Blackberry
This Weed Risk Management Assessment uses a series of questions to arrive at scores for weed risk and feasibility of coordinated control for this weed, and displays the necessary management actions derived from these scores.
This information is then used to make decisions about the introduction, prioritisation and declaration of this weed in New South Wales.
| Weed (Scientific name) | Former aggregate Rubus fruticosus species only (exclusions in notes below). | ||
| Weed (Common name) | Blackberry | ||
| Region | All of NSW | ||
| Management area | Mainly conservation areas considered here although the weed is a problem for primary production. | ||
| Landuse | Conservation and Natural Environments | ||
| Assumptions | European species Rubus, Rosaceae. Standard weed management limited - some site treatment with herbicides & labour-intensive tools. Wide use of fire. Biocontrol. Density in land use - moderate. | ||
| Weed Risk | |||
|---|---|---|---|
| Invasiveness | Score Total | Answer | Source and comments |
| Q1. What is the ability of the weed to establish amongst existing plants? | 1.0 | Seedlings establish after moderate disturbance | Inferred from Amor et al. (1998), pg. 229, but could even be 'low'. |
| Q2. What is the weed's tolerance to average weed management practices in the land use? | 3.0 | 95% + weeds survive common management | NSW DPI (2009). |
| Q3. What is the reproductive ability of the weed in the land use? | 2.0 |
a. Amor et al. (1998), pg. 230 - for seedlings only. b. and c. Amor et al. (1998), pg. 233. | |
| (a) Time to seeding | 0.0 | >3 yrs/never | |
| (b) Annual seed production | 2.0 | High | |
| (c) Vegetative reproduction | 2.0 | Frequent | |
| Q4. How likely is long-distance dispersal (>100m) by natural means? | 0.0 |
a. and b. Amor et al. (1998), pg. 233. c. NSW DPI (2009), pg. 16. Wind not mentioned | |
| (a) Flying animals | 2.0 | Common | |
| (b) Other wild animals | 2.0 | Common | |
| (c) Water | 1.0 | Occasional | |
| (d) Wind | 0.0 | Unlikely | |
| Q5. How likely is long-distance dispersal (>100 m) by human means? | 2.0 |
NSW DPI (2009), pg. 16. Deliberate spread is probably quite limited as is sale due to a National ban. Domestic and farm animals not mentioned by either reference but may be occasional. | |
| (a) Deliberate spread by people | 1.0 | Occasional | |
| (b) Accidentally by people and vehicles | 1.0 | Occasional | |
| (c) Contaminated produce | 1.0 | Occasional | |
| (d) Domestic/farm animals | 1.0 | Occasional | |
| Total | 6.7 | ||
| Impacts | Score Total | ||
| Q1. Does the weed reduce the establishment of desired plants? | 3.0 | > 50% reduction | Unclear from Amor et al. (1998). Assumed >50% (from personal observations). Note NSW DPI pg. 11-12. |
| Q2. Does the weed reduce the yield or amount of desired vegetation? | 4.0 | > 50% reduction | Unclear from Amor et al. (1998). Assumed >50% (from personal observations). Note NSW DPI pg. 11-12. |
| Q3. Does the weed reduce the quality of products, diversity or services available from the land use? | 3.0 | High | Coutts-Smith and Downey (2006). |
| Q4. What is the weed's potential to restrict the physical movement of people, animals, vehicles, machinery and/or water? | 3.0 | High | NSW DPI pg. 11-12. |
| Q5. What is the weed's potential to negatively affect the health of animals and/or people? | 1.0 | Low | NSW DPI pg. 11-12 - but could be closer to medium. |
| Q6. Does the weed have major positive or negative effects on environmental health? | 0.0 |
NSW DPI (2008), pg. 11-12 a. Food and shelter to many native animals in the absence of any other. b. Fire hazard - also blocks fire trails and water access points. Once promoted for soil stability (Amor et al. 1998) but will increase erosion in heavily trafficked areas. | |
| (a) food/shelter | -1.0 | Major positive effect | |
| (b) fire regime | 1.0 | Major negative effect | |
| (c) altered nutrient levels | 0.0 | Minor or no effect | |
| (d) soil salinity | 0.0 | Minor or no effect | |
| (e) soil stability | 0.0 | Minor or no effect | |
| (f) soil water table | 0.0 | Minor or no effect | |
| Total | 7.4 | ||
| Potential distribution | Total | ||
| Q1. Within the geographic area being considered, what is the percentage area of land use that is suitable for the weed? | 8.0 | 60-80% of land use | Estimate (based on NSW DPI (2008), pg. 13. |
| Comparative weed risk score | 393 | ||
| Weed risk category | Very high | ||
