Interim Recovery Plan No. 147
Rebecca Evans, Sarah Barrett, Gillian Stack and Andrew Brown
Department of Conservation and Land Management, WA, 2003
Andersonia axilliflora was initially named Sphincterostoma axilliforum in 1859 by Stschegl in Bulletin de la Societe Impriale des Naturalistes de Moscou 32(1) 22 from Drummond's collection V. No. 301. However, in 1917 it was placed in Andersonia by Druce.
Surveys of the Stirling Range by staff from DCLM, Botanic Garden and Parks Authority (BGPA) and others have resulted in the discovery of eleven populations of Andersonia axilliflora, on peaks in the eastern section of the Stirling Range.
The Eastern Peak Route, now known as the Ridge Walk, was developed in the 1930s and runs from Bluff Knoll to Ellen Peak. The alignment of this route has been assessed regarding possible effects on threatened species and communities and has been found to be of no current threat.
Fire has had a major impact on the flora of the Stirling Range including Andersonia axilliflora. There is an anecdotal report of a fire in the 1950s, and records of major fires in the eastern Stirling Range in February 1972, April 1991 and October 2000. The intense fire of 1991 burnt most populations of A. axilliflora and a large portion of the eastern Stirling Range. Although only a small number of adult plants escaped the fire, seedlings were observed during the following year. Pre-fire adult plants exceeded 1 m in height; however, after eight years post-fire many seedlings ranged from 20-40 cm in height and had not flowered. In 1999 there were some 700+ juvenile plants and less than 200 mature plants. The 2000 fire burnt many populations again, further taxing the soil seed bank. All populations are under threat from dieback (Phytophthora cinnamomi), which affects both mature plants and seedlings. In 2002, there were approximately 440 mature plants and 660 juveniles.
A three year Interim Recovery Plan (IRP) prepared for Andersonia axilliflora in May 1999 will be replaced by this revised 5 year IRP. A draft IRP has been written by Sarah Barrett ¹ for the Critically Endangered ecological community, 'Montane thicket and heath of the South-West Botanical Province above approximately 900 m above sea level' (hereafter abbreviated to 'Eastern Stirling Range Montane Heath and Thicket Community'), of which A. axilliflora is the key indicator species. The threatened ecological community (TEC) IRP outlines recovery actions for many of the same processes that are threatening A. axilliflora and both IRPs should be taken into account when management actions are implemented.
Andersonia axilliflora is the tallest growing species in the genus. It is a sturdy shrub to 3 m with erect branchlets and distinctive crowded triangular leaves. The leaves are broad at the base, where they clasp the stem, and taper to a point. The floral leaves at the ends of the branches are creamy white, and extend beyond the thirty or so hidden flowers. Each cream flower, about 1 cm long, is enclosed in stiff calyx lobes, which also taper to a point. (Brown et al. 1998).
Andersonia axilliflora occurs at high altitudes in the eastern section of the Stirling Range between Mt Success and Ellen Peak. The Stirling Range is approximately 90 km north of Albany, near Western Australia's southern coastline. The species has been identified as the key indicator species for the Critically Endangered Eastern Stirling Range Montane Heath and Thicket Community (Barrett 1999).
Habitat is low, dense heath and scrub on rocky shallow soil over schist. The community is also characterized by species such as Kunzea montana, Beaufortia anisandra, Sphenotoma sp. Stirling Range, Andersonia echinocephala, several Darwinia species, Banksia solandri, Calothamnus crassus and Dryandra concinna (Barrett 1999).
Several other threatened flora species that also occur within the community include Dryandra montana, Sphenotoma drummondii, Darwinia collina, D. squarrosa, Banksia brownii and Persoonia micranthera (Barrett 1999).
¹ Sarah Barrett, Conservation Officer , DCLM's Albany Work Centre
A. axilliflora is known to be highly susceptible to dieback (Phytophthora cinnamomi), ranking 9 on a scale of 1 to 10 where 7 is considered a significant risk (Keighery 1988). Most populations occur in areas known to be infected with dieback and laboratory testing has suggested that the species is highly susceptible to the disease.
Fire kills adult plants of this species. However, the death of mature plants is compensated for as it also stimulates the germination of soil-stored seed. Frequent fire, on the other hand, may result in the decline of populations by killing seedlings before they reach maturity.
It appears that this species, like several other montane species (e.g. Persoonia micranthera), is slow-growing and takes a relatively long time to reach reproductive maturity. Mature plants grow up to 3 m tall; however, after eight years post-fire most seedlings ranged from 20 to 40 cm tall. Several plants at Population 3 started to flower for the first time 9 years after the area was burnt in the 1991 fire.
The level of germination seen after the 2000 fire suggests that the seed may remain viable in the soil for very long periods and that seed has dormancy mechanisms or physical attributes that prevent all seed germinating in response to one fire event. It is likely that additional information would be gained following study of flower and fruit production, on-plant and soil seed banks and seed longevity in the soil (at present, flowering is being measured and assessed annually).
