Planting Approach
Active restoration planting will be of limited extent and will be undertaken to achieve the following outcomes:

• Expand the area of black beech forest at Remnant “B” (Zone 1)
• Establish an additional area of black beech forest somewhere within Zone 2.
• Fill key gaps between the regenerating kanuka areas across the inland faces (Zone 2)
• Form a riparian buffer along the coastal section of Kate Valley Stream (Zone 6)
• Establish indigenous vegetation within and around the margin of the Kate Valley wetland (Zone 3)
• Establish podocarps into the existing kanuka stands (especially Zones 2 and 4).
• Provide year-round food resources for korimako and kereru (throughout).

A variety of planted species will be used to buffer the restored system against the vagaries of reproduction failure of individual species and to provide a diverse habitat for native birds through all seasons. The assumption is that these birds, and some introduced birds, will, in turn, play a key role in dispersing planted species more widely in Tiromoana Bush.

The general approach to planting encompasses five steps:

1. Plant ecologically appropriate species adapted to dry conditions. Some more sensitive species can be planted in sites that naturally accumulate water or on shady aspects where evaporation is lowest.
2. Plant in late winter/early spring to avoid winter frosts but provide the longest possible time for root systems to develop before summer droughts occur.
3. Before planting, use herbicide to kill grass to lessen the competition for water while the tree or shrub establishes. Fertiliser will be applied during planting to ensure good initial root growth.
4. If necessary, plants can be aided during establishment in very dry seasons with the cautious use of irrigation from the existing farm water system.
5. Some release weeding/spraying is usually necessary to clear back encroaching grass after planting. Once their root systems develop (over the first three growing seasons) they should survive grass competition.

Collection and propagation of planting material
The remnants of indigenous forest and areas of regenerating forest in Tiromoana Bush, together with other forest remnants in the general area and experience with other restoration projects in similar environments (e.g., on Banks Peninsula) will be used to select species for restoration. Species choice will focus on those that are adapted to local conditions and that will grow rapidly and provide suitable conditions for subsequent indigenous regeneration. In addition species choice will be influenced by a need to ensure that sufficient food resources are available to sustain a korimako population in the area and to provide conditions suitable for the establishment of a local kereru population.

Overall species choice represents a balance between those species that will grow best under the prevailing environmental conditions, are likely to contribute most to meeting the restoration goals, and be most attractive to seed dispersing birds. At a local site level, species choice needs to consider the main limitations to plant growth (moisture, frost, exposure, infertility and competition) associated with particular microsites. This can be guided by the success of restoration plantings as they are established as well as the general ecology of species in remnant coastal forest in the Motunau Ecological District. However, species choice needs to be regularly reviewed based on the performance of plantings, especially during dry years, and the availability of propagated material.

An additional consideration in determining species for planting is the need to ensure that year-round food supplies are available for species such as korimako and kereru. There is a considerable amount of information available on the diet of these birds and this information will be used to ensure that sufficient food resources are available year-round to sustain them.

Sources of plant stock for propagation to be grown in Tiromoana Bush are seeds and cuttings from wild plants growing in the same area, or within the southern part of the Motunau Ecological District. Where seed supplies are inadequate or where seed germination is poor, cuttings will be used for propagation so long as sufficient material is available from the collection site. This project will require a substantial number of plants to be collected and propagated. This work will be undertaken by an experienced plant propagation contractor. Decisions on appropriate methods for plant collection and propagation will be based on discussions between Transwaste Canterbury Ltd. staff and the contracted plant propagator.

Site preparation and planting
The majority of planting sites are covered with pasture grasses. The main species are perennial grasses with a mat of underground rhizomes (browntop, red fescue, field poa, cocksfoot). These grasses compete vigorously for the limited available water resources and they can smother young plantings, while their presence makes planting physically difficult. Primary site preparation involves removing these grasses permanently from the planting sites.

Planting methods, including fertiliser use, will be based on discussions between Transwaste Canterbury Ltd. staff and the contracted plant propagator and/or planter. In general, plantings will be at 1.5 m spacing, with fertiliser added prior to planting. The underlying approach to restoration is through appropriate site preparation and use of good quality plants, post planting management should be kept to a minimum. The intention is that once established, the restored areas should require minimal direct human intervention unless something unexpected occurs (e.g., an extreme weather event). However, some post-planting management will be required to deal with drought years, weed invasion, nutrient deficiencies and major planting failures.

The timing of restoration activities during the year is largely dictated by climatic conditions and the plant growth patterns. The annual work cycle is focussed on late-winter/spring planting with the aim of gaining full benefit from the period when soil moisture is likely to be at a peak. However, plants must also be suitably hardened off prior to planting in order to withstand conditions at the time of planting. Sites protected from severe frost may be planted in late July, but in more frost-sensitive sites planting should be delayed until August or September. The following is a summary of the main restoration activities and their timing.

Autumn - site preparation, planning for next years requirements.
Winter – hardening off, transport of plants to site, planting (late-winter).
Spring – finish planting, post planting maintenance.
Summer – seed collection, general maintenance, provision of water during dry periods.

Inter-planting will be used to enrich areas of gorse and regenerating kanuka. In gorse, enrichment plantings will involve cutting lines or strips through the gorse and establishing indigenous plants along these. The intention here is to speed up the replacement of gorse by indigenous vegetation, but continuing to utilise the gorse for shelter. Strategic plantings of later canopy dominants, especially totara and matai, will also be made into areas of regenerating kanuka forest. In these instances, small clearings will be made in the kanuka canopy to enhance light levels and thus aid growth of the planted species.

Remnant “A” provides a valuable resource for restoration. Where possible plants will be removed from remnant “A” and transplanted into appropriate sites in the restoration area, while seed and cuttings will be extensively collected from here over the period before it is removed. Soil duff from Remnant “A” will be used to inoculate nursery grown plants, especially of kanuka and black beech. Close to the time of removal, as much of the forest organic material and coarse woody debris as possible will be salvaged from Remnant “A” and spread through accessible parts of the restoration area and regenerating forest. This should facilitate regeneration in these areas and also help transfer some of the fauna associated with Remnant “A”. Advice will be sought at the time this occurs on the best approaches to do this.

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