Forest Landscape Baseline No. 1 Brief Progress and Summary Reports 1993

"WHITE PINE REGENERATION IN FRAGMENTED AND NATURAL OLD-GROWTH
PINE STANDS IN TEMAGAMI, ONTARIO"

Introduction

Less than 1% of the world's original old-growth white pine (Pinus strobus L.) forest remains (AFER 1993a) and many of those remaining are still unprotected. Ontario's and perhaps the world's most significant known concentration of unprotected ancient white pine forests is located in the Temagami region (McAndrews 1978, Quinby 1991, AFER 1993b). Only three of 30 identified ancient pine stands in this region are legally protected from logging. Those that are protected don't include the largest and most viable stands. Many of the unprotected stands have been fragmented by logging and many are too small to be self-maintaining. In addition, fire suppression in these forests since the early 1900's has significantly reduced the success of white pine regeneration. The purpose of this report is to assess and compare white pine regeneration in Temagami's ancient white pine stands with respect to the effects of logging and stand size. This analysis represents the first attempt to understand the population integrity of white pine populations in ancient forest stands, and in part, will provide the scientific foundation for the development of a conservation strategy for these endangered forest ecosystems.

Methods

Over the course of the 1991 and 1992 field seasons, 16 of Temagami's ancient pine stands were sampled. Eight of these stands have been directly affected by past logging activities (fragmented) and eight have not (natural). Fragmentation resulted in the modification of natural stand boundaries - the interior of the fragmented stands remains unlogged. Regeneration is here defined as individuals between the ages of one and 65. All white pine regeneration encountered in 1 x 1 meter quadrats spaced at 6 meter intervals along transects were aged by counting branch whorles. In each of the 16 stands, 21 meters of transect were sampled for each hectare of forest and transects were distributed according to the relative amount of slope, hill and flat topography present within the stand. In total, over 6,800 1 x 1 meter quadrats located along more than 41 km of transect were assessed for white pine regeneration. The density of regeneration was standardized to eliminate the influence of variable seed bearing tree densities from one stand to another so that the influence of logging and stand size could be evaluated. This was accomplished by expressing regeneration density for each stand relative to each tree over 140 years of age present within the stand.

Results

Table 1 - Standardized White Pine Regeneration Density in Natural Old-Growth Pine Stands in Temagami, Ontario

Table 2 - Standardized White Pine Regeneration Density in Fragmented Old-Growth Pine Stands in Temagami, Ontario

FIGURE 1 - Mean White Pine Regeneration Density in Unfragmented (natural) vrs. Fragmented Old-Growth Pine Stands in Temagami, Ontario

FIGURE 2 - Mean White Pine Regeneration Density in Three Classes of Unfragmented (natural) vrs. Fragmented Old-Growth Pine Stands in Temagami, Ontario

FIGURE 3 - Relationship Between White Pine Regeneration Density and Stand Size in Fragmented Old-Growth White Pine Stands in Temagami, Ontario

FIGURE 4 - Relationship Between White Pine Regeneration Density and Stand Size in Unfragmented (natural) Old-Growth White Pine Stands in Temagami, Ontario

Ecological Interpretation

On average, white pine regeneration density is almost four times higher in Temagami's natural (unfragmented) ancient pine stands compared to the fragmented ancient pine stands (see Figure 1). In order to determine if the 900 ha natural stand may have a disproportional influence on the mean regeneration density for natural stands, it was removed from the mean calculation the results of which are presented in Figure 2. This figure shows that for all three stand size classes, white pine regeneration density is much higher for the natural stands compared to the fragmented stands even with the 900 ha stand excluded.

Theoretically, the larger an ecosystem is, the more capable it is at maintaining itself. To test this theory, white pine regeneration can be used as an index of ecosystem maintenance and can be related to stand size. The curve presented in Figure 3 shows that for the fragmented old-growth pine stands, no such relationship between regeneration and stand size exists. However, the curve presented in Figure 4 shows, in general, that as the size of natural stands increases so does regeneration density thus supporting the theory that larger ecosystems are more capable of self-maintenance.

Further work focussing on whether stand shape, internal stand topography and external seed sources have an influence on white pine regeneration in these stands must still be done.

Policy Implications

There is no doubt that unfragmented or natural old-growth white pine stands in the Temagami region are regenerating much more successfully than stands of this type that have been fragmented by logging. For these fragmented stands, it is likely that clearcutting, resulting in the removal of a portion of the ancient pine stand, has reduced the long-term viability of the stand's white pine population by removing a significant seed source. If the viability of the white pine populations in Temagami's endangered ancient pine stands is to be maximized, no more cutting of white pine in these stands or adjacent to them for timber production purposes should be permitted. The buffer width required to protect white pine regeneration processes in these stands needs to be carefully addressed in a scientific manner. Until then, protective buffer zones (no cutting) at least 500 meters in width should be left around all of Temagami's ancient white pine stands.

Results from this study also show that for natural ancient white pine stands, the ability for self-maintenance increases as the size of the stand increases. The same is not true for those stands that have been fragmented by logging. Thus special effort should be made to protect the largest natural stands as soon as possible for their value in studying and unlocking the secrets of natural regeneration. This information can then be applied to maintain the smaller and more fragmented ancient pine stands.

Because fire was a natural component of the renewal of these stands until the early 1900's, it will be particularly important to mimic the effects of fire if these stands are to be ultimately maintained. Contrary to traditional forestry theory, most of the fires in these ancient pine stands have been non-catastrophic in nature (Quinby 1991). Techniques other than logging and planting should be used to facilitate the regeneration of white pine in these stands. Research to test and develop such techniques should begin as soon as possible.

References

Ancient Forest Exploration & Research (AFER). 1993a. The Status of Old-Growth Eastern White Pine Forest in North America. Forest Landscape Baselines No. 2, Powassan, Ontario. 4 pp.

Ancient Forest Exploration & Research (AFER). 1993b. Characteristics and Preliminary Definitions for Old-Growth White and Red Pine Forest. Forest Landscape Baselines No. 3, Powassan, Ontario. 4 pp.

McAndrews, J. H. 1978. Forest composition of Ontario in the mid-Twentieth Century. Unpublished Manuscript, Dept. Botany, Royal Ontario Museum, Toronto.

Quinby, P. A. 1991. Self-replacement in old-growth white pine forests of Temagami, Ontario. Forest Ecology and Management 41:95-109.

Produced by Ancient Forest Exploration & Research, R.R.#4, Powassan, Ontario P0H 1Z0 phone/fax (705) 724-5858; A progress report of the "Conservation Strategy for Ancient White and Red Pine Forests in the Temagami Region of Ontario" Project; written by P. A. Quinby, field supervision by P. A. Giroux and L. Hudson; Funding provided by Earthwatch, Dr. J. Hackney,

Dr. A. Stone, the Temagami Wilderness Fund, the Temagami Region Studies Institute, the Laidlaw Foundation, The Royal Canadian Geographical Society, Algonquin Canoe Store, the Madawaska Kanu Centre, the Charles Frederick Fell Charitable Trust, the Boland Foundation, the Helen McCrae Peacock Foundation, Smoothwater Outdoor Centre and the Algonquin Wildlands League

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