latest heartwood formation data from spicatum

This is out of the latest ASN Winter 2009 newsletter. As discussed earlier a lot of variation coming through the latest round of coring ...

----------------------------------------------------------
The good oil is in the timing
Jon Brand
Senior Forester
Forest Products Commission

Early results from harvesting of plantation grown sandalwood of different ages have shown significant variations in heartwood percentage, oil concentration and oil quality.
There also appear to be large differences between the different grades of wood within trees and also between plantations of different ages.
In the last two years, the Forest Products Commission (FPC) has harvested Australian sandalwood (Santalum spicatum) trees aged 8-26 years from different plantations in the south-west of WA. Each plantation was established in a similar manner, with the sandalwood direct seeded near 1-5 year-old jam trees (A. acuminata typical variant).
Each of the sandalwood trees were measured for height, bole length and stem diameter. The trees were removed from the ground using a 4WD vehicle and a chain. Small roots that broke off were also extracted from the ground using a pick and shovel. After harvesting, each whole tree was weighed on site and then de-barked using a pressurized (3000 psi) water de-barker. After de-barking, the trees were cut into small sections, and grouped into five different wood grades:
1.Butts (ground level to 150 mm away from centre of butt)
2. Roots (all root material)
3. 1st grade (stems > 40 mm in diameter)
4. 2nd grade (stems 20-40 mm in diameter)
5. 3rd grade (stems 10-20 mm in diameter)\

From each tree, a cross-sectional ‘biscuit’ of 10-20 mm in thickness was taken from each of the five different grades.
From each biscuit, the fresh weight, air-dry weight and the amount of heartwood were measured, and the oil concentration determined using solvent extraction.

The amount of santanol within oil was also determined using a gas chromatography flame ionisation detector (GC-FID) and a mass-selective detector (GC-MS).
The FPC aims to provide more detail from this study within the next 12 months, and some of the areas of interest will include: (1) the relationship between total commercial air-dry weight and stem diameter; (2) the proportional weights of different grades of wood within a tree; (3) heartwood percentage, oil concentration and oil quality between different grades of wood and between different tree ages; and (4) a general comparison between plantation wood and wild wood.
The results will help sandalwood farmers determine the best time to harvest and give an indication of what oil could be expected from the different parts of the tree.


----------------------------------------------------------
Caring For Country Project
Developing sustainable production systems, resilient to climate change

Predicting tree growth, carbon balance and water use in the Avon – an update on CSIRO work in the AVONGRO Caring for Country project
Don White, Jenny Carter, Tammi Short and Monica Durcan

Since January CSIRO Sustainable Ecosystems have been collaborating with AVONGRO on a large project with funding from the Federal Government through the Caring for Country program. One of the major impediments to adoption of trees is uncertainty about growth rates, carbon balance and other values of trees including changes to hydrology and biodiversity. Our aim is to reduce this uncertainty be undertaking some targeted measurement and combining this with existing knowledge to build a web based tool for quantifying the growth, carbon and water balance and biodiversity outcomes of tree planting for large parts of the Avon catchment.
Our first task is to calibrate our models of tree growth, carbon sequestration and water use for local species and conditions. This is by far the most important part of the project as we must make every effort to reduce uncertainty associated with these predictions. With the help of Helen Job (Brushwood Growers), Bethan Lloyd (Australian Sandalwood Network) and Tim Emmott (Oil Mallee Association) we selected sites to cover the range of climatic conditions, soil types and stand age of oil mallees, sandalwood and brushwood plantings in the region.
Measurements got under way on May the 4th and will continue until mid June. A team that includes Dwayne Durcan, Tristan Job and John Larmour (CSIRO, Canberra) have been measuring trees in three plots established at each sites and collecting soils using a drill rig and plastic push coring system. We are focussing our measurements on Sandalwood and Brushwood as we already have access to a good oil mallee data set through John Bartle at the Department of Environment and Conservation. In June and July we will visit a small number of sites to destructively sample trees. We will use this data to establish relationships between biomass and the simple growth measured we are collecting at the other sites.
Although our focus is on productivity we couldn’t resist the opportunity to make some physiological measurements on the parasitic Sandalwood and one of the hosts. Just before dawn on March 9th, we collected shoots from sandalwood and jam trees at Bert and Norma Wansborough’s place near Beverley. We took the shoots back to River Cottage on Avon Terrace where we repeatedly measured their water status as they dried out over more than 24 hours. These measurements tell us about the way plants will respond to drought and the level of water stress they can endure and still continue to function. Since 1991 we have made similar measurements on species range from environments spanning Australia from the wet forests of Victoria to the dry eastern fringe of the wheat belt. This data has provided important insights into the way Australian tree species cope with drought.