Winterthorn

Every now and again, I find something really interesting in Business Daily. Yesterday's copy contained an article on the so-called Fertiliser tree, Faidherbia Albida, commonly known as Winterthorn in Southern Africa. Here's the link: http://www.businessdailyafrica.com/-/539444/1171952/-/122lfrcz/-/index.html

Among its many positive attributes, Winterthorn is leguminous. That is to say, it fixes nitrogen in the soil, and researchers have apparently found that the yields of maize and other staple crops improve when planted alongside mature trees. I have always found it difficult to get a straight answer on the real impact of nitrogen-fixing plants on the nitrogen content of soil, but given that Winterthorn needs fairly generous spacing, it seems safe to assume that only a small proportion of nitrogen consumed by the inter-crop will be put back by the tree.

However, there are numerous other benefits to Winterthorn. It forms a useful windbreak for maize and sorghum. It sheds its leaves in the rainy season, which means that high levels of sunlight reach inter-crops during their peak growing season after the rains have finished. By forming a mulch, its leaves reduce soil water transpiration. Unusually, it flowers at the end of the rainy season and therefore provides a valuable forage source for bees at a time of scarcity. Its seed pods are good fodder for cattle and goats, and its timber has a very high calorific content when used for charcoal or firewood.

Indeed, the only drawback to planting Winterthorn in suitable semi-arid eco-zones would appear to be that its leaves are particularly attractive to African elephants. And it goes without saying that elephants and farmers are not the best of friends!