GREATER FUNDY ECOSYSTEM RESEARCH PROJECT

UNB Faculty of Forestry and Environmental Management

Forest Management Guidelines to Protect
Native Biodiversity in the Fundy Model Forest

Executive Summary

Studies in and around Fundy National Park indicate that overmature forests provide critical habitat features for Northern Flying Squirrel (Photo: Parks Canada)

Biodiversity is simply the variety of life and the processes that support it. Scientists usually characterise biodiversity at different scales: the gene, the species, the community and the landscape. All these scales interact to produce what we know as the "diversity of life".Such scales indicate that maintaining biodiversity is a monumental task.. The area of the Fundy Model Forest has a characteristic native biodiversity. At the genetic level, for example, stands of Red Spruce trees have different characteristics from neighbouring stands only a few kilometres away. The species level - which is best known - is characterised by 42 species of mammals, about 250 species of birds, about 1000 species of vascular plants and an unknown number of insects and other life forms. These species naturally form communities which we refer to by such terms as "Upland Sugar Maple forest" or "Lowland Spruce Forest". In turn, communities are a product of bedrock, topography, slope, climate and disturbance history. The landscape patterns are delineated at different scales such as "ecoregions" or "ecodistricts".

COARSE-FILTER AND MANAGEMENT PLANNING LEVEL GUIDELINES

Patch sizes and disturbance regimes - Forests should be managed as either gap or stand-replacing disturbance regimes. This duplicates the historical disturbance pattern for that community type. The division into disturbance regimes should be done first at the ecodistrict level, which accounts for climate differences and enduring landscape features. Secondly, the forest should be subdivided into ecological units with an aim to maintain forest types that exist because of gap-type disturbance.In all gap-type stands, the aim should be to maintain a predominantly closed-canopy cover, a mixed-age distribution of overstory trees and sufficient regeneration to restock the forest. This can be accomplished by selection cuts. For forests managed under a stand-replacing disturbance regime, the operating patch size should be between 375 to 500 ha. However, this should not mean that yearly cuts of that size be conducted. To approximate natural patchiness, the 375-500 ha blocks should be cut over a period of 10-15 years, which would allow working cuts in the range 25-50 ha.

Guidelines for the amount of tree removal on a watershed are being developed. It has been shown that the hydrology and nutrient quantity of a watershed changes with disturbance and we hope to present this relationship in the future.

Connectivity - A network of forested connections needs to be maintained across the Model Forest landscape, with a minimum corridor width of 300 meters and maximum corridor length of 3 km. The forested connections should have a closed canopy forest (minimum 35% crown closure) of any species, with a minimum canopy height of 12 meters. From preliminary research, it appears that selection harvesting will meet the requirements of connectivity.

Water quality and habitat conservation should be
practiced through riparian zone guidelines
(Photo: G. Forbes)

Stream side buffers - The GFE research group supports the direction and content of the Watercourse Buffer Zone Guidelines for Crown Land (see text). However, the steep river valley slopes of the FMF present an additional concern for water quality in the area. We recommend that these steep valley slope areas represent unique and sensitive conditions that should be specifically identified in buffer zone guidelines. A general rule should maintain the current buffer setback of 60 m but beginning at the top of the valley (instead of the shoreline), at a point where the slope is less than 20%. Forest harvest activity would follow the guidelines established within the 60 m buffer, except that no cutting or very controlled cutting should occur within 5 m of shorelines.

Mature-Overmature forest classes - A minimum of 12% of each stand replacing community type (except regenerating and non-forest communities) should be maintained in a mature-overmature age class; 4% should be in the overmature age class. On an ecodistrict level the mature component should exceed the minimum patch size of 375-500 ha. For selection cut forests, mature forests should have a minimum canopy crown closure of 60 %.

The contribution of plantations to mature habitat objectives is possible if they :

• are comprised of native species that are characteristic of the ecozone,

• meet the maturity window for the species,
• meet stand level guidelines for snags and coarse woody debris, and
• have at least 5% other species in the forest canopy.
• in total, plantations of non-native or non-site species should not comprise more than 5% of the total area of the ecodistrict.

Network of protected areas - We recommend that a network of protected areas be established in the model forest to protect rare, unique and representative species and features. These protected areas should be off limits to any resource extraction except:

1. Sustainable, non-motorised recreational hunting and fishing, which may be allowed in areas where they are currently being practised (e.g. Fundy coastal ravines [allow sporadic fishing, except for Atlantic Salmon] and Fundy upland bogs [allow Moose hunting])

2. In some of the forested sites, some form of limited extraction may be acceptable as long as it:

Fundy National Park (Photo: G. Forbes)

a) excludes the harvest of Hemlock b) reflects existing natural disturbance regimes (e.g. selection harvesting in tolerant hardwood stands) c) maintains late seral forest in areas where it presently exists d) respects stream buffer zones, and avoids areas hosting rare or uncommon plants. Management plans for timber extraction and road design within the watersheds encompassing the protected areas will be necessary to integrate the protected area into the working landscape, and to improve the role of the protected area as an "eco-bank".

