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Any clearcuts authorized using the old Forest Management Guides should be rescinded, write Helga Guderley and John Himmelman.
Any clearcuts authorized using the old Forest Management Guides should be rescinded, write Helga Guderley and John Himmelman. - Contributed

Forestry practices have been on the minds of Nova Scotians, particularly those who are faced with the encroaching moonscapes wrought by clearcutting, the dominant harvest method.

A recently proposed clearcut operation in Shelburne County has garnered significant attention.  This harvest has been scheduled despite the conclusions of a government mandated in-depth analysis of forestry practices by Prof. Bill Lahey and a team of experts. 

The Lahey report, released on Aug. 21, suggested major changes in harvest practices on Crown land so that “ecological forestry” would prevail.  Its recommendations echo many made by the Natural Resources Strategy that was accepted by government in 2011 and then dropped in 2016, during the first mandate of the McNeil government.  The Department of Lands and Forestry (DLF) has been studying the report, but has yet to adopt its recommendations.  The provincial government will provide its official response on Monday (Dec. 3).

So where does Nova Scotia stand regarding the implementation of “ecological forestry”?

Over the past decade, the Department of Natural Resources, now DLF, has been developing “ecosystem-based management.” Its stated aim is to provide a scientific basis for harvest prescriptions on Crown land.

DLF biologists have developed an excellent guide to the many types of forests in Nova Scotia. This Forest Ecosystem Classification Guide (Neily, Keys and Quigley ? 2010) shows that our forests are predominantly populated with multi-aged mixed species.  This would seem to indicate that DLF recognizes that even-aged management, i.e. clearcutting, cannot emulate natural events in Nova Scotia forests.  Nonetheless, harvest outcomes are predominantly clearcuts. 

DLF provides the Harvest Plans Map Viewer so that the public (those with internet access) can find out upcoming harvest plans for Crown lands. This shows where and how harvests are to occur.  Clearcuts are the dominant harvest prescription.  They may also be called shelterwood harvest (a “uniform” shelterwood cut, whereby all trees are removed in a two-stage clearcut), overstory removal (a clearcut using a more sophisticated term), seed tree release (clearcut with a scattering of residual trees to disseminate seed) or salvage cut (clearcuts where some blowdown exists).

A brief comment period is available for the public, and generic responses are sent assuring the concerned citizen that scientific methods have been followed to arrive at the harvest plans.  Since the implementation of the digital Harvest Viewer Platform, few if any harvests have been altered stemming from public concerns. Some people have stopped commenting, declaring that Harvest Plans Map Viewer is a “fake” consultation instrument that does not actually provide meaningful dialogue and never changes the harvest prescription.

A harvest prescription is determined using a pre-treatment assessment, which first describes the ecosystem type, site type and forest condition in the targeted area and then uses decision keys to arrive at the harvest prescription.

The Forest Management Guide “prescribes uneven-aged management and non-clearcut harvesting methods when appropriate as a first choice.” However, the most frequent harvest prescription is clearcutting in one form or another.

The Forest Management Guide indicates that soil type, vegetation type, wind exposure, wildlife, geology, tree species, tree size, regeneration, patchiness of stand and “acceptable growing stock” are assessed for each targeted area, making the process systematic and “scientific.”

Some characteristics are fairly easy to quantify (vegetation type, species, size, patchiness and availability of young trees in the understory).  On the other hand, it is more difficult to assess wildlife abundance and to understand the full impact of geology on forest growth.

The Lahey report echoes concerns of DLF wildlife biologists that wildlife habitat is not considered sufficiently during harvest planning.  “Acceptable growing stock” is a qualitative measure based on the utility of trees for sawmills and ignores the importance of crooked or forked trees for wildlife food and shelter.  So why does the use of these data in the decision keys almost always lead to clearcutting as a harvest outcome?

In an addendum to the Lahey report, Robert Seymour, forestry ecologist at University of Maine, indicates “If forest management in Nova Scotia were truly ecosystem-based, using natural disturbance regimes and other ecological science to guide silvicultural decision-making, one would expect the Forest Management Guide to prescribe multi-aged silvicultural systems on the vast majority of the natural forest landscape.  As described below, this appears not to be the case.”

Seymour also states that: “A thorough review of the current Forest Management Guide by the review team and other foresters experienced in practising multi-aged silviculture suggests that the fundamental problem with the Forest Management Guide is that it seemingly preordains an even-aged (single cohort) forest management paradigm in virtually all forest types.  Alternatives are often mentioned but are never required and must meet overly stringent criteria even to be attempted.  As long as foresters follow this guide religiously, clearcutting (complete overstory removal) will likely remain the dominant regeneration practice in Nova Scotia.  In general, decision trees use questionable criteria for stand maturity, appear too eager to establish and release regeneration at the expense of retaining growing stock and do not mandate any sort of structural or compositional retention during final harvests.”

A major problem with many decision keys is that the initial question is whether a stand is overmature.  Stands of hemlock or yellow birch with 100-year-old trees are considered overmature, even though these species can live for 300 to 400 years.

If stands of shade-intolerant hardwoods are considered overmature, one is sent to the regenerate key.  If the stand is mature and the acceptable growing stock is over 10 m2/ha, one is also sent to the regenerate key. In this key, only one of the seven possible outcomes is “let it grow.”

In many decision keys, the assessment of wind-throw hazard is inserted and increases the likelihood of clearcut prescriptions. While the outcomes are named “salvage, overstory removal (stocked or not-stocked) or restoration shelterwood,” they are clearcuts to ordinary citizens and wildlife. Selection management or multi-age silviculture are not outcomes for stands of shade-intolerant hardwoods.     

The analysis by Prof. Lahey and his expert reviewers clearly indicates that the decision keys used to establish harvest outcomes on Crown lands need to be revised.  Only after these revisions will  “ecological forestry” on Crown lands become possible.

Premier Stephen McNeil commissioned this report in response to public concern about forestry practices.  The Lahey report points the way to “ecological forestry” on Crown land.  The McNeil government should heed its advice.

Any clearcuts authorized using the old Forest Management Guides should be rescinded, as they were neither based in science nor ecological.  An immediate moratorium should be placed on any further clearcutting until the government adopts the Lahey recommendations in full.

Helga Guderley, PhD, and John Himmelman, PhD, live in Boutilier’s Point. They are retired biology professors from Université Laval.

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