2019-20 Weeds Report now available

The State Herbarium of South Australia documents all known plant taxa (species, sub-species, varieties and forms) native and naturalised (weedy) in South Australia. These taxa are listed in the Census of South Australian Plants, Algae and Fungi. All newly discovered State and regional records are added to the Census throughout the year. The records are based on preserved plant specimens, verified by a botanists, and housed in the vaults of the State Herbarium.

Hedera hibernica at Leg of Mutton Lake, Mount Gambier. Photo: A. Laslett.

For all new records of non-native plants, an annual report is produced by the Weeds Botanist Chris Brodie and colleagues from the State Herbarium. The report includes the list of new weeds recorded for South Australia with locations, descriptions, and photographs. Also documented are updates to other taxa that have had a change in distribution, weed status or name. Other activities carried out by Weeds Botanist are also summarised, such as field trips or presentations to community groups.

The latest report is now available online:

Brodie, C.J., Lang, P.J., Vonow, H.P. & Waycott, M. (2020). Regional Landscape Surveillance for New Weed Threats Project, 2019-2020: Annual report on new plant naturalisations in South Australia. (16mb PDF).

Also available for download are last year’s 2018-19 report (4.2mb PDF), as well as the reports for 2017-18 (4.5mb PDF), 2016-17 (3.8mb PDF) and a compilation of all reports from 2010 to 2016 (3.7mb PDF).

These reports highlights to land managers, which non-native plant species have recently been found in South Australia and where. New records are listed as either “naturalised/established” (*) or “questionably naturalised/established” (?e).

Isopogon latifolius, naturalised in South Australia. Photo: C.J. Brodie.

Naturalised plant taxa are those that have originally been introduced by humans to an area, deliberately or accidentally. They have self-propagated without aid where they are not wanted, possibly spreading by natural means to new areas. Examples listed in the recent report is Hedera hibernica (Irish ivy Link here) from Europe and the closely related Hedera algeriensis (Algerian ivy), originally from Northern Africa. Both of are examples of garden plants that have become weedy (see also a 1985 article by P.M. Kloot; 733kb PDF). Australian species can also become weeds, with Isopogon latifolius (Drumsticks) and Eucalyptus salubris (Gimlet) both from WA.

Questionably Naturalised plant taxa (i.e. possible new weeds) are introduced non-native plants that may be self-propagating without aid, but are not well established or lack data to classify them as naturalised. An example of this are Gasteria obliqua (Lawyer’s tongue) and the hybrid Populus ×canescens (Grey poplar).

At the end of June 2020, there were 5134 vascular plant taxa recognised in South Australia, of which 1611 are weeds, i.e. 31%. This year, 17 new weeds have been added to the Census; and over the last ten years, Chris Brodie’s weed surveys have discovered 236 new naturalised plants.

Any unknown or possible new state or regional weed records should be reported to Chris Brodie (0437 825 685, chris.brodie@sa.gov.au). If you have permission from the landowner, you could press a plant, record collection data, and submit a preserved plant specimen for identification.

The pressed plant or part thereof should consist of stems with leaves attached and preferably flowers and/or fruit. Collection data includes, plant location, habitat, frequency, height and width, colour and smell, and what the plant looks like when alive and growing. Images can also help in identifying plants. Also include the date, your name and contact details.

Please use the pro-forma collection sheet (available as single page: 200kb PDF, or for double-sided printing: 220kb PDF) in pencil and submit it together with the pressed plant specimen.

Compiled by State Herbarium
weeds botanist Chris Brodie.