In Thailand forests are falling from the sky, with the aim to reforest a country which over the last decades has lost nearly half of its forest area. Planes are used to drop little clay bombs filled with seed and compost, the invention of a Japanese farmer who wanted to find an alternative to ploughing, which was less invasive and more efficient.
Is it possible that Australian construction and bush fire regeneration practitioners can utilise this new innovation?
Innovation like this draws on knowledge and experience learned through Agriculture to solve a modern day environmental problem. Aerial seeding of pasture species is nothing new in Australia, with huge areas of QLD aerially seeded with different varieties of buffel and Rhodes grass since the 1960's. However, this form of aerial seeding involves feeding 'naked' seed through a funnel from about 30m above the ground, and relying on the venturi effect created by the plane to deposit the seed where you intend it to go. Studies carried out by the Crop Development Center at the University of Saskatchewan, Canada, show that broadcast methods versus direct drill seeding will result in lower establishment levels and poorer crop yield rates.
Present day aerial seeding is carried out across many regions in Australia, particularly around Goondiwindi QLD because the country is very susceptible to erosion by water.
In construction , it is quite common for large areas of land to be cleared and grubbed, before or during a project. This is a practice which environmental managers try to discourage, preferring a staged clearing approach with staged re-vegetation. However, if the nature of a project demands large scale clearing and grubbing, or there has been large scale deforestation caused by a bush fire, there is the potential for a better re-vegetation outcome if aerial seeding with seed bombs were to be used.
Traditionally re-vegetation in construction is carried out by hydro-mulch trucks, which broadcast a mixture of seed, soil binder, ameliorate and mulch across an area. Whilst this is preferred over 'naked' seeding ,and this method is perfect for small packages of land, it can get very tricky and expensive when used for steep sites, or sites in low rain fall areas where watering the seed regularly isn't practical. By utilising the green bomb initiative, large scale re-vegetation could be carried out with reduced risk of rework, due to better strike rates. The compost would provide the seed with the nutrients it needs for germination, whilst the clay capsule provides soil contact and protection until rain arrives.
Aerial seeding with green bombs wont suit all sites, due to cost or environmental restrictions, however it's a re-vegetation strategy worth some consideration for use in Australia.