A couple of years ago we bought an ‘acacia’ sapling from market – it may well have been the yearly tree market near Tabua – which has grown very fast, is obviously very drought tolerant, as we never water it, and is now flowering.
But, this winter I bought some seeds of the Black Locust, also known as False Acacia from the Agroforestry Research Trust. I planted some a couple weeks ago, in trays, under plastic, and as they germinated really well, I did some research on the internet and discovered that this is almost what we have above the house!
Normal Robinia Pseudoacacia has white flowers, so this is probably Robinia pseudoacacia ‘Purple Robe Locust’ and any seeds are likely to revert to white flowers.
Whatever, they don’t need watering, grow fast, are pretty, they fix nitrogen into the soil and the wood is good quality and hard.
Plants for a Future suggest that the flowers are edible, but as the rest of the tree is poisonous I don’t think we’ll be eating them.
Wikipedia says:
The wood is extremely hard, resistant to rot and long lasting, making it prized for fence posts and small watercraft. As a young man, Abraham Lincoln spent much of his time splitting rails and fence posts from black locust logs. Flavonoids in the heartwood allow the wood to last over 100 years in soil.[3] In the Netherlands and some other parts of Europe, black locust is the most rot-resistant local tree, and projects have started to limit the use of tropical wood by promoting this tree and creating plantations. It is one of the heaviest and hardest woods in North America.
Black Locust is highly valued as firewood for wood-burning stoves; it burns slowly, with little visible flame or smoke, and has a higher heat content than any other species that grows widely in the Eastern United States, comparable to the heat content of anthracite”.[4] It is most easily ignited by insertion into a hot stove with an established coal bed.[citation needed] For best results it should be seasoned like any other hardwood, however black locust is also popular because of its ability to burn even when wet. [5] In fireplaces it can be less satisfactory because knots and beetle damage make the wood prone to “spitting” coals for distances of up to several feet.[citation needed] If the Black Locust is cut, split, and cured while relatively young (within ten years), thus minimizing beetle damage, “spitting” problems are minimal.
It is also planted for firewood because it grows rapidly, is highly resilient in a variety of soils, and it grows back even faster from its stump after harvest by using the existing root system.[6]
With fertilizer prices rising, the importance of black locust as a nitrogen-fixing species is also noteworthy. The mass application of fertilizers in agriculture and forestry is increasingly expensive; therefore nitrogen-fixing tree and shrub species are gaining importance in managed forestry. [5]
So, this may be the tree to grow for fence posts and such – 100 years under soil! Amazing. I will certainly be growing many more of them, as the seeds are germinating quite happily on the potting bench.
We have a couple of self-seeded California poppy plants(Eschscholzia californica), also above the house, which have no relation to poppies. They are just pretty.
Buy any of these highly recommended books and you’ll be supporting a small ecological bookseller and we’ll receive a small commission which we exchange for books for our library. Everyone wins – hoorah!
