Strategic Level Forest Inventories — Real or Imagined?

Is there such a thing as a “Strategic Level Forest Inventory” and why is it different from other kinds of inventory? I have been told by some that the answer to the first question is “Yes” and the answer to the second question is “… because it is not really reliable enough to be used operationally.”

“We are trying to live in two different worlds and say they are one. We really know there is only one world. There is one forest, one inventory, and a more … or less reliable view of that inventory. “

In much of Canada, we work with large landscapes and have come to the conclusion that we can’t really afford to produce ground sample based inventories. So, what we do instead is rely on well trained photo interpreters to make estimates of forest attributes. In particular:

• species composition,
• height,
• age,
• crown cover (not crown closure but the two are often confused), and/or
• basal area.

While photo interpreters are pretty good at what they do, they are not so good as to obviate the need for additional ground sampling to determine more precisely and with less bias the nature of stand conditions at any specific location, or for that matter on average and across many locations. This lack of inventory precision is deemed acceptable to underwrite strategic decisions — take determination of Annual Allowable Cuts (AAC) in pursuit of sustainable forest management as one such example. While it is good enough to determine AAC, it is not really good enough for determining where the harvesting should be done and to what extent in reality , “… that is an operational decision, not a strategic decision.”

This is all well and good if it were not for the requirement that we practice “sustainable forest management.” How can we even determine whether or not it is sustainable?

“We are going to do what we said we would do in the strategic level plan, just not in the same way that the plan suggested that we should do it. After all, it is a strategic level plan, not an operational plan.”

“We take it that the rules of conduct (those embedded in legislation, regulation, and policy guidelines) will sort things out because we tried to reflect these in our strategic level plan, and what we found from that planning exercise is that we will indeed be practicing sustainable forest management.”

This is a nice story. It is an illusion created by a desire to spend as little as possible on inventory and so too, to justify forest management planning and practices as being both necessary and sufficient to underwrite sustainability. It is planning as a smokescreen to cover our tracks. “After all we went through an in depth planning and analysis exercise and concluded that it could be done.”

We are trying to live in two different worlds and say they are one. We really know there is only one world. There is one forest, one inventory, and a more … or less reliable view of that inventory. To the extent that forest inventories are unreliable, they put us increasingly at risk of making poor decisions and determinations. This risk increases as demands for, and threats to, ecosystem goods and services increase, and as supplies, and the ability to access and manage those supplies, decrease. Misinformation has the potential to drive us into a cul de sac that once in, can be difficult to leave.

Situations have arisen where the strategic level plan says that wood was available for harvesting, when in reality (on the ground) not enough could be found to meet expectations. This was the result as we engaged with the real forest and rules of conduct, not the ones we simulated in the computer. No doubt there have been situations where the converse has also been true, where the plan suggested supplies were limited and yet, in reality, they were not. Either way, our illusion imposes additional costs, and ones that are real. They are proportional to the likelihood that our decisions are faulty, all multiplied by the expected levels of damage or missed opportunity should that indeed be the case.

If we are prepared to defend inventories that are unreliable representations of the forests we wish to use, particularly where we have options to do better, then we accept the risks, and the associated costs incurred by taking those risks, that our practices do not in fact underwrite sustainability and may in fact lead to self inflicted wounds. Time to recognize the real cost of forest inventory that includes those caused by faulty decisions emanating from misinformation.

There is only one forest inventory. To be effective and efficient that inventory must serve both strategic and operational outcomes. No two ways about it!

Ian Moss — Chief Analytics Officer @ Tesera.com