In the second of two broadcasts about more sustainable forestry practices, one of the founders of the Cortes Community Fortes Co-operative talks about the industry’s diminishing harvests in terms that every gardener understands.  (Click here to access part 1)

“Back in the 1970s the justification for logging all the old growth was that the Province was going to be tree farming, to give the public the idea that you’re actually going to be sustainably growing crops off of that landscape each year,” said Ellingsen. 

Every farmer knows that they need to replace the nutrients that they are taking out of the soil, or “pretty soon it will not grow a crop successfully any longer.” 

However the foresters, engineers and everybody else involved in deciding what is a sustainable cut in the provincial forest are not allowing for the reduction of nutrients in the land base with each succeeding harvest. 

“They just work on an assumption that has been touted for years. We can cut down the forest and then as long as we replant at least one tree for each one we cut – or maybe two or three, considering that they will not all get to an age where we allow ourselves to cut them again – we’re still going to be sustainable. Each crop is going to be replaced with new trees. But the thing that is not being replaced is the nutrients that it takes to grow those trees. It’s being gradually drawn down,” explained Ellingsen. 

He said if he didn’t replace nutrients each year in his garden it would take about three years for the soil to become exhausted. After that, he would need to either add nutrients or leave the garden fallow so it can regenerate itself.

“In forestry terms, we’re dealing with a lot longer timeframe, but the dynamic is still the same. Every time you have a new crop of trees on a landscape and harvest it, you’re taking about half of the nutrients that it took to grow those trees out of that landscape and that disappears down to the booming ground and off to the ship or the saw mill, or wherever it’s going,” said Ellingsen.“Over probably three or possibly four rotations you’re going to be exhausting that landscape of the ability and the nutrients required to regenerate succeeding crops of trees.” 

Dr. Suzanne Simard, from UBC, gave an example of soil depletion during her presentation at the Tidemark theatre last fall. There were 12 inches of organic matter in the photo of topsoil of a site she visited 30 years ago prior to harvest. Returning to it last year she found about half that amount of organic matter remained.

“We can’t afford to fertilize our grand forest landscape in BC. The province would bankrupt itself really fast. Talk about a negative input to the provincial economy, boy! Anyway those are the reasons why I, long ago, came to the conclusion that what we’re doing in the province  is not sustainable,” said Ellingsen.

In an old forest, the community of epiphytes naturally deliver nutrients to the ecosystem, but they do not re-establish quickly enough to contribute much within the 50-80 year crop rotation under current forest management practices.  

“Those epiphytes are capable of taking nitrogen straight out of the atmosphere into their tissues and then, as they go through their relatively short lifetime and die and fall to the forest floor … that becomes available to the trees in the forest,” said Ellingsen. “It takes maybe up to 250 years or so before the full range of those species of epiphytes re-establish themselves and start fully pumping that nitrogen back into the system.”

He added that the current practice of eliminating competition when planting “preferred” trees is also detrimental. Whatever benefits saplings might gain by exclusive access to nutrients is overshadowed by the loss of a symbiotic interaction with other species of trees that occur naturally in a regenerating forest. For example, Simard proved that before Aspen trees grow their leafs in the Spring, they receive nutrients through the mycorrhizal network from adjacent conifers. 

“Once the Aspen trees leaf out in the spring and in the summer, when they’re fully leafed out and their  photosynthetic activity is at full bore, then they’re transferring nutrients over to the conifers. Then in the autumn, when the Aspen lose their leaves, the transfer goes back from the conifers to the Aspen trees,” Ellingsen explained.

He said Eastern Vancouver Island is now into its  third or fourth tree harvest. The forests between Victoria and Sayward were initially logged in the late 1800’s and early 1900’s. Most of the giant trees were cut down by the 1950’s and 60’s. Isolated pockets remain, like Cathedral Grove on the way to Port Alberni.

“When I was a young fellow, the assumed harvesting cycle was around 80 to 120 years. Now the Ministry of Forests thinks that the sustainable rate of harvest should be around 60 to 80 years. So it’s creeping down all the time.”

Top image credit: Manure by Rob Bertholf via Flickr (CC BY SA, 2.0 License)

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