Pimelea orthia – a threatened plant

Shakespear Open Sanctuary is a sanctuary not only for birds and reptiles but also for rare and threatened plants. Pimelea orthia is one such plant. It is possible that the Park’s pest free status is allowing its numbers to expand as well as the suitable habitat being present.

The New Zealand Plant Conservation Network categorises the conservation  status of this plant as Threatened – Nationally Critical. It is endemic and found in scattered localities throughout the North Island. Its habitat includes coastal to lowland, in open scrubland to grassland overlying leached to infertile soil, or on dunes and open outcrops.

It was first recognized to exist on the NZ Defence Force land in 2011, growing on the roadside of one of the roads within this territory which is not open to the public. It was highly vulnerable to roadside spraying, but the plants have since been clearly marked and protected with battens and tape surrounding each plant.

Late in 2016 volunteers monitoring the robin population discovered another population when it was flowering strongly in another location on the Defence land and a further search in January 2017 located a third location. It is likely these populations have existed for some time, but as the plant is quite cryptic these had not been identified until the excellent flowering season revealed them.

This plant has not been found growing naturally in the main park, probably because the appropriate habitat is very limited there.

After the excellent flowering and fruiting season late in 2016 an attempt was made to grow new plants from seed. This succeeded very well and some plants have been planted alongside a few of the tracks in the park. Some of these plants have done well.