Natural populations
Acacia boormanii occurs mainly in the upper catchment of the Snowy River, south from the Cooma district in New South Wales to the highlands of Victoria [1,2]. It has been widely cultivated in the ACT where is has become naturalised. Acacia boormanii is usually a shrub to 2 m tall but sometimes attains up to 4 m in height. It grows on rocky slopes and along creeks in sandy and gravelly soils [1,2].
Flowering and seeds
Acacia boormanii flowers during August to September: pods mature November-December [3]. Nicking or boiling the seeds in water for a minute at 100°C is required to induce germination.
Cultivation and uses
Acacia boormanii is a frost tolerant, nitrogen-fixing shrub with an ability to pioneer cold, degraded sites.
Key descriptors:
Climate parameters
Mean annual rainfall: 600-1250 mm
Rainfall distribution: pattern uniform or winter
Mean annual temperature: 10-17 °C
Mean max. temperature of the hottest month: 25-29 °C
Mean min. temperature of the coldest month: -1-2 °C
Frosts: greater than 20 per year
Frost intensity: light to moderate (0 to -5°C) or heavy (greater than -5°C)
Altitude: 400-800 metres
Tolerance of climate extremes
Drought: known to be moderately drought tolerant
Fire: killed by damaging fire
Frost: tolerates frosts in the 0° to -5°C range or tolerates heavy frosts colder than -5°C
Soil factors
Texture: clay loam, light to medium clay (35-50% clay), loam, sandy loam, sandy clay loam or sand
Soil pH reaction: acidic (less than 6.5) or neutral (6.5-7.5)
Soil depth: skeletal to shallow (less than 30 cm)
Drainage: well-drained
Salinity: non-saline
Tolerance of adverse soils
Extremes in pH: acidity
Extremes in texture: clayey or sand
Salinity: nil - sensitive to saline soils
Soil waterlogging tolerance: nil - sensitive to waterlogged soils
Biological traits under cultivation
Habit: evergreen, shrub less than 2 m tall, multi-stemmed from or near ground level or shrub or small tree less than 5 m tall
Longevity: short-lived less than 15 years
Growth rate: fast or moderate
Coppicing ability: vigorous, responds to pruning, pollarding
Erosion control potential: excellent for clayey sites or excellent for sandy sites
Root system: shallow and spreading, fixes nitrogen via root symbiot, forms root suckers
Shade tolerance: grows best in full sunlight
Wood density: low (less than 600 kg/cubic metre) or mod. to high (greater than 600 kg/cubic metre)
Carbon sequestration potential: low
Uses
Potential farm use: good ornamental attributes
Specialty products: pollen has value in apiculture
Urban use: good as an ornamental or amenity plant
Potentially undesirable attributes
Fire sensitivity: killed by severe fires (seeder)
Growth habit: mod. to strong propensity to root sucker, shallow roots may outcompete adjacent plants
Weediness: high potential based on its biology
References
[1] Maslin BR (2001) Acacia boormanii. Flora of Australia, 11A: 334.
[2] Tame T (1992) Acacias of New South Wales. Kangaroo Press, Sydney.
[3] Gunn BV (2001) Australian Tree Seed Centre Operations Manual. Internal Publication, CSIRO Australian Tree Seed Centre, ACT. [Online at http://www.ensisjv.com/Portals/0/atsc-opmanualcomplete.pdf Accessed March 2008]
Internet links
PlantNET National Herbarium of New South Wales: http://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&showsyn=&dist=&constat=&lvl=sp&name=Acacia~boormanii
World Wide Wattle: http://www.worldwidewattle.com/speciesgallery/