Invasive weed 1: Blackberry

Name: Blackberry
Scientific name: Rubus anglocandicans, R. fruticosus agg.
Other names: European Blackberry
Level: Category 3 restricted invasive plant

The Blackberry is a woody, shrub that grows in thickets and is characterized by their reddish-purple stems with numerous hooked thorns. Leaves of the Blackberry shrub are dark green on the upper side, whitish underside and has hooked thorns on the leave stalks. Flowers are white or pink, 2-3cm diameter and form clusters at the end of branches. Blackberry fruit changes from green to red to black with each segment containing one seed (business.qld.gov, 2020).

Figure 1: Blackberry fruit

Figure 2: Blackberry flowers

Figure 3: Blackberry stalk with thorns 

Blackberry seeds are spread mostly by animals such as foxes and birds as they feed on the fruit and take the seeds to new areas. Seeds can also be dispersed by water ways, creeks, gullies and rivers (Aghighi et al, 2014). Stems of the Blackberry plant are able to send out roots, forming daughter plants and expanding the infestation. In Queensland, blackberry plants occur in Stanthorpe, Warwick, Killarney and Toowoomba areas and prefers temperate habitats(Gomez et al, 2008).

In effort to control the spread on the Blackberry plant, small plants are pulled out of the ground and dispose by burning. Slashing/cultivation/burning Blackberry plants when appropriate and replace with native vegetation to help slow the spread. A rust fungus can slow the rate of spread but does not kill the weed and should not be relied on as an adequate control (business.qld.gov, 2020).

References

Aghighi, S., Fontanini, L., Yeoh, P.B., Hardy, G E St J, Burgess, T.I. & Scott, J.K. 2014, "A Conceptual Model to Describe the Decline of European Blackberry (Rubus anglocandicans), A Weed of National Significance in Australia", Plant disease, vol. 98, no. 5, pp. 580-589.

Gomez, D.R., Evans, K.J., Baker, J., Harvey, P.R. & Scott, E.S. 2008, "Dynamics of Introduced Populations of Phragmidium violaceum and Implications for Biological Control of European Blackberry in Australia", Applied and Environmental Microbiology, vol. 74, no. 17, pp. 5504-5510.

https://www.business.qld.gov.au/industries/farms-fishing-forestry/agriculture/land-management/health-pests-weeds-diseases/weeds-diseases/invasive-plants/restricted/blackberry retrieved 26/04/2020