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"Operations
and staff expertise have improved rapidly at the nursery -
we are now in the position to grow more trees and diversify
beyond bluegums."
Simon
Hunter, Nursery and Research Manager.
WHY
DO WE NEED A NURSERY?
The
nursery is an integral component of WAPRES
because it allows us to take our genetically improved seed
and produce vigorous seedlings with superior performance qualities.
Similarly, our stringent quality control in the nursery ensures
greater success in establishing the bluegums in the field.
WHERE
IS OUR NURSERY LOCATED?
THE
FUTURE
WAPRES will market its nursery services to clients
wishing to grow bluegums from genetically improved seed, native
seed or seed supplied by the client. It will also grow other
plantation species such as Pinus radiata and diversify into
new and expanding markets for seedlings. Currently the nursery
is growing host seedlings for truffles and investigating the
possibility of producing Eucalypt hybrids.
WAPRES will continue to grow native tree species
for private orders and giveaways at promotions and agriculture
shows.
GRAPH
1. SPECIES BREAKDOWN EXPRESSED AS A PERCENTAGE OF TOTAL SEEDLINGS
GROWN FOR 2001.
HOW DO WE PRODUCE OUR BLUEGUM SEEDLINGS? 1. GERMINATING
THE SEED
 The
germination process is initiated prior to the seed being sown
to ensure uniform establishment in the seedling trays. This
is achieved by drenching the seed in water and placing the
seed in a germination chamber for 24 hours, where both humidity
and temperature are controlled. Composted
pine bark is used as the seedling media for various reasons.
It is readily available as a by-product and does not harbour
pathogens found in sands and soils. Apart from providing an
ideal media for root development, trays are 30% lighter with
pine bark as compared to conventional mixes of sawdust, sand
and peat. The pine bark is tested several times during the
composting stage and prior to use to ensure that it meets
specifications for a range of chemical properties including
ph and critical nutrient levels.
A
media mixer adds slow release fertilisers and a wetting agent.
The trays, which vary in size from 50cc/cell to 98cc/cell
(depending on the customer's requirements), are mechanically
filled and sown.
2. SOWING
THE SEEDS
 The
seed is sown mechanically using a fluid drill seeder. This
allows for the accurate placing of individual seeds into each
cell. Up to 250,000 seeds can be sown in a day. After
sowing, the trays are stacked on pallets and wrapped under
plastic for two days to optimize temperature and humidity,
which assists in achieving an even germination. Sown trays
are then unwrapped and racked out on the nursery benches.
3. CONSOLIDATING
THE TRAYS
 Additional
seeds are sown in miniplug trays to allow for the replacement
of seedling cells that are empty or contain defective seedlings.
This is done 4- 5 weeks after sowing when seedlings are approx
20 mm in height.
4. IRRIGATING AND FERTILISING THE SEEDLINGS  Water
is pumped from a dam on site and is treated and filtered.
Exact quantities of fertilisers are injected into the irrigation
system from tanks holding the concentrated solutions. The
fertiliser regime is manipulated at various stages to provide
a healthy and hardened seedling.
5. DISPATCHING THE SEEDLINGS Seedlings
are graded to ensure at least 95% of cells contain a plantable
seedling prior to dispatch. Seedlings which do not meet the
seedling specification i.e. height or collar diameter are
discarded. WAPRES uses both its own and contractor's
vehicles for seedling deliveries. Deliveries total around
one million seedlings per week, starting in early June and
continuing until mid August. Deliveries are also made to the
Green Triangle in South Australia.
"WAPRES has seen large growth in the number of genetically
improved seeds it produces each year and now produces enough for
its entire nursery capacity of 6 million seedlings."
Simon
Hunter, Nursery and Research Manager, Treefarms.
WHY
ARE OUR SEED ORCHARDS SO IMPORTANT?
Our
seed orchards are critical to the operations of WAPRES because they allow us to improve the genetic composition
of the bluegums we plant. This means that we can select and breed
trees that provide the most profit for the woodfibre industry,
where financial returns depend upon wood volume, density and pulp
yield.
WHERE
ARE OUR SEED ORCHARDS LOCATED?
WAPRES has a number of orchards located
throughout the southwest of Western Australia.
1. SELECTING
THE PARENT TREES
 Trees
growing in breeding trials which possess genes for rapid growth
and improved wood properties are identified using state of the
art genetic analysis, which is supported by the Southern Tree
Breeding Association (STBA). Scion material (growing tips) from
these trees are grafted onto rootstock and grown in clonal orchards
or the same seed used to grow the selected tree can be used to
create seedling seed orchards. 2. ESTABLISHING
AND MAINTAINING THE ORCHARD
 The
trees in a seed orchard look very different to plantation trees.
The trees are spaced wider and they are routinely lopped to 5
to 6 metres to make seed collecting easier. Application of the
hormone, Paclobutrazol, encourages the reproductive growth of
the trees. This leads to prolific flowering of the trees, allowing
more seed to be produced. A beneficial side effect of the hormone
is that it stunts growth, again making seed collection easier.
3. POLLINATING
THE FLOWERS
 Bees
mostly pollinate Bluegum flowers. However, birds and other insects
also play a role. Encouraging pollinators and avoiding practices
that may harm them is important for maximising pollination and
maintaining seed numbers. By
the natural process of open pollination, bees pollinate the flowers.
Bees will generally work a single tree at a time, pollinating
the flowers with pollen sourced from that particular tree.
The best quality seed is produced by the method of mass supplementary pollination. Flowers are pollinated by hand with pollen collected from selected bluegums. Although this method is labour intensive, the increased number of seed and the extra genetic gain, make it an attractive alternative to natural pollination. 4. COLLECTING
THE SEED
Normally
each capsule will yield 12 to 14 seeds, however it can yield
anywhere between 5 and 50 seeds.
5. BREEDING
FOR THE NEXT GENERATION OF TREES
 To
produce the next generation of improved trees, selected elite
trees are cross pollinated by hand. The flower is covered with
a balloon to ensure it is not contaminated with extraneous pollen
through natural pollinators i.e. bees. Each year, breeding trials
are established using seed from these control pollinations.
After four years of age, the trees grown from these crosses
are assessed on growth and wood density to select the next generation
of parent trees. THE
FUTURE
WAPRES plans to continue to be a leader in the
production of genetically improved bluegum seed. The seed will
be used to ensure the Company's plantations are of the highest
genetic quality possible and will keep it's nursery at the forefront
of supplying the highest quality seedlings to its customers.
Any surplus seed will be sold to domestic and overseas markets.
WAPRES is involved in research aimed towards increasing
yield and wood properties. Secondary breeding strategies will
include resistance to pests, drought and sawlog properties.
GRAPH 1. SEED HARVESTED FROM WAPRES BLUEGUM ORCHARDS SINCE 1999.
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