Rainforest seed tends to ripen over a long period, so our collectors need to be able to recognise when fruits are ripe enough to collect. Multiple trips may also be required to ensure enough seeds are collected. In addition, a large number of rainforest fruits are fleshy, have a high moisture content and rot easily, so they need to be handled with care and processed quickly before the seed is damaged.
Extensive planning is needed to prepare for a field trip. Having a vehicle that is up to the task is just the first step. You then need to pack it with all the items needed for collecting different sorts of seeds, processing and storing them while away, along with things for documenting the process as you go.
Collecting trips are usually aimed at obtaining seeds or plant material of specific species and therefore our collectors go to locations with records of their target species, at a time of year when plants should be in fruit. These means a lot of trips happen in summer and autumn.
Once a target species is identified, an assessment of seed quality and maturity is made with a cut test
. If seeds are suitable, the collection is made and will include a section of plant material including leaves and (where possible) fruit and flowers. The plant material will be used to help to confirm the identification of the plant once it is returned to PlantBank.
To ensure fruit and seeds are returned safely, collections will be packaged and stored appropriately. For fleshy rainforest fruit this will often involve aerated plastic bags and the storage of seeds in cool (but not cold) conditions. Sometimes collections must be made from immature fruits in which case fruit will often be maintained on stems and branches, and seeds will be held in warm humid conditions to help promote ripening. This process must be managed very carefully so that seeds do not go mouldy!
On the collecting trips not only do our collectors get to see the wonderful flowers and fruits of these rainforest plants they often get glimpses of birds and animals that use these plants for food and habitat.
In December 2014 the PlantBank seed collectors were collecting in the Tweed Valley. They were fortunate to see the endangered Grevillea hilliana
, known only from less than 100 plants in NSW, in flower. Some of the remaining specimens are over mature and don’t produce seed but our collectors did find one plant with a good crop of seed developing.
Another spectacular rainforest flower, Pararistolochia laheyana,
was found in the Border Rangers National Park. This species, has become quite common in the areas of Antarctic beech rainforest that had been recently disturbed by storms. While working in the higher areas of the Tweed Valley on 14 December 2014, in the Border Ranges, the PlantBank seed collectors saw the spectacular flower of Trichosanthes subvelutina
. There were no fruits at the time, but collector returned the following August when they were able to make a small collection.
A seed collection trip in January 2017 resulted in the discovery of new populations of two vulnerable species. Macadamia integrifolia,
which was believed to be absent from natural areas in NSW, and M. integrifolia
were both found growing in Mount Pikapene National Park.