Spiny Rice-flower

Spiny Rice-flower. Image: Debbie Reynolds

 

Spiny Rice-flower
Pimelea spinescens spinescens 
Kingdom:   Plantae
Phylum:   Magnoliophyta
Class:   Magnoliopsida
Order:   Malvales
Family:   Thymelaeaceae
Status
Australia:  critically endangered
Victoria:  vulnerable  
FFG  listed

Grants  available to help this species

Pimelea spinescens subsp.spinescens, the Spiny Rice-flower is a perennial shrub growing from 5 - 30 cm in height. Leaves are green and oval-shaped about 2-10 mm long and grow from spine-tipped stems. It is estimated that only several thousand plants of this subspecies remain and that its close relative Pimelea spinescens subsp. pubiflora Wimmera Rice-flower is also Critically Endangered.

The Spiny Rice-flower is endemic to Victoria, with the South West being an important area for survival and recovery of this species. Approximately 90% of the population occurs in the Victorian Volcanic Plains Bioregion, the remaining populations occur in the western part of the Midlands and Riverina Bioregions. Within the Volcanic Plains Bioregion only about 9% of the population is protected in reserves, 5% Private, 36% PTC and 41% on roadsides managed by Surf Coast , Golden Plains and Corangamite Shires.1

spiny rice-flower map 2017

Distribution of Spiny Rice-flower in Victoria. Source: VBA 2017.

Habitat & ecology

The Spiny Rice-flower occurs on basalt soils and in areas that received low levels of disturbance often associated with Themeda triandra grasslands. The Spiny Rice-flower slow growing and may live as long as 100 years, flowering occurs from April to August, plants are dioecious (each plant is a either female or male but hermaphrodites have also been recorded).

Threats

Weed invasion; primarily from Phalaris and Tall Wheat Grass out compete Spiny Rice-flower for seed bed, germination and sunlight. Weed invasion can be compounded by inappropriate road works and lack of fire. Spiny Rice-flower can benefit from fairly frequent burning as a means of reducing competition for weeds.

Roadworks;  soil disturbance which extends beyond the roadside table drain and grading of road reserves for fire breaks can cause physical uprooting of plants or smothering of plants by spreading top soil. Inevitably soil disturbance results in weed invasion as new areas of loose bare soil favour germination from nearby sources of weeds.

Changed land use; conversion of roadside reserves into cropping areas completely removes native species such as Spiny Rice-flower.

Inadequate burning; a high biomass of grasses is a major threat to the Spiny Rice-flower at many sites. Planned burning is an essential tool in managing this species.

Conservation measures for Spiny Rice-flower

Conservation of the Spiny Rice-flower is dependent upon co-operation through a number of agencies and conservation organisations who either manage land or undertake conservation activities relating to this species.

A number of sites have been the subject of translocations associated with off-sets through rail, road and urban development which has involved both private and public intersests. Between 2009 and and 2012 at least 11 translocations were undertaken as a result of development activies.  Pimelea Translocation Assessment Report 06.03.14 (9MB) (to be added soon).

Demographic monitoring has been used to determine the presence of new germinants in populations of Spiny Rice-flower. This information is considered valuable as the species is slow growing and long lived. There is some concern remaining populations may largely consist of mature individuals with little active recruitment occurring.

Spiny Rice-flower. Image: Debbie Reynolds, TFN

 

Actions in Corangamite Catchment

Rokewood vicinity

Mt Mercer vicinity

Shelford - Mt Mercer Road

Surveys were conducted in 2010-11 by DELWP biodiversity officers and Debbie Reynolds from the Trust for Nature. A 10km stretch of roadside was burnt by the CFA in 2011-12 to reduce biomass which should assist Spiny Rice-flower recovery.

Shelford-Cressy Road

Foxhow-Rokewood Road

Lower Darlington roadside

Surveys during 2011-12 confirmed the presence of Spiny Rice-flower but found the population had substantially reduced from previous surveys (in 2007 over 700 plants down to 382 plants 2011-12). Urgent weed control of Phalaris along fire breaks is being undertaken.

Urches Road

Wingeel vicinity

Other sites in the Corangamite Catchment

Actions in Wimmera Catchment

Natimuk

Deep Lead Park Road

 
                   Spiny Rice-flower (female flowering plant),                                                          Images: Debbie Reynolds, Trust for Nature

 

Actions in Glenelg Hopkins Catchment

Blacks Creek Nature Conservation Reserve

Derrinallum area - Chatsworth Road

Spiny Rice-flower in flower within native grasslands.  Image: Jessie McMaster

References

Further reading

Help manage Pimelea spinescens  - grants available

The Pimelea Conservation Trust Fund invites applications each year. The 2018 applications open 11th June and close 31 August 2018. Successful applicants will be selected from applications by the Pimelea Conservation Trust Committee during November. All applicants will be informed of the outcome in December/January via email (the successful applicant/s will receive a formal letter).

All applications should directly relate the project to the objectives and corresponding actions of the published Pimelea spinescens Recovery Plan.

The applicants will need to detail which Recovery Plan objective/s and actions they are addressing, how they will be implemented, identify the risks of the project and measurable outcome/s/benefits for P. spinescens.

Generally, the total amount available each year is $12,000. However, this amount may vary at the Trust Committee’s discretion. A project’s time frame will be dependent on the project.

Contact  Debbie Reynolds, the Pimelea Conservation Officer, Trust for Nature
Phone: (03) 8631 5888 | Mobile: 0410 559 969 | Freecall: 1800 99 99 33 | Address: Level 5/379 Collins St, Melbourne VIC 3000

Pimelea Conservation Trust Fund 2018 application form

 

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