A study of the biology and conservation of Western Australian Epacridaceae states that the genus Andersonia is endemic to Western Australia and has the greatest species diversity in the Albany region (Keighery 1996). Two Andersonia species are listed as being pollinated by birds but Keighery suggests that insects, possibly moths and butterflies, pollinate most species. A beetle has been observed pollinating at Population 1. Seed is probably dispersed by gravity or wind (Keighery 1996).
Andersonia axilliflora was declared as Rare Flora in October 1996 and ranked as Critically Endangered (CR) in November 1998. The species currently meets World Conservation Union (IUCN, 2000) Red List Category 'CR' under criteria A2e as all populations are threatened with Phytophthora and drought death and it is estimated that there will be a decline of 80% in the next three generations. The main threats are Phytophthora, wildfire and damage through recreational use.
- Phytophthora cinnamomi is a major threat to all known populations of the species. Andersonia axilliflora is highly susceptible to the pathogen, which kills susceptible plants by invading their root system and severely reducing their ability to take in water and nutrients. Many other species in the community in which A. axilliflora occurs are also affected by the disease. In relatively undisturbed habitat Phytophthora spreads through root-to-root contact and through free water flow. Although it spreads most quickly downhill it is capable of moving uphill. It also spreads through movement of infected soil, by foot (see Recreational Use) or by vehicles during firebreak and track use. P. cinnamomi thrives best in mild moist conditions such as that produced by spring, autumn or summer rainfall. The interactions of fire and dieback are not completely understood but field observations suggest that fire in areas where the disease is already present increases susceptibility (unpublished observation S. Barrett).
- Wildfire may adversely affect the long-term viability of Andersonia axilliflora populations. During a 1991 fire most adult plants were killed and seedling survival rates were low with approximately 50% of individuals dying from P. cinnamomi infection (unpublished observation S. Barrett). Seedlings take a minimum of 9 years to mature (become reproductive) with most plants assessed at Populations 1 yet to flower 11 years post-fire. Another major fire burnt many populations in October 2000, killing most juveniles in Populations 1, 3, 5, 6, 7, 8, 9, 10 and 11. However, there has since been germination of seed in Populations 1and 9 showing that there was still viable seed persisting in the soil. If a third major fire occurs before seed is produced in significant quantities, the soil seed store will be seriously depleted.
- Recreational Use of the Stirling Range is high. Uses include hiking, camping and rock climbing, all of which may result in disease introduction/movement, trampling and secondary track formation. A major focus for recreational use in the eastern Stirling Range is the Ridge Walk which runs from Ellen Peak to Bluff Knoll. This walk is usually completed in two to three days thus requiring camping in the area overnight. Most visitors do not tend to deviate from the Walk but assessment, monitoring and regulation of visitor numbers may be necessary to ensure Andersonia axilliflora populations and high priority areas in the Montane Heath and Thicket Community are not compromised by visitation, e.g. camping and toileting.
- Grazing by herbivores is having a minor impact on the habitat and some individual Andersonia axilliflora plants but the identity of the herbivore is unclear (personal communication S. Barrett).
|Pop. No. & Location||Land status||Year / No. Plants||Fire History||Phosphite||Condition||Threats|
|1. Stirling Range||National Park||1999 20 (500) 
2001 100+ (c. 600) [many]
2003 250+ (500+)
|Apr & May 1997||Moderate||P. cinnamomi, fire, recreational use|
|2ab. Stirling Range||National Park||1999 (90)
2001 5 (15)
|Not 1991 Not 2000||Apr 1998||Poor||P. cinnamomi, fire, recreational use, grazing|
|3ab Stirling Range||National Park||1998 (100)
|Oct 2000||Poor||P. cinnamomi, fire, recreational use|
|4a-e Stirling Range||National Park||2000 150 (150)
2003 50 
|Apr & May 1997||Moderate||P. cinnamomi, fire, recreational use|
|5. Stirling Range||National Park||2000 20 
2003 3 (4)
Mar & Apr 2001
|Poor||P. cinnamomi, fire, recreational use|
|6. Stirling Range||National Park||1997 75 
2002 0 (30)
|C. half 1991
|Moderate||P. cinnamomi, fire, recreational use|
|7. Stirling Range||National Park||1997 20+||Apr 1991||Moderate||P. cinnamomi, fire, recreational use|
|8. Stirling Range||National Park||1997 50+||Apr 1991||Moderate||P. cinnamomi, fire, recreational use|
|9a. Stirling Range||National Park||2000 0 (300) 
2002 0 (100)*
2003 0 (100)*
|Apr 1998||Poor||P. cinnamomi, fire, recreational use|
|9b. Stirling Range||National Park||See 9a above||Apr 1991||Apr 1998||Poor||P. cinnamomi, fire, recreational use|
|10. Stirling Range||National Park||1999 15 (250)
2002 11 (5)
|Not 2000||Apr & May 1997||Moderate||P. cinnamomi, fire, recreational use|
|11. Stirling Range||National Park||2000 0 (24) ||Apr 1991||Poor||P. cinnamomi, fire, recreational use|
Number in ( ) = number of juveniles. Number in [ ]= number of dead plants. * = total for subpopulations combined.
Note: It is likely that the eleven currently recognised populations previously occurred as
three larger populations that have become fragmented as a result of dieback and fire.