Botanical Society Visit to Manawa Karioi

7 July 2018: Manawa Karioi Reserve

Eleven people braved the cold showery weather and were rewarded with a largely clear day for their exploration. Manawa Karioi is easily accessible from Danube St or Rhine St, Island Bay. Although privately owned by the Tapu Te Ranga Marae Trust, it is publicly accessible. As one of Wellington’s earliest restoration projects, and one which has been undertaken with ecological integrity from the outset, it is worth botanists’ attention and has recently been included in a comprehensive Waikato University study of urban forest restoration sites across NZ.

We traversed the main tracks in the northern part of the reserve and spent most of our time in two gullies where a range of restoration plantings have been concentrated. We had the benefit of an early (1992) species list compiled by Maggie Wassilieff, and a comprehensive up to-date list compiled by Pete Russell. The latter included a vast list of plant pests and other adventive NZ native and introduced species, indicating the size of the task any reserve manager hoping to undertake serious ecological restoration in a city suburb must undertake. We inspected and discussed the range of species planted.

In recent years Manawa Karioi has enriched the early planted successional species such as ngaio, Veronica parviflora, Coprosma spp, puka, kawakawa, māpou etc., with small numbers of later successional species including tawa, kohekohe, northern rātā, porokaiwhiri, Sophora spp, black maire, and the podocarps rimu, mataī, miro, kahikatea and tōtara, plus a few vines including kiekie and puawhānga.

All species planted since the start have been locally ecosourced. We were pleased to see the range of planted species that are now freely regenerating, including tōtara, ngaio (very prolific and probably now the most significant forest canopy dominant), kōwhai, and many smaller broadleaved trees. We also saw small apparently regenerating puawhānga (now flowering, see photo), and a few planted swamp maire which are doing well. Thanks to Eleanor who collated the species observations which included several additions to the list, including six fern species. We also observed for the first time Coprosma areolata which may well have selfintroduced from Tawatawa Reserve across the ridge. Non-local natives such as karaka, karo, lacebark and five-finger hybrids are also thriving, and we discussed weed control priorities, which Manawa Karioi are now reassessing.

Our pick of the most urgent control priorities included climbing asparagus, wild ginger, Darwin’s barberry, flowering cherry, privet and karo. With the exception of karo, these are all of relatively limited distribution in the reserve. We felt that generally the reserve was in good condition with fewer weeds impeding native succession than in comparable Wellington reserves.

Participants: Paul Blaschke (leader/scribe), Eleanor Burton, Gavin Dench, Michelle Dickson, Richard Grasse, Kate Jordan, Rodney Lewington, Russell Poole (Palmerston North), Peter Russell (Manawa Karioi group), Sunita Singh (co-leader), Xavier Warne.