Establishment of Wattle
Essential planting, pruning and growing tips for the two recommended methods for wattles.
Clones grow very fast, so you need to blank within three weeks after planting if mortality is over 10%.
Thinning is a problematic task as the clones are very uniform.
One of the significant disadvantages of growing wattle is that it appears to be so easy. This has led to widespread use of inefficient practices, resulting in poor yields of bark and timber.
The forestry industry has come a long way over the past years, so there is no reason for the poor yields. All it takes is good management practices.
The seedling method
This is based on using selected seeds sown in a nursery to produce seedlings, which are then planted in the field.
Site preparation: The aim is to provide the most suitable conditions to stimulate tree growth. This should commence as soon as possible after a clear felling, since any delay results in unproductive land.
After burning the brushwood, start the pitting process: 1.5m apart in the row, by 3m inter-row. This gives 2,222 seedlings per HA.
Dig the pits to a depth of 25cm by 25cm wide. This is one of the most essential operations for young seedlings to get a good start.
Planting: The best results are achieved by planting in the rainy season, October to February. Later planting can be successful if the seedlings are watered with 2L of water at planting. The use of gel at planting is recommended, but we advise you to mix it with a bit of soil in the pit.
Obtain your seedlings from a reliable nursery. These seedlings must be 15 – 20cm tall and have been hardened off in the nursery. Make sure to water them well before taking them out into the field.
When planting, firm the soil around the seedling plug; pressure on the plug can cause J-rooting. If conditions are dry, apply 2L of water after planting, if no rain within two weeks after planting, re-water.
Blanking: Only blank if your mortality rate is over 15%. It is important to blank within four weeks of planting; otherwise, the seedlings will not catch up to the original plantings.
Tending: Keeping your seedlings weed-free for one year, this will stimulate growth, form and ensure that your site is fully utilised. Speak to your chemical rep about the details of the herbicide application. Use of a wind box is recommended.
Do not prune minor side branches, as this affects the tree growth. When pruning, always leave a stub 30 – 40cm long to prevent the entry of gummosis on the main stem.
Pruning in winter is recommended. Use a small gang of skilled labourers. Close supervision is essential, and secateurs should be used. Severe mirrid damage may necessitate the step to be carried out again.
Thinning: The object of this is to remove weaker trees to leave a uniform size of 1500 stems per HA. This is done when the trees are 3 – 4 years old, and the method used is a 10m rope between two rows. The target is to leave 9 trees; a count of 6 + 3 or 5 + 4 or 7 + 2 would be acceptable. For poorer sites, it is recommended that trees be reduced to 8 trees.
No further work is required after year 4 in your plantation.
To start, we must recognise the work done by the four sponsors of the wattle breeding programme, namely NCT, NTE, TWK and UCL, together with Julian and his team at the ICFR.It all started when the rust hit our industry some six years ago. Wattle cloning is some 25 years behind gum, but a start has been made, and the first clones are showing promising results.
Here again, as for the seedlings, the process starts with a good pit. The one difference is that the spacing is 1.85m apart in the row and 3m inter-row, which gives 1800 clones per HA.
The choice at this stage is SP644 and AF1, as they are rust tolerant, and FW54 is frost tolerant.
Planting: Ensure your planting team is well trained and that good supervision is required as you have spent a lot of money on the clones. Ensure you give them the best chance by following the same method as your seedlings.
Blanking: As your clones grow very fast, you need to blank within three weeks, but only if you have a mortality exceeding 10%.
Tending: As per your seedlings, keep them clean for one year, because they grow so well you might get away with one less weeding.
Remember, from the beginning of December to be on the lookout for the dreaded mirrid. They seem to enjoy fast-growing clones.
Pruning: Remember, leaf material is the food provider for the tree to grow. The operator’s mindset must be to leave as much foliage on the plant as possible. Never over prune!
Train and retrain, as the skilled operator moves down the tree line, making sure he only takes out branches competing with the main growth tiller. These branches usually appear as double leaders or lower branches, curving upwards and threatening to surpass the growing point.
Thinning: This is a problematic task as the clones are very uniform, so selection is not easy but needs to be done to reduce to 1500 trees per HA at 3 – 4 years using the same spacing method as for the seedlings: 10m rope leave nine trees.
Controlling pests
Mirrid: When mature, this insect has a distinct yellow/gold spot on its back. The young mirrids are green and unable to fly. They are shy and quick and challenging to find, but all visible damage on the young growth of trees from 1 – 2 years is caused by the mirrid.
Control this pest before your trees show too much damage. Badly infected trees will recover, but the growth can be reduced by at least a year.
Even moderate damage will create extra work and cost because of corrective pruning needs. Be on the lookout, as chemical application is the only effective control method.
General: Storms, such as hail and severe frost, can cause damage. If you are uncertain of what follow-up needs to be done, request help.
Suppositree: The use of this systematic insecticide tablet is recommended at planting. Contact your nursery manager if you are unsure of any of the above comments.By Friedel Eggers.
On behalf of Sunshine Seedling Services.
