Q: I am wondering if you know of any fast growing trees. I need one to be planted under powerlines so no more than 3m in height and will be near the house and pipes so a non-invasive root system would be important. The other tree needs to have height and be fairly bushy for shade purposes and also have non-invasion root systems also. Jenny – Browns Plains
A: A few fairly fast growing trees suitable for planting under power lines include the following, though there are many others that are suitable as well.
- Callistemon. There are very many callistemons that will suit the purpose, with different growth habits (upright, bushy, weeping) and varied colours of flowers
- Grevillea. Consider the many forms of medium sized trees
- Crepe Myrtle. Quite a few flower colours to choose from
- Leptospermum – quite a few species
- Melaleuca – quite a few species
- Tibouchina – ‘Alstonville’ (purple flowers), and ‘Kathleen’ (pink flowers)
Fast growing shade trees are all too numerous to list out. You could consider the following:
- Tulipwood (Harpullia pendula)
- Tuckeroo (Cupaniopsis anacardioides)
- Tibouchina – as above
- Cassia – many species
- Tabebuia – many species
- Eucalyptus ‘Summer Red’ and ‘Summer Beauty’ – (Eucalyptus ficifolia)
- Frangipani
- Crepe Myrtle – as above
The term ‘non-invasive root system’ is a misnomer. If a pipe, whether it be a sewer line or otherwise, has a crack in it (even the slightest crack) and is oozing moisture, a tree root – whatever the tree – will send its feeder roots into that pipe. Roots go in search of moisture. If the sewer line is of the old-type clay pipe, many tree roots will crack the pipe – purely because of their swelling as they grow, and the brittle nature of the clay piping. The crack then oozes moisture, and feeder roots will again find their way in. The modern type pipes do not ‘crack’ – and have sufficient ‘give’ in them to withstand the swelling of tree roots. They do, however, now and again give way at the joins for various reasons (poor join, movement of the soil, etc.). It is never a good idea to plant trees too close to an underground pipe – or even concrete or bitumen structures - whatever the species of tree it may be.
