Pink ragwort returns

IT’S BACK: Kaiti Hill/Titirangi is one again covered in pink flowers from holly-leaved senecio, also known as pink ragwort. Gisborne District Council said it was controlling the weed on Titirangi, which was acting as a nurse crop to natives planted in 2015. Picture by Liam Clayton

KAITIHill/Titirangi is once again glowing pink with the spring flowers of the invasive weed holly-leaved senecio, and Gisborne District Council is again defending its management plan.

The weed, also known as pink or purple ragwort, drew much publicity last year after it sprouted on the north-east face of Titirangi, where pine was harvested in 2015 and replanted with native trees.

Senecio is categorised as a “progressive containment plant” in the regional pest management plan.

People are required to notify council staff within 21 days of finding it on their property.

They then have 21 days to destroy or control it, and maintain a 50-metre boundary clearance to neighbouring properties to prevent the seed spreading.

After the weed appeared last spring on Titirangi, rather than pull it out and risk spreading the 150,000-200,000 seeds each plant could produce, the council opted to control it and leave it to act as a nurse crop to the new native plants.

The council estimated it would cost about $70,000 for a one-off hand pull but due to the “seed bank” the senecio would continue to grow and require continuous removal.

Clearing boundaries

The council had been clearing the boundaries on council-controlled areas of Titirangi of senecio this winter before the weed seeded.

Council liveable communities director Andrew White said he was happy with how senecio had been dealt with on Titirangi.

“Although there is a lot of it on Titirangi, especially in the pine harvest site, we are containing it well within our boundaries and monitoring it by keeping a careful eye on neighbouring boundaries.

“Natives planted in the harvest site in 2015 are doing well and the advice we have received from the Department of Conservation and our bio-security team is that once the natives outgrow the senecio, which could be in the next season or two, they will smother the light from the weeds, killing them.”

Outbreaks of senecio on other sites, including the hills around Makorori, were unlikely to have come from Titirangi.

“Holly-leaved senecio has been present at Makorori for a number of years and has nothing to do with a spread from Titirangi.”

Seeds were generally spread by wind but other sources of infestation could occur from infected machinery, contaminated soil and humans.

“Localised infestations are clearly seen on poorly managed pasture land, harvested pine forest lots, reserve land, wasteland areas and roadside margins,” Mr White said.

The council’s advice was to pull it out during winter before it seeded, or pull it out when first discovered and look out for it the following winter.

Holly-leaved senecio is a South African perennial with an upright, rigid woody stem and can grow up to two metres tall. The leaves are tooth-edged and stiff, and produce bright pink or purple flowers in October.

The plant was introduced to the Gisborne district as a garden ornamental but spread and is now established locally.

KAITIHill/Titirangi is once again glowing pink with the spring flowers of the invasive weed holly-leaved senecio, and Gisborne District Council is again defending its management plan.

The weed, also known as pink or purple ragwort, drew much publicity last year after it sprouted on the north-east face of Titirangi, where pine was harvested in 2015 and replanted with native trees.

Senecio is categorised as a “progressive containment plant” in the regional pest management plan.

People are required to notify council staff within 21 days of finding it on their property.

They then have 21 days to destroy or control it, and maintain a 50-metre boundary clearance to neighbouring properties to prevent the seed spreading.

After the weed appeared last spring on Titirangi, rather than pull it out and risk spreading the 150,000-200,000 seeds each plant could produce, the council opted to control it and leave it to act as a nurse crop to the new native plants.

The council estimated it would cost about $70,000 for a one-off hand pull but due to the “seed bank” the senecio would continue to grow and require continuous removal.

Clearing boundaries

The council had been clearing the boundaries on council-controlled areas of Titirangi of senecio this winter before the weed seeded.

Council liveable communities director Andrew White said he was happy with how senecio had been dealt with on Titirangi.

“Although there is a lot of it on Titirangi, especially in the pine harvest site, we are containing it well within our boundaries and monitoring it by keeping a careful eye on neighbouring boundaries.

“Natives planted in the harvest site in 2015 are doing well and the advice we have received from the Department of Conservation and our bio-security team is that once the natives outgrow the senecio, which could be in the next season or two, they will smother the light from the weeds, killing them.”

Outbreaks of senecio on other sites, including the hills around Makorori, were unlikely to have come from Titirangi.

“Holly-leaved senecio has been present at Makorori for a number of years and has nothing to do with a spread from Titirangi.”

Seeds were generally spread by wind but other sources of infestation could occur from infected machinery, contaminated soil and humans.

“Localised infestations are clearly seen on poorly managed pasture land, harvested pine forest lots, reserve land, wasteland areas and roadside margins,” Mr White said.

The council’s advice was to pull it out during winter before it seeded, or pull it out when first discovered and look out for it the following winter.

Holly-leaved senecio is a South African perennial with an upright, rigid woody stem and can grow up to two metres tall. The leaves are tooth-edged and stiff, and produce bright pink or purple flowers in October.

The plant was introduced to the Gisborne district as a garden ornamental but spread and is now established locally.

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Realist - 2 months ago
Containment?
Rolling on the floor with laughter!
The side of Kaiti Hill is now obviously a massive reservoir crop of pink ragwort ragwort seeds, being oh-so generously wind-spread around.

Anne Salmond - 2 months ago
A large area where pine has recently been harvested in Cave Road is now also covered with pink ragwort, which is spreading up the Waimata Valley. The council's 'containment' strategy on Titirangi has been very unhelpful, allowing this invasive weed to spread far and wide, passing on costs to many other landowners and threatening current ecological restoration projects along the Waimata river.