Native Bluegrasses Bothriochloa species and Dichanthium species
What do they look like ? Bluegrasses are strong , perennial grasses with blue-green leaves and soft seed heads with short , soft , dark brown-black awns ( seed casing ) projecting from the head . Awns are not as long as in black speargrass . Native Bothriochloa species leaves smell of turpentine when crushed and are related to the introduced Indian Couch / Bluegrass ( Bothriochloa pertusa ). Native Bluegrasses are prized by land managers because of their usefulness to stock .
Where do they live ? They occur throughout the region , but are more likely to be found on heavier clay or texture contrast soils ( clay-loams , clay-sands ) of box and ironbark woodlands .
What do they need to live , eat and breed ? Bluegrasses are considered to be 3P grasses ( Perennial , Productive and Palatable ), and also grazing ‘ decreasers ’. That is , they are selectively grazed by cattle and are thereby prone to decrease in abundance and yield when overgrazed .
When might I see them ? Bluegrasses are most obvious when seeding , usually between March and May . These perennial species flower and set seed in response to wet season rains . Usually , the blue-green new leaf growth is stimulated by the first wet season rains , and depending on the species , flower stalks are produced a few weeks later .
What management actions affect this species ? Native Bluegrasses are palatable and nutritious for stock . Overgrazing causes declines in Native Bluegrasses and favours more ‘ weedy ’ increaser native species ( e . g . Aristida spp .), and the introduced Indian Couch which is a heavy grazing increaser that replaces Native Bluegrasses . Wet season spelling and conservative grazing practices will enable these valuable species to persist . Managing fire can also be important for Native Bluegrasses . Occasional , early dry season fires are the least damaging . Conversely , repeated annual burning reduces the ability of the grasses to build biomass and reduces seed set .
How do they benefit the land I manage ? As well as their obvious value as cattle fodder , bluegrasses provide food and thick shelter for numerous ground-dwelling animals , especially native mammals such as dunnarts and bettongs . The thick , tufted growth habit of bluegrasses slows the passage of water across the landscape , reducing erosion and increasing infiltration . Bluegrasses also produce a large amount of leaf and stem mulch , further adding to soil health .
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