×

Warning

JUser: :_load: Unable to load user with ID: 504

Notice

Thank you for visiting our website.

Please note that the site is not fully functional at the moment as we are in the process of re-developing. We hope that you will find the available resources helpful in the meantime.

German wasp | Vespula germanica

German wasp

Vespula germanica

Coral bush | Ardisia crenata

Coral bush

Ardisia crenata

Purple loosestrife | Lythrum salicaria

Purple loosestrife

Lythrum salicaria

Pom pom weed | Campuloclinium macrocephalum

Pom pom weed

Campuloclinium macrocephalum

Canarybird bush | Crotalaria agatiflora

Canarybird bush

Crotalaria agatiflora

Peanut butter cassia | Senna didymobotrya

Peanut butter cassia

Senna didymobotrya

Rubber vine | Cryptostegia grandiflora

Rubber vine

Cryptostegia grandiflora

1 2 3 4 5 6 7

Environmental Programmes

In order to tackle our country’s socio-economic challenges, the government adopted the Outcomes based approach to improve government performance and providing focus on service delivery. find out more

Alien grasses: The current local perspective and forming a “National Working Group on Alien Grasses”

Alien grasses: The current local perspective and forming a “National Working Group on Alien Grasses”
Vernon Visser1 and John Wilson1,2
1Centre of Excellence for Invasion Biology, Private Bag X1, University of Stellenbosch, Matieland 7602,
2Invasive Species Programme, South African National Biodiversity Institute, Private Bag X7, Claremont, 7735..
Email:

The grasses form the fourth largest plant family with over 11,000 species with some of the most important crop and pasture species, so it is not surprising that many grass species have been extensively moved around the world. Some of the best examples of invasive species causing radical ecosystem transformations are also the result of introduced grasses—e.g. radically altered fire regimes—with grasses of African origin having often the largest impacts. Comparatively, Africa appears to have suffered far smaller impacts from invasive grasses, with some notable exceptions, e.g. giant reed (Arundo donax), Pampas grass (Cortaderia selloana) Kikuyu grass (Pennisetum clandestinum) and a number of annual grasses of Eurasian origin. Grasses have also received far less attention than woody plants in South Africa, not least because of the difficulty of distinguishing between many grass species. This suggests that there are probably far more exotic grass species in South Africa, at various stages of the invasion process, than we are currently aware of. In addition, increased interest in growing exotic grass species for biofuel (e.g. Arundo donax, Miscanthus spp., Sorghum halepense) or for carbon offsetting (e.g. various bamboo species; e.g. www.trees.co.za/bamboo-for-africa/) is resulting in the introduction of new species and genetic strains of species, and extensive plantings of these species, making the chances of these species becoming invasive much more likely.

Revisiting the paper by Milton in 2004, I will discuss the current state of knowledge of alien grasses in South Africa and around the globe, and provide a brief overview of current and potential impacts of alien grasses both locally and globally. I will then provide an overview of a proposed alien grass working group for South Africa, whose aims will possibly be twofold:

1)   producing an inventory of all known alien grass species in South Africa;

2)   and conducting a national risk assessment of potential alien grass invaders.

Anyone interested in participating in a working group to achieve these aims is encouraged to attend. This session is intended as an open platform for discussion on the issue of alien grasses in South Africa and the input from interested parties would be most welcome. We also intend to set dates for a possible workshop to be held in Stellenbosch, to further the abovementioned aims.

REFERENCES

CLAYTON, W.D., HARMAN, K.T. & WILLIAMSON, H. 2006 onwards. GrassBase - The Online World

Grass Flora. Available at http://www.kew.org/data/grasses-db.html.

D'ANTONIO, C. & VITOUSEK, P.M. 1992. Biological invasions by exotic grasses, the grass/fire cycle, and global change. Annual Review of Ecology and Systematics 23: 63-87.

VAN WILGEN, B.W., REYERS, B., LE MAITRE, D.C., RICHARDSON, D.M. & SCHONEGEVEL, L. 2008. A biome-scale assessment of the impact of invasive alien plants on ecosystem services in South Africa. Journal of Environmental Management 89: 336-349.

MUSIL, C.F., MILTON, S.J. & DAVIS, G.W. 2005. The threat of alien invasive grasses to lowland Cape floral diversity: an empirical appraisal of the effectiveness of practical control strategies. South African Journal of Science 101: 337-344.

MILTON, S.J. 2004. Grasses as invasive alien plants in South Africa. South African Journal of Science

100: 69-75.

HENDERSON, L. 2007. Invasive, naturalized and casual alien plants in southern Africa: a summary based on the Southern African Plant Invaders Atlas (SAPIA). Bothalia 37: 215-248.

BLANCHARD, R., RICHARDSON, D.M., O’FARRELL, P.J. & VON MALTITZ, G.P. 2011. Biofuels and biodiversity in South Africa. South African Journal of Science 107: 19-26.

Read 3459 times

General News Updates

2019 National Symposium on Biological Invasio…

26-02-2019

This is your invitation to South Africa's 2019 National Symposium on Biological Invasions. The convention is hosted by the Centre for Invasion Biology (CIB), University of Stellenbosch, and the Biolo... Read more

2019 Invasive Species Training

22-01-2019

During the past five years (2014-2018), ISSA invasive species trainers have trained 4 000 in the identification of invasive species and laws pertaining to invasive species across South Africa.  ... Read more

Alien Grass Working Group

04-09-2018

Who are we? The South African National Alien Grass Working Group was jointly initiated by the South African Biodiversity Institute (SANBI) and the Centre for Excellence in Invasion Biology (C·I·B) in... Read more

Permits for planting indigenous Cynodon?

01-03-2018

On 16 February, 2018, South Africa's Department of Environmental Affairs issued amendments to the regulations and lists relating to the National List of Invasive Species.  Updates to the draft&n... Read more

Invasive species training 2018 dates released

28-02-2018

Interested in invasive species?  How much do you know about NEMBA invasive species compliance for landowners and organs of state? The South African Green Industries Council (SAGIC) have released... Read more

Communications post for Africa advertised

25-01-2018

The Nature Conservancy has advertised a brand new post:  Communications Manager, Africa Region. Knowledge of invasive species and water would be an asset in this post. See details below:    Job Titl... Read more