You have done your planning ahead with the aim of getting the right tree in the right place at the right time and for the right purpose. Now what comes next? You have selected the site; so now you need to do the groundwork to get that site ready for planting out.
Ideally all site preparation should take place during late winter and early spring so that planting out the seedlings can commence when reliable summer rains occur. Good site preparation means an extra 3 to 6 months growth during the first year.
During your planning process, you will have researched your chosen site, making notes on:
You can now prepare a site plan, marking the location of permanent features such as any changes in soil type, creeks and rivers, land slope, existing vegetation to be retained, roads or tracks for vehicle access during and after revegetation, and new or existing fences to exclude livestock.
During your planning, you decided which method of revegetation you would use
To a large extent, your choice of revegetation method decides which species you will be planting. Based on your choice of species and your knowledge of the preferred habitat of the different species, you can now mark the possible planting location of the different species on your site plan.
Your next step in preparing the site should be to consult with the property owners, neighbours and community groups unless you have done this during the planning stage. The final planting and post-planting operations will go much more smoothly if all landholders and people involved with the tree planting contact each other and discuss future events.
One of the most important acts during site preparation is the removal of unwanted vegetation. So remember to retain the useful native vegetation (some pioneer species may already be present). Also, if the site is prone to erosion eg. a riverbank, consider leaving some cover or grass strips to reduce erosion risk.
It may take some time to remove or kill unwanted vegetation. Therefore, clearing the site should commence some 3 to 4 months before the planned date of planting. Because the soil may be left more exposed during this operation, clearing should take place when there is the lowest possibility of heavy rainfalls so that the likelihood of erosion is kept to a minimum.
If the site is overgrown with woody weeds such as lantana (Lantana camara), giant bramble (Rubus moluccanus) or privets (Ligustrum spp.), hand labour or a small bulldozer can be used to slash the weeds. Regrowth can be sprayed with a translocated, non-selective weedicide to kill the roots, or the stumps can be removed by grubbing them out.
If the site is an old pasture, the grass and herbaceous weeds can be killed readily by spraying with a translocated, non-selective weedicide, such as Glyphosate (refer to product label for application rates). Any newly germinated weeds such as thistles (Sonchus spp.) or Blue Tops (Ageratum spp.), can be controlled by Glyphosate. Leave all dead plant material on the site as mulch. The dead roots will help stabilise the soil until the tree roots take over this role.
Some sites, such as old established pastures, may need to be deep ripped to allow easier penetration of water and growth of tree roots. Always follow the contour during ripping. Never rip steep slopes, stream banks, or creek and river flats. Be aware that soil disturbance will stimulate weed seeds to germinate.
Members of TREAT can obtain established seedlings of many suitable species of trees through the organisation. Contact one of the office bearers listed in the TREAT Newsletter for further information.
Germinating and raising your own seedlings is easy, satisfying and cost effective. Collecting seeds from your local area means you are using species adapted to your local conditions. But remember, permission must be sought whenever you collect, and it is illegal to collect seeds from within protected areas such as National Parks without a permit. Trees growing in remnants of rainforest on private land are a good source.
Regularly monitor the selected seed trees so that you know when the fruit is ripe and ready for harvest. Collect the fruit directly from the trees whenever possible; rodents, insects or fungi quickly damage fallen seed. Keep your collections separate and label them clearly with the date of collection, species name (if known), and locality (for rechecking later if the species name is not known). The method used to extract the seed from the fruit depends on the type of fruit, but all methods attempt to mimic nature. Because there are many different types of fruit, each needing a different method to extract the seeds, seek local technical advice on the best method to use for the species you have collected (see below for some local sources of technical advice).
The seed mix must drain freely, but hold sufficient water to keep the seedlings alive between watering. A coarse, open mix is best. Do not use natural soil because many are too fine for good results. A suitable mix contains 50% coarse sand from freshwater streams, 25% vermiculite or perlite, and 25% peat, sawdust or other organic material. Do not add fertiliser to the seed raising mix.
Use shallow trays and sprinkle the seeds evenly over the seed mix. Cover the seeds with a thin layer of the seed mix if the seed is very fine, such as in Paperbark or Bottlebrush (Melaleuca spp.), or a layer of light, coarser gravel or scoria (about 10 mm size) if the seeds are larger.
Water the seeds immediately after sowing to settle the mix around the seeds. Always use a misting or fine droplet sprinkler head when watering. Keep the seed mix moist throughout the germination period and place the tray in an airy and well-lit location (not in direct sunlight or direct rain). Always raise the seed trays some distance above ground to prevent attack from rodents.
The seed mix can be used to pot the small seedlings into pots for growing on as seedling stock. An alternative mix is one that contains up to 75% composted fine bark and 25% coarse sand from freshwater streams. Add nutrients to the mix at this stage. Use organic fertilisers (eg blood and bone) or commercial slow-release fertilisers at the recommended rates to provide a continuous supply of nutrients for some 4 to 6 months.
Most species can be potted when the seedlings are between 30 mm and 60 mm high, but some larger fruited species may reach 300 mm before leaves are produced. When transplanted, immediately water the seedlings and transfer them to a shade-house or similar sheltered location. After 3 to 4 weeks, the seedlings can be moved into a sunnier position and finally into full sun where they are hardened off ready for planting out at the revegetation site.
QPWS Restoration Services, McLeish Road, Lake Eacham Qld 4884