Boxthorn
Botanical Name
Lycium ferocissimum
Family
Solanaceae (nightshade)
Also known as
African boxthorn
Where is it originally from?
South Africa
What does it look like?
Densely branched, erect, evergreen shrub (<6 m tall) with tough, woody stems alternately branched at square angles, forming a box-like pattern, and with rigid spines (13 mm). Hairless, fleshy, bright green leaves (40 x 12 mm) are narrow, oblong and clustered along the stems. White to pale mauve flowers (10-13 mm) produced from July to March are followed by tear shaped orange red berries (5-12 mm) in autumn.
Are there any similar species?
Hawthorn and barberry are similar. Lycium barbarum (L. chinense) is similar but is deciduous.
Why is it weedy?
Forms dense, tall, long-lived stands, excluding most other vegetation. Tolerates a wide variety of soil types (sand to rocky cliffs), drought, salt, wind, and hot to cold temperatures. Poisonous (usually not grazed).
How does it spread?
Birds and possibly possums. Common seed sources are farm hedges, roadsides, waste places.
What damage does it do?
Overtops native plants and can become only woody plant species on site. Petrels and other seabirds can become entangled and die. Berries may poison birds.
Which habitats is it likely to invade?
Sand dunes, shrublands, cliffs, islands and other coastal areas, gravel, and roadsides.
What can I do to get rid of it?
1. Physical removal - dig out small plants or excavate larger areas. Dispose or burn all plant material.
2. Cut and paste - Cut the stem/trunk as close to the ground as possible and cover the entire stump with herbicide as soon as possible after cutting. Apply glyphosate gel (120g/L strength).
3. Basal spray - stems up to 20cm diametre with X-Tree Basal. Ensure the base is thoroughly covered at ground level.
4. Foliar spray (all year round) - knapsack for plants <1m tall or gun and hose for larger infestations.
Apply glyphosate (360 g/L active ingredient) herbicide (20ml/L) plus organosilicone penetrant (2ml/L) to cover entire plant Note: Non selective. Avoid overspray onto desirable plants.
OR apply triclopyr herbicide (600g/L active ingredient) at 6ml/L plus organosilicone penetrant (1ml/L) to thoroughly wet all parts of plant.
OR apply picloram/triclopyr herbicide (picloram 100g/l and triclopyr 300g/l active ingredient) at 6ml/L plus organosilicone penetrant (1ml/L) to thoroughly wet all parts of plant.
Note: tricolopyr and picloram herbicides are 'grass friendly' but overspray will kill other (desirable) broadleaf plants. Picloram has residual activity in the soil which may leach through soil and kill other plants. Do not use under and around other (desirable) broadleaf plants.
CAUTION: When using any herbicide or pesticide, PLEASE READ THE LABEL THOROUGHLY to ensure that all instructions and directions for the purchase, use and storage of the product, are followed and adhered to.
What can I do to stop it coming back?
Untreated stumps regrow after slashing. Not controlled by fire. Prefers open sites, so revegetate any bare ground left after clearance.
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