Boneseed

Chrysanthemoides monilifera

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DESCRIPTION

Boneseed is another pesky import, originally as a garden plant, but now a growing pest especially in coastal sites.  It is originally from the Cape Province of South Africa.

It’s a bushy shrub with many branches and reaches between 2 and 3 metres in height.  Once established on a site, Boneseed will form very dense thickets that displace native vegetation, and also make human access very difficult.

Flowers are bright yellow, daisy-like and the flowers heavily cover the bush in the September to February period.  

The fruit is spherical, about 8mm in diameter, and is initially green.  It becomes black and more rounded as it develops.  The outer fruit covering flakes away as it ripens, exposing a single whitish seed that is very hard (hence the name boneseed).  The seed is spread by birds, water, and soil movement.  A mature bush produces many thousands of viable seeds annually, and the seeds can remain dormant for 10 years before germinating.  This means that complete eradication will be a multi-year project.

Leaves are green, smooth and leathery, and oval in shape.  They’re about 7cm long by 3.5cm wide, with bluntish pointed tips.

Stems are ribbed and tough and become smooth with maturity.

Boneseed prefers coastal sites, roadsides, native scrubland, and waste areas.  It does not tolerate well sites that are shaded or soils that are wet.

Distribution is throughout coastal North Island and the north and east margins of the South Island.

Boneseed is subject to Pets Plant Management Strategies in several regions of NZ, and its sale or propagation is prohibited throughout the country.

HERBICIDE CONTROL OF BONESEED

Herbicide Sprays to Kill Boneseed

This is most suitable for smaller plants where reasonable access for overall spraying is available.

• G-360 GLYPHOSATE at 100ml/10L water, or G-540 GLYPHOSATE at 70ml/10L water or, Granny Herbicide at 45g/10L water, in all cases with SuperWetter at 20ml/10L water.
• MSF600 at 5g/10L water plus 20ml SuperWetter.
• GrassMate at 60ml/10L water plus 20ml SuperWetter.

Stump Swabbing Herbicides to Kill Boneseed

Cut the stems as close as possible to the ground and remove all cut material from the stump.  Swab the freshly cut surface and sides of each stump using a hand sprayer or a paintbrush.  Herbicide choices are:

• G-360 GLYPHOSATE at 1 part to 4 parts water, or Granny Herbicide at 1 part to 6 parts water or, G-540 GLYPHOSATE at 1 part to 5 parts water
• GrassMate at 1 part to 20 parts water (i.e. 50ml/L)
• MSF600 at 5g/L of water plus SuperWetter at 10ml/L.

Cut'n'Paste Herbicide Gels to Kill Boneseed

Cut'n'Paste Bamboo Buster

1. Cut the weed down to about 2cm above a node and dispose of cuttings appropriately.
2. Take your bottle of Cut'n'Paste Bamboo Buster, hold it upside down and gently squeeze a layer of Bamboo Buster onto the whole surface of the cut stem from the edge to the centre.
3. Leave it to die off.
4. For the best effects paste the Bamboo Buster onto the Bamboo immediately after cutting.

Once boneseed is initially treated and controlled successfully on a site, some follow up treatments will be necessary. Subsequently, the planting of dense and shady natives on the site will minimise future boneseed germination from the soil seed bank.