Site Preparation

A few weeks before a site is planted, the landholder or a local contractor ploughs a series of riplines: deep cuts a metre or so into the soil. Although the ripline closes straight up again, it leaves a weakness in the soil that will encourage the young seedlings to root rapidly and deeply.

It has only a couple of months to be ready to withstand the heat of summer and, if the roots are deep enough already, the tiny amount of moisture remaining in the subsoil will be enough to see it through.

Planting

We plant in Autumn, Winter and early spring, whilst there is still moisture in the soil before the planting day the site has been prepared and the seedlings selected, so it’s time to get our plants in the ground and acclimatized before the heat of summer.

For the Regent Honeyeater team and the army of volunteer planters, this is the highlight of the year: the time when everything comes together.

The main planting team splits into two halves: diggers and planters.

Although we have sprayed the weeds and cut a rip line, the top layer of the soil is full of thousands of weed seeds and as soon as it rains, the seeds will germinate and before too long they will be big enough to out-compete our seedlings, or at least seriously retard their growth. A question often asked is why are weeds so good at this? The answer is because that’s what a weed is: a plant that has the ability to out-compete other plants, especially in disturbed environments.

So with mattock and shovel, we scalp off the top few inches of soil, and with it the majority of the weed seeds. Years of planting experience have demonstrated that best results are obtained by scalping an area of about two-thirds of a square metre. We are as unfortunately, removing what little good topsoil remains after decades of clearing, heavy grazing, and rabbit damage — but our native plant species have spent millions of years learning how to cope with Australia’s barren soils and can thrive on them. It’s hard work scalping off the weed infested topsoil with mattock and shovel, but our long-term success rates show that it works.

When it comes to planting it is important to extract the plant from the tube as gently as possible. The less we can disturb the root system, the faster the little plant will adapt to its new location — and within a month or two it will have to deal with the heat of summer, so it needs all the help it can get.

The best method is to turn it upside down and tap the edge of the pot smartly against something firm (such as your knee). With a little practice, you will find that most seedlings pop straight out of the tube with the root system intact. When we plant remember to be gentle to keep that root system intact. The general rule is to make sure that the plant is level with the soil surface — if it is below the surface level it gets waterlogged or dies of collar rot; if it is sticking up above the ground, it dries out and dies as soon as the warm weather arrives. However there are always exceptions to the rule and if a plant has different requirements, we will change the planting depth accordingly.

Lastly we fit the treeguard. The guard helps conserve moisture and protects the seedling against rabbits, hares, and kangaroos — grassland species like hares love to nibble young trees right down to the ground, often ignoring tasty-looking grass nearby. The guard needs to be anchored firmly: kangaroos and cockatoos can easily pull out treeguards if they are not weighted down; the roos like to get at the tasty young plant, the cockies seem to do it just because it amuses them!

This is why we need that generous pile of clean, weed-free soil the digging team left: we use it to cover the treeguard all around to about one-third of its depth.

Over the next few years, the treeguard not only discourages hungry herbivores, it also protects the seedling from the elements and functions like a tiny humidicrib, collecting dew and retaining moisture in the soil for baking hot summer days. Being made of cardboard, it will gradually break down and by the time the young tree is three or four years old and growing strongly, the guard has rotted away to nothing.

Why not use plastic guards and stakes? Wouldn’t it be quicker and easier that way? Yes it would, but it creates litter that needs to be cleaned up in future years, and there is always a small gap between the bottom of a staked treeguard and the soil surface which allows the hot winds of summer through, resulting in less soil moisture and a higher failure rate.

Overall, our planting technique is slow, sometimes tedious, and requires a great deal of physical labour. That effort, however, is amply repaid by extraordinarily high success rates. We aim for 100% success each time we plant, and often come remarkably close to it. After all the planning and seed collection and propagation in the nursery, and the ripping and spraying and fencing, and then the digging, planting and guarding, the young trees and shrubs are on their own. Even in bad years, nearly all of them survive and go on to lay the foundations for a healthy, rejuvenated ecosystem.

Improvements To Our Planting Technique

Over the past decade we have established a planting technique that works very well, but it would be great to speed up the process and make it easier on people, especially the younger students.

Trials with various planting implements gave some success, but results were unpredictable and mostly poorer. We are still in favour of mattocks to loosen the soil and ensure good contact with the seedling roots. The bottom line is an absolute need to maintain our high success rates!

Thorough ground preparation and weed spraying certainly helps. Recent trials with double ripping 15-20 cm apart were very promising, so we intend to use a twin-tyne ripper wherever possible this coming year.

One significant trial last year had two school classes planting together instead of the usual one group at a time.

The 50 students worked together like clockwork, planting a remarkable 905 seedlings and covering well over km! The speed of such a bigger scale operation gives everyone a tremendous sense of achievement and we’ll take that approach routinely now, whenever we have sufficient adult supervision.

With more of our plantings sites on the lower country in recent years, we have been confronted by heavy clay soils that are so much harder to plant in. So we have encouraged our volunteers to work in small teams to find the most efficient methods and tools to deal with the issue. Last Spring they used a combination of Picks, Hamilton tree planters and Mattocks to make small holes, and imported friable soil from close by to seal the seedling in the ground. The results have been very heartening even in cracking clays and dry weather!

We also needed to change tour tree guarding procedure, as burying guards in the ground would have pooled too much water and killed the seedlings. We settled on 750mm wooden stakes to hold our usual 2 litre cardboard drink containers, and it was a great to discover that the protruding stakes seem to have an added benefit – they’re robust enough to deter kangaroos and wallabies from browsing our seedlings!