Archive

Searching for a silver bullet

March 3, 2022   ·   0 Comments

We’ve got a problem!  My urge is to find ‘the’ solution. It is human nature to search for ‘the’ answer on the assumption somewhere there is a simple means of reversing the situation.

A recent example is The Akira Myrawaki system, an article in the March 2022 issue of Broadview (Alanna Mitchel), a remarkable shift in forestry practices to achieve new forests. Like most innovations, the system proposed is an important ‘new’ approach to reforesting even the ecologically most seriously abused sites, deserts, gravel pits, tar sands, etc. of which there are far too many around the world.

The article was a valuable reminder of various experiences encountered in travels around the world.  The African shamba system was based not only on reforesting Kenyan highlands with introduced conifers but included an early discovery.  Failure of plantations lead to a study of reforestation efforts in other parts of the globe. 

Mycorrhizas in forest soils was found to be essential for trees to grow.  The shamba system in use today consists of nursery beds of top soil, natural fertilizer and a proportion of forest soil derived from existing ecosystems which had been infused with mycorrhizas.

A few years ago a biology colleague at Lakehead University requested pictures of what he called the ‘biological desert’ of southern coniferous plantations. I managed to take a few but it was early in October and on reviewing the ones I had taken caused a realization there was a very colourful understory of red and orange hardwoods.

One of the key feature of the proposed Myrawaki forests was the establishment of a wide range of species which nature was prone to create over time on areas which presumably had been planted to a single species decades earlier.

Nature is remarkably resilient. A visit to a forest estate in the highlands of Costa Rica included an area which had been planted with local species, a bit of an eye-opener. Not only was the plantation a success but the ecosystem that had developed included an understory of a wide range of plant species.

One of the owners was pleased to note that wildlife species which hadn’t been seen for generations appeared to be returning to live under the ‘new’ forest conditions.  Similarly new pine forests in an account of savannah rehabilitation in Gaviotas, over the mountains east of Bogota in Columbia. With new forest cover much of the original understory had returned.

A major concern with the proposed system is in the details of the article.

Examples noted included the planting of several tolerant hardwood seedlings typical of upland forests of tolerant hardwood species of middle North America. More importantly the emphasis specifically was on a mixture of species typical to local habitats.

The development of any ecosystem is the interaction of its various members and the soil on which they were planted.  Nature certainly achieved its purpose with the planting of forest species in desert areas of the Oak Ridges Moraine in southern Ontario.  This was similar to my experience in regenerating an area in Pagwa east of Longlac in northern Ontario. 

Severe site destruction of a white spruce/poplar seed tree cut forest resulted in highly successful regeneration but with little growth of seedlings for several years.  Nature worked on development of shrubs and forest plants which over time rehabilitated soil conditions until now the ecosystem is a mixed forest ecosystem with sixty foot trees including a well-developed understory.

There is no such thing as a ‘silver bullet system’ encompassing the diverse science of forestry world wide. 

Urban forests present a different scene compared to rural areas.  Forest sites of Northern climates can’t be confused with those of the tropics.  Lake bottom sands are completely different from morainic upland conditions.  Cut-overs are a different story to sites destroyed by wildfires. 

The real value of ‘the silver bullet’ is the more general emphasis on site/soil specific conditions and what different species can accomplish working together.

The bottom line is what mankind is able to achieve working in close association with natural processes.

The end result is not so much the result of any ‘new’ system but paying attention to what Nature has been successfully performing for many generations, with or without man’s destructive or even beneficial initiatives.

Readers Comments (0)