Indicative distribution
The areas shown in pink and/purple are the sub-regions where the species or community is known or predicted to occur. They may not occur thoughout the sub-region but may be restricted to certain areas.
(
click here to see geographic restrictions).
The information presented in this map is only indicative and may contain errors and omissions.
Scientific name: Zieria buxijugum
Gazetted date:
31 Jul 2009
Profile last updated:
22 Feb 2024
Description
The Box Range Zieria is an erect shrub that rarely grows to more than 2.5 m high, but some individuals have attained 3.5 m in height. The leaves are distinctive, with each leaf being comprised of three spreading leaflets (trifoliate) and with the central leaflet being slightly longer than outside leaflet. The leaflets are dull green-grey above and pale green beneath, are covered in a dense, velvety layer of hairs and are strongly aromatic when crushed. The flowers are white, have four petals and are arranged in clusters of up to 28 towards the ends of the branchlets. Flowering is primarily in September but some plants may commence as early as late July. The seed pod is a warty four-chambered capsule. Each capsule contains a single ovoid dark brown seed about 1 mm in diameter.
Distribution
The Box Range Zieria is known from only one population which was about 125 plants in June 2015. This represents a significant increase since 1987 when only 68 heavily browsed plants were recorded. The population occupies an area of about 0.25 hectares on private property about 15 km west of Pambula on the NSW far south coast.
Habitat and ecology
- Occurs near the summit of a steep rhyolite rocky outcrop on a slope with an easterly aspect.
- The site has much exposed rock with pockets of skeletal humus rich loam amongst the rocks and on rock ledges.
- Grows in a shrub plant community dominated by Melaleuca armillaris (Bracelet Honey Myrtle) and below the outcrop is open forest dominated by Eucalyptus sieberi (Silvertop Ash). The groundcover is very sparse and includes scattered plants of Lepidosperma urophorum (Rapier Saw Sedge), Platysace lanceolata (Shrubby Platysace), Plectranthus parviflorus (Cockspur Flower) and Dendrobium speciosum (Rock Orchid).
- The site appears to be a fire refugia and it is thus expected that the Box Range Zieria would be an obligate seeder (i.e. it is likely to be killed by fire and regenerate only from seed).
- Mature plants flower prolifically in a favourable season and individuals can produce large quantities (100s) of seed. Seedling establishment has been observed to occur periodically over the last 20 years, although most have been so severely browsed by wallabies that they have died.
- The life span of individuals is not known with certainty, but most plants protected by wire mesh cages in 2001 were still looking healthy in June 2015, 14 years later.
- Because of the rocky nature of the site the vegetation, including the Zieria, is particularly prone to drought stress. The death of many smaller Box Range Zieria plants and a large number of Braclet Honey Myrtle plants at the site was observed during the lengthy drought which commenced in the early 2000s.
Regional distribution and habitat
Click on a region below to view detailed distribution, habitat and vegetation information.
Threats
- The small population size (approximately 125 plants) occupying a small area (approximately 0.25 hectares) makes this species highly susceptible to extinction through events such as wildfire, drought and frequent browsing by native and non-native animals.
- Since mid-1986, ongoing and severe browsing damage has been inflicted by wallabies. Monitoring has shown that most individual plants located outside wire mesh guards have eventually been killed. Fortunately, the population occurs on a very steep rocky site and is unlikely to be subject to stock grazing.
- The site is on private land. The current owners are highly supportive of protecting this species, however there is uncertainty that future owners of the property would be as sympathetic to the protection of the species.
- The species occurs in a shrub community in a rocky habitat that appears to be rarely impacted by fire. It is supected that if the site were impacted by a severe fire event that the Zieria plants would be killed and that the species would have to regenerate from seed. This would expose the regeneration to the impacts of post-fire browsing by wallabies, as most new individuals are unlikely to be protected by the existing plant guards.
Recovery strategies
A targeted strategy for managing this species has been developed under the Saving Our Species program; click
here for details. For more information on the Saving Our Species program click
here
Activities to assist this species
- Individuals of the species have been propagated from cuttings at Botanic Gardens in Canberra and Mount Annan; these should be maintained for possible use in ex-situ conservation.
- Seed has been collected and placed into long term low temperature storage as an insurance against the possible unexpected loss of the wild population due to a stochastic event. This stored seed may need to be accasionally replaced if testing showed that the seed viability had dropped significantly after a lengthy period of storage.
- 80 individaul wire mesh guards have been placed around a total of 103 plants to protect them from wallaby browsing and to allow them to contribute an onging supply of fresh seed to the site. This will ensure a substantial number of individuals survive and will hopefully provide the capacity for ongoing recruitment of new individuals. The mesh guards currently installed will need to be maintained and new guards may need to be placed around a selection of new seedlings to replace other guarded plants that will eventually die of old age.
- Monitor population for impacts of stochastic events, the effectiveness of the individual guards and for any improved recruitment in response to the protection of a large number of individuals within the population.
- Longer term management of the site should include the fencing of the entire outcrop on which the species occurs to exclude wallaby browsing entirely from within the population. This would assist newly established seedlings to survive without the need to guard individual plants. Fencing the entire outcrop will be expensive in the rocky terrain.
- The current landowners are highly supportive of the conservation program to protect and maitain the species. Ongoing liaison with the landholders needs to be maintained to keep them informed on progress and any changes to the program that may appear neccessary. If there were to be a change in ownership at some point in the future, the new owner/s would need to be contacted and briefed on the staus of the species and the conservation works that have been undertaken to date.
Information sources
- NSW National Parks and Wildlife Service (2002) Zieria buxijugum (a shrub) Recovery Plan. NSW NPWS, Hurstville NSW.
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IBRA Bioregion
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IBRA Subregion
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Known or predicted
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Geographic restrictions region
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| South East Corner | South East Coastal Ranges |
Known
| West of the Princes Highway and within 20 km of Pambula |