Boneseed
Botanical Name
Chrysanthemoides monilifera
Family
Asteraceae (daisy)
Also known as
Synonym of: osteospermum moniliferum
Where is it originally from?
South Africa
What does it look like?
Bushy, semi-woody, much branched shrub or small tree (<2-3 m) with ribbed and woolly young stems that become smooth as they mature. Smooth, leathery, bright-green leaves (70 x 35 mm) have irregularly toothed edges and are arranged alternately on the stems. Bright yellow daisy-like flowers (25-30 mm diameter) are produced from September to February and are followed by hard oval green fruit (6-9 mm) which ripen to black and each contain a hard seed.
Are there any similar species?
Other weedy subspecies exist but none are known in New Zealand. Native Olearia species, Brachyglottis kirkii are similar but none have similar fruit.
Why is it weedy?
Quickly forms dense thickets. One boneseed bush can produce 50 000 seeds every year, and each seed can remain dormant for up to 10 years. Tolerates most coastal soil types, salt, fire, wind, poor soils, and drought.
How does it spread?
Seeds are spread by birds, possums, by natural spread down cliffs below parent plants, in flotsam, occasionally soil disturbance, and possibly livestock. Common in coastal gardens in some areas.
What damage does it do?
Rapidly replaces virtually all native species under 2 m and prevents the establishment of native plant seedlings. Colonises disturbed sites faster than native species, and creates heavy shade where high light levels should occur.
Which habitats is it likely to invade?
All coastal areas, cliffs, sand dunes, estuary margins, roadsides, and inshore islands.
What can I do to get rid of it?
1. Physical removal - Pull seedlings, dig out larger plants.
2. Cut and paste (all year round) - 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 either glyphosate gel (120g/L strength) or metsulfuron gel (10g/l strength) or picloram gel (43g/l strength) to the entire cut stem.
3. Foliar spray (Seedlings only) - 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.
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?
Germinates freely after fire or clearance leaving bare ground. Clear from adjacent coastal gardens to remove seed sources. Follow up 6-monthly. Encourage regeneration, densely replant cleared areas where necessary.
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