with the glume awns 4–8 cm long (Encycloweedia 2008).

Why Is It A Weed?

What are its impacts?

Agriculture: In North America, Jointed Goatgrass is a problematic weed of winter wheat crops due to its similarities to wheat in appearance, seed size, growth requirements and patterns, and genetics (NAPPO 2003). Because of these similarities, Jointed Goatgrass is difficult to selectively control (Agriculture Western Australia 2006). This species is highly competitive with wheat thus significantly reducing yields (NAPPO 2003). Its seeds can also contaminate grain (NAPPO 2003; WSNWCB 2008). The similar seed size of Jointed Goatgrass makes it difficult to identify contamination, and causes difficulty in separation (NAPPO 2003). Jointed Goatgrass is known to hybridise with wheat and the hybrid plants display spikelets with the morphology of both species. The seed produced by hybrids is usually sterile (WSNWCB 2008).

Barbed Goatgrass can cause mechanical injury to livestock (Encycloweedia 2008).

How does it spread?

Goatgrasses reproduce by seeds that are similar to wheat. The seed of Jointed Goatgrass, which is a common weed of wheat crops in some areas, can be spread readily by farm machinery and can contaminate agricultural produce (Navie 2004).

What is its history in Australia?

The seed of Goatgrass was probably brought into the country for plant breeding purposes. There are no known naturalised population of Goatgrass in Australia (Navie 2004).

How To Manage It?

Best practice management

Prevention: Preventing seed dispersal is important in the control of Goatgrasses, as once established they can be difficult to control. The barbed seeds can attach to fur or wool of livestock, therefore grazing animals should be removed from infested areas before plants reach maturity and flower. Feeding contaminated grain to livestock can also increase the spread of Goatgrasses as the seeds of Jointed Goatgrass are able to remain viable even after passing through the gut. Certified seed should be used to avoid planting Goatgrasses (Encycloweedia 2008).

Non-chemical control: Mechanical control such as mowing can be used to reduce seed production. Mowing must be conducted after flowering and before seeding. Early mowing may result in new growth, and late mowing may increase the spread of seeds (Encycloweedia 2008). As Goatgrasses generally mature later than native annual grass species, burning can be used in non-cropping situations as an effective control method without disrupting annual grass seed production (Encycloweedia 2008).

Chemical control: There are currently no known selective herbicides for Goatgrasses in cropping situations (Encycloweedia 2008), but non-selective herbicides are effective for smaller infestation (WSNWCB 2008).

Please see the Australian Pesticides and Veterinary Medicines Authority for chemical information http://www.apvma.gov.au 

Does it have a biological control agent?

NO

When does it grow? (lifecycle/growth calendar)

Goatgrasses are winter annuals that flower in late spring to early summer, with seed generally germinating in mid-autumn (NAPPO 2003). The seed of some Aegilops species can remain dormant and viable for 2 or more years in the soil if conditions for germination are not favourable (Encycloweedia 2008) and some species produce abundant seeds. For instance, Jointed Goatgrass can produce up to 300 seeds per plant when growing with wheat, but individual plants can produce up to 3,000 seeds without competition. Like winter wheat, flowering in Jointed Goatgrass and some other Aegilops species is stimulated by cold temperatures (Grass Weeds in Wheat 2008; Encycloweedia 2008).

Where Is It Found?

Which states and territories is it found?

What areas within states and territories is it found?

Goatgrasses are not known to be naturalised in Australia, although seed of Jointed Goatgrass (A. cylindrica) has been used for plant breeding purposes and has possibly escaped cultivation in eastern Australia (Navie 2004). Jointed Goatgrass is thought to be well-suited to Australian wheat growing areas, especially in Western Australia, South Australia and Victoria (Agriculture Western Australia 2006).

Where does it originate?

Goatgrasses are native to the Mediterranean regions, central Asia and the Canary Islands (Saufferer 2008).

National And State Weed Listings

Is it a Weed of National Significance (WONS)?

NO

Where is it a declared weed?

WA

Government weed strategies and lists – Weeds Australia

Is it on the National Alert List for Environmental Weeds?

NO

Government weed strategies and lists – Weeds Australia

Is it on the Agricultural Sleeper List?

NO

Government weed strategies and lists – Weeds Australia

Names And Taxonomy

Main scientific name

Aegilops spp.

Other scientific names (synonyms)?

Does it have other known common name(s)?

Goat-grasses