FINE-FILTER AND OPERATIONAL LEVEL GUIDELINES

Coarse woody debris - Intensive forest management practices tend to eliminate large pieces of decaying wood from the forest. Tree limbs and tops should be left on site after harvest. On all conifer dominated or mixed-wood managed sites or stands, there should be a minimum of 200 pieces/ha of coarse woody debris (average piece diameter greater than or equal to 10 cm) and a minimum total of 10m3/ha throughout the rotation of the stand.

Retention of snags - In intensively managed forests, a lack of suitable numbers and types of large decaying or preferred nesting trees often limits species that need cavities. Forests can be best managed for cavity nesting species of birds by selection harvesting techniques. After commercial timber is removed during the first intervention, the best management option for cavity nesters is to leave a minimum of 10-12 snags (defined as standing dead trees, preferably greater than 20 cm dbh (diameter breast height)) per hectare for feeding, plus 12-15 live, or partially dead, mature Aspen or Beech (in the absence of Aspen or Beech, Maple and Yellow Birch may be substituted) with minimum dbh of 25 cm to be used for nesting. Subsequent interventions should maintain those numbers and ratio and consideration must be given to regenerating young trees as well. Single snags or live trees in clearcuts less than 4 ha. in size may be useful as feeding and nesting trees for certain species of cavity nesters. Live Aspen, Beech, Maple or Birch are preferred over conifer species. Trees should be mature, with a minimum dbh of 25 cm. Clumps of trees are preferable over single trees. The minimum number remaining should be no less than 12-15 single trees per hectare and, in any situation, more is always better than less.

Snags provide nesting and feeding habitat for many wildlife species such as mushrooms, beetles and woodpeckers. (Photo: G. Forbes)

In larger clearcuts (> 4 hectares), managers should pay special attention to leaving scattered clumps of live trees - both mixed deciduous and mixed coniferous. Large clumps are always better than small clumps but a minimum clump size should be 25 m2. In forest clear-cut operations, managers should have knowledge of what there is in terms of potential nest trees (i.e. live Aspen and Beech with 25 cm dbh) and snags (i.e. dead trees with 20 cm dbh) as well as the amount of commercial timber.

In cuts less than 4 hectares, 10-12 potential nest trees and 12-15 snags should be left per hectare. Managers should pay special attention to leaving clumps of trees rather than single trees. Where dead, leaning and down trees do not present a hazard or otherwise interfere with selective timber removal, they should be left undisturbed as an important component of the forest ecosystem.

Improvements to plantations:

Options for existing plantations:

• Overall, plantations of non-native species, such as Norway Spruce, or species not normally forming pure stands in the ecodistrict (e.g. Jack Pine along the Fundy Coast), should not cover more than 5% of the total area of each ecodistrict. Plantations of non-native species or species not normally forming pure stands in the ecodistrict should not be included in inventories of old age class forest types. For example, Norway Spruce can never be considered a substitute for Red Spruce.
  
  
• Plantations can meet mature habitat requirements by letting the plantation age to the maturity window for that particular forest type. The plantation can then meet the criteria for mature habitat, with the following restrictions:
  
  a) the plantation should have at least 5% of canopy tree species that are other than the dominant planted species; b) the plantation should meet the guidelines for coarse woody debris and snags contained in this document (i.e. minimum of 200 pieces of coarse woody debris per hectare and 10 m3/ha., average diameter of pieces greater than or equal to 10 cm). This requirement may be met by early thinning or girdling of trees;
  c) the plantation should have a minimum canopy closure of 60%.
  
  
• Retain as many tree species as feasible during thinning operations.
  
  
• Replant Aspen and Poplar in clumps within maturing plantations for their use by cavity nesting species
  
  

For new or planned plantations:

• Follow snag and clump guidelines, retaining Aspen, Poplar and Birch trees where possible.
  
  
• Retain coarse woody debris
  
  
• Limit crush-and-burn site preparation in order to retain coarse woody debris
  
  
• Retain strips or clumps of competing species during herbicide or thinning operations
  
  
• Use native species only
  
  
• Reflect the site's ecological classification by not converting mixed stands into softwood or hardwood (i.e. plantations on converted sites are not eligible).
  
  

Habitat needs for threatened species - Population and habitat objectives will be developed for these species in the near future.

Special status tree species -Tree species that are uncommon or rare due to human activity should be retained in forests by limiting their harvest and creating the conditions needed for regeneration. The identified species are Eastern White-cedar, Eastern Hemlock, Bur Oak, Red Oak, Basswood, Butternut, Ironwood, Black Cherry, and Black Ash. Red Spruce and American Beech are common but require selection harvest to promote regeneration. The identification and regeneration of disease-resistant trees for American Beech is also critical.

Roads - An unplanned consequence of forestry is a dramatic change in access through road networks. Roads allow increased legal and illegal hunting, fishing and other harvest. They also fragment habitat and allow the spread of disease and exotic species. Road networks should be at a low density, avoid crossing water and be positioned so as to limit access to unique sites. We recommend a target road density of less than 0.58 km of road per km2 of land. As many roads as possible that are not required for ongoing silviculture should be temporarily closed using embankments and boulders which eliminate or decrease vehicle access. Road networks should avoid loop roads and promote cul-de-sac roads.

Back to Table of Contents

The UNB Forestry Home Page