NSDNR’s nature-based forestry

Clearcut at Raven Head, Sep 29, 2011

Clearcut at Raven Head, Sep 29, 2011

We have now developed tools that ensure that all harvest treatments are aligned with the nature-based requirements of Nova Scotia’s lands.” – Statement under Goal 13 in the Five-year Progress Report on the 2011-2020 Natural Resources Strategy released Aug 16, 2016 by NSDNR.

I wish it were true, but I don’t buy it. Here’s why.

Statements by NSDNR are highlighted by brown text.

TRIAD ZONING

Four levels will characterize forest management intensities:
forest conservation reserves;
extensively managed forests;
intensively managed forests; and
– forest conversions.

From Nova Scotia’s Code of Forest Practice (Aug 2012)

Comment: Although not explicitly stated as such, this directive, excluding forest conversions which take land out of forestry, involves the application of “triad zoning” to the overall management of NS forests.

–>Key question #1:

What percentage of Nova Scotia’s forested lands does NSDNR envisage in each of the three forest management categories (conservation reserves, extensively managed, intensively managed)?

Here is why that percentage important: in various renditions of triad zoning, extensive forest management is the largest percentage, typically 50% or higher; reserves and intensive blocks are embedded in an extensively managed landscape. If we are following conventions from which the concepts of “management levels” were drawn, we would be simulating natural disturbance regimes on 50% or more of the harvested landscape. So what are the disturbance regimes?

FREQUENT & INFREQUENT STAND DISTURBANCE
From Nova Scotia’s Code of Forest Practice (Aug 2012):

1.1.5 Extensive forest lands will be managed for resource production using techniques that mimic natural disturbances and sustain natural ecosystem structure and function. Management strategies will be based on the provincial Forest Ecosystem Classification (FEC).

Private woodlot managed to simulate natural disturbance regime in the Acadian Forest

Private woodlot managed to simulate natural disturbance regime in the Acadian Forest

–>Key question #2:

Of the lands that NSDNR envisages belong in the Extensive Management category, what percentage is subject naturally to Frequent Stand Initiating Disturbance Regimes and what percentage to Infrequent Stand Initiating Disturbance Regimes?

The answer according to NSDNR:

Infrequent and/or gap disturbance regimes are dominant on 51% of the landbase and develop forest associations typical of the Acadian Forest. These forests of red spruce, hemlock, white pine, sugar maple, beech, and yellow birch originate or establish from successional processes started by an infrequent or rare stand initiating disturbance. They are maintained as uneven-aged forests by gap disturbances in the canopy until the next stand initiating disturbance. Frequent disturbance regimes are dominant on 43% of the landbase and develop forest associations of balsam fir, black spruce, white spruce, jack pine, red pine, white pine, white birch, and red maple. Whether due to edaphic site conditions or disturbances (fire, insects, wind) these forests are predominantly even-aged and unlikely to succeed to longer-lived late successional associations of the Acadian Forest. The remaining six per cent of the landbase has edaphic site conditions that severely limit tree growth and develop the open seral vegetation communities associated with barrens, sparsely treed bogs and swamps, rockland, and severely exposed sites.
Mapping Nova Scotia’s Natural Disturbance Regimes
Report FOR 2008-5 Ecosystem Management Group
Forestry Division, Truro, Nova Scotia
April 2008

Thus, by the logic of NSDNR, harvesting systems that simulate Frequent Disturbance Regimes, i.e. clearcutting, would be appropriate on 43% of the landbase, while harvesting systems that simulate Infrequent and/or Gap Disturbance Regimes would be appropriate on 51% of the landbase. Yet NSDNR has backed away from defining a percentage figure for clearcuts and most harvests continue to be clearcuts while the province claims that “all harvest treatments are aligned with the nature-based requirements of Nova Scotia’s lands”.

HOW SOUND IS THE SCIENCE UNDERLYING NSDNR ESTIMATES OF THE PROPORTION OF THE LANDBASE DOMINATED BY FREQUENT DISTURBANCE REGIMES?
On top of the considerations above that indicate there is an over-representation of even-aged management compared to NSDNR’s estimates of the percentage of Frequent Disturbance Regimes on the Nova Scotian landscape, it is unlikely that NSDNR’s estimate of that percentage (43%) would stand up to peer review. That estimate is given in a NSDNR 2008 document Mapping Nova Scotia’s Natural Disturbance Regimes). This document has not been subject to a rigorous, independent external review as would occur, for example, if it were submitted for publication in a reputable scientific journal.

An internal review of an earlier version of the document revealed by a FOIPOP concluded:

The conclusion that nearly 50% of our provincial forested landscape is prone to frequent stand initiating disturbances is very questionable. – DNR_internal_critique “Obtained through Freedom of Information Request to NSDNR, July, 2006” Accessed at www.novascotiaforests.ca, 2 Dec, 2013

An external review conducted by two academics from Maine and five from Nova Scotia on the 2007 version of this document is reported in Appendix A of a 2012 document “Review of Stora Enso Port Hawkesbury’s Forest Management Practices in the Context of Forest Stewardship Council Certification“. It raises many questions about the 2007 document, most of them not addressed in the final 2008 document, e.g. it notes:

It seems that many of the references cited, or the way in which they are used, are out of context and potentially misleading. There is on overall impression of credible arguments not being made, and of inappropriate (or lacking) citations in support of key assertions. It is apparent that a limited portion of the literature is being mined to support a view that it is appropriate, from a management perspective, to largely ignore the ecological conditions of the past – particularly in terms of dominant forest types and the environmental dynamics and other factors that allowed them to self-organize. This is especially the case of forest-community types dominated by relatively tolerant, late-successional species of trees, and of the role of gap-phase microdisturbance as an important factor affecting older stands. The approach used is not credible.

In short, NSDNR is vague about its application of Triad Zoning to management of Nova Scotia forests and is clearly not adhering to conventions associated with this approach. Clearcutting still accounts for a much larger proportion of harvests – 86% of crown lands in 2014 – than the proportion of the landscape naturally subject to Frequent Stand Initiating Disturbances, even by their own inflated estimate of that proportion (43%).

The claim that “that all harvest treatments are aligned with the nature-based requirements of Nova Scotia’s lands” is simply not credible.

—–
View also



shopify analytics ecommerce