| Feasibility of coordinated control | |||
| Control costs | Score Total | ||
| Q1. How detectable is the weed? | 1 | Personal observations - large thickets are generally > 2m high even though young plants are not. Below tree canopy. | |
| (a) Distinguishing features | 0 | always distinct | |
| (b) Period of year shoot growth visible | 0 | > 8 months | |
| (c) Height at maturity | 0 | > 2 m | |
| (d) Pre-reproductive height in relation to other vegetation | 2 | below canopy | |
| Q2. What is the general accessibility of known infestations at the optimum time of treatment? | 2 | low | Personal observations - there are accessible infestations but many in riparian areas are difficult to access. |
| Q3. How expensive is management of the weed in the first year of targeted control? | 4 | NSW DPI (2008), pg 44-57. | |
| (a) Chemical costs/ha | 2 | medium ($100-$249/ha) | |
| (b) Labour costs/ha | 4 | very high (>$500/ha) | |
| (c) Equipment costs | 1 | low | |
| Q4. What is the likely level of participation from landholders/volunteers within the land use at risk? | 2.0 | low | Personal observations. |
| Total | 7.5 | ||
| Persistence | Score Total | ||
| Q1. How effective are targeted management treatments applied to infestations of the weed? | 3 | low | NSW DPI (2009). |
| Q2. What is the minimum time period for reproduction of sexual or vegetative propagules? | 1 | 1-2 years | Amor et al. (1998), pg. 232-233. |
| Q3. What is the maximum longevity of sexual or vegetative propagules? | 0 | < 2 years | Amor et al. (1998), pg. 233. |
| Q4. How likely are new propagules to continue to arrive at control sites, or to start new infestations? | 2.0 | Amor et al. (1998), pg. 233. | |
| (a) Long-distance (>100m) dispersal by natural means | 1 | occasional | |
| (b) Long-distance (>100m) dispersal by human means | 2 | frequent | |
| Total | 5.5 | ||
| Current distribution | Total | ||
| Q1. What percentage area of the land use in the geographical area is currently infested by the weed? | 6.0 | 40-60% of land use | Estimate (based on NSW DPI (2008), pg. 13. |
| Q2. What is the number of infestations, and weed distribution within the geographic area being considered? | 2.0 | widespread | Personal observations. |
| Total | 6.7 | ||
| Comparative feasibility of coordinated control score | 273 | ||
| Feasibility of coordinated control category | Negligible | ||
| Management priority category | Manage weed | ||
| Calculation of overall uncertainty score | 0% | ||
| Positive impacts | Fruit and honey production - NSW DPI (2008) pg 12. Amor et al. (1998) - some species have been used as parents of commercial varieties. Wild fruit has been widely collected and made in jam in the past. | ||
| References/Other comments | |||
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Amor, R. L., Richardson, R. G., Pritchard, G. H. and Bruzzese, E. (1998). Rubus fruticosus L. agg.. In, Biology of Australian Weeds, Volume 2. F. D. Panetta, R. H. Groves and R. C. H. Sheppard. R. G. and F. J. Richardson, Melbourne. pp. 225-246. Coutts-Smith, A. J. and Downey, P. O. (2006). The impact of weeds on threatened biodiversity in NSW. Technical series no.11. CRC for Australian Weed Management Systems, Adelaide. 100 pp. NSW DPI (2009). Blackberry control manual: Management and control options for blackberry (Rubus species) in Australia. Department of Primary Industries, Victoria. 96 pp. Assessment by Dr Stephen Johnson, Weed ecologist, I&I NSW, 3 May 2010. This assessment only covers species in the former Rubus fruticosus aggregate - see NSW DPI (2009), pg. 20, Table 2.1. Species not covered by this assessment include native Rubus species (see NSW DPI (2009), pg. 21, Table 2.3) and the following exotic species Rubus laudatus (Bundy berry) - in the Sydney region. Rubus philadelphinicus (Lawton berry) - in Cooma region. Rubus loganobaccus (Logan berry) - in Canberra region. Rubus ellipticus (yellow Himalaya raspberry) - North east and Blue mountains regions of NSW. Rubus idaeus (raspberry) - in cooler areas. Rubus rugosus (keri berry) - Comboyne area of NSW. Rubus roribaccus (dew berry, young berry and boysen berry) - central coast and Sydney areas. Rubus alceifolius - not in NSW, only known from Cape Tribulation area of Qld (at this stage). Rubus odoratus - not in NSW, questionably naturalised in Australia. Rubus niveus - NSW North Coast - a separate risk assessment has been done for this species. Harbor for vermin. | |||
