2. New on-line extension resources
New on-line ‘Guidelines for Growers’ are being created for potential growers, forest managers, consultants and regional land management advisers.
The resources comprise a series of modules including:
- Right tree, right place: why grow durable eucalypts?
- The NZDFI vision
- Regional strategies and resources
- Choosing the right growing regime
- Developing a planting plan
- Timber properties, utilisation and markets
- The economics of growing durable eucalypts
- The Xylogene brand.
The resources include new videos, downloadable handouts, and links to other sites and resources where relevant.
- WIDE Trust funding acknowledged
A recent application to the WIDE Trust for funds to assist with developing our extension resources was successful. We are grateful to the Trust for their support.
3. Recent SWP/NZDFI trial assessments
NZDFI’s tree breeding and forestry consultancy team has visited a number of trial sites over the past few months.
Three of these visits were to assess tree growth and form in breeding populations. Two assessments were made in Marlborough - at the E. globoidea at Avery’s and E. quadrangulata at Cuddon’s, both planted in 2011. Also the E. quadrangulata planted in 2016 at NZ Redwood Company’s Paparoa forest near Taumaranui was assessed.
Two additional visits were made to install new permanent sample plots (PSPs) in species demonstration trials planted in 2018 - at the NZ Redwood Company’s Paparoa forest and at Pāmu’s (Landcorp) Kapiro farm in Northland.
UC’s wood quality research team have also been working in two of our breeding populations to take thousands more cores to assess heartwood development and durability.
Thanks are due to all landowners for their continuing interest and in some cases assistance with trial assessment.
SOme results from two of these recent assesments are presented below:
- Avery’s 2011 E. globoidea tree breeding trial, Marlborough
The Avery trial located south of Seddon, Marlborough, was planted in 2011. This is on one of NZDFI’s driest sites with average annual rainfall of 638mm and periodic summer droughts typical of the area. The trial has excellent value to NZDFI in helping identify the top families for drought tolerance and productivity in low rainfall areas.
The trial includes one of three E. globoidea progeny trials (breeding populations) planted in September 2011 to select superior genotypes of this species for future deployment, the other two sites being Juken NZ Ltd’s Ngaumu forest (Masterton, Wairarapa) and the Atkinson trial (South Wairarapa). These three sites provide a broad representation of genetic diversity and express the adaptability of genotypes across different environments.
Interim results from Avery's trial
- Overall tree survival at Avery’s is 62% (38% mortality).
- Individual family survival ranged from 96.9% to 20.3%.
- There is significant variability in growth across the site, reflecting a combination of both genetic and site influences. Optimal growth was noted in the sheltered gullies and mid slopes.
- The diameter range is 40mm – 208mm with an average of 87.8mm.
- 21% of surviving trees were classified as un-measurable. These trees were typically located in the exposed or very dry blocks located across the site. These were stunted due to very dry conditions with some growing as a ‘mallee’ (multiple leaders growing from a lignotuber) form that is common in eucalypt species from very dry areas of Australia.
- Crown health is generally good throughout all surviving trees. There is minimal insect browse evident.
Assessments for straightness and form were completed in blocks that had 14 or more trees with DBH measurements (equating to approx. 40% survival in the block). Initial analysis has identified that top families already identified at both the Juken NZ’s Ngaumu trial and Atkinson’s trial were also surviving and performing well on this site.
Other work at the site
UC’s wood quality research team was also recently at Avery’s, taking cores to test for heartwood quantity. Further analysis of the family data from all three sites is planned once the assessments of wood properties from the cores have been undertaken. The entire Avery trial has now been marked up and thinned.
The NZDFI video team (Paul Millen, Harriet Palmer and Daniel Bozcniewicz) were the other recent visitors to Avery’s in December, filming two videos featuring E cladocalyx and E globoidea.
Our thanks go to Fraser Avery and family for their on-going support of NZDFI work.
- Pāmu /Landcorp 2018 demonstration trial, Northland
The Kapiro demonstration trial was planted in 2018 on an area of paddock and former woodlot. Here the average annual rainfall is 1600 mm and being in the ‘winterless north’, provides a stark contrast to some of our drier trial sites such as Avery’s.
The trial was assessed in late November with the trees just over two years of age. Data analysis has revealed that early tree growth of all species at this site has been the most productive recorded so far in any NZDFI trial of this age. The trial includes reps of a range of different seedlots of E. bosistoana, E. globoidea, E. macrorhyncha and E. quadrangulata to test their relative performance. All species have exceptional height and diameter growth. E. quadrangulata, which is known for its rapid early growth, was particularly impressive with E. globoidea not far behind. Some trees were over 8 metres in height!
Due to this rapid growth the trial will be low-medium pruned in February.
Thanks to Gordon Williams, Pāmu’s forestry manager and John Hallgarth, Kapiro farm manager who assisted in establishing this trial.
A summary of average height data by species. (click to enlarge)
A trial site map showing height data distribution.
Gordon Williams, Pamu’s forestry manager, inspects trees at Kapiro.
- E quadrangulata breeding trial update
Eucalyptus quadrangulata is the third principal species of NZDFI’s tree breeding programme. Recent work has advanced identification of superior families and development of clonal propagation techniques.
In the past six months two assessments of our E quadrangulata breeding trials have been completed, at Cuddons, Marlborough (planted in 2011), and NZ Redwood Company’s Paparoa trial in the central North Island (planted in 2016). Cores have also been collected by UC wood quality team from the older trees at Cuddons. Both trials were marked up and have been thinned.
Our thanks go to the Cuddons and Jack Burgess (NZ Redwod Company) for their on-going support of NZDFI work.
The E. quadrangulata clonal work is based on the 2016 plantings made at Murray’s Nursery, Woodville. These trees were sampled to evaluate growth strain and other wood properties in very young trees. Seventeen families with below average growth strain and above average growth have been propagated from coppice regrowth of trees felled for wood quality assessments.
The Paparoa trial data has been used to narrow down the family list, and the top ten families selected for further propagation, with a target of 5,000 rooted cuttings to be ready for planting in trials in spring 2021.