In situ regeneration of Pinus strobus and P. resinosa in the Great Lakes forest communities of Canada
Version of Record online: 24 FEB 2009
1996 IAVS - the International Association of Vegetation Science
Journal of Vegetation Science
Volume 7, Issue 3, pages 431–444, June 1996
How to Cite
Carleton, T.J., Maycock, P.F., Arnup, R. and Gordon, A.M. (1996), In situ regeneration of Pinus strobus and P. resinosa in the Great Lakes forest communities of Canada. Journal of Vegetation Science, 7: 431–444. doi: 10.2307/3236287
- Issue online: 24 FEB 2009
- Version of Record online: 24 FEB 2009
- Received 2 February 1995; Revision received 20 July 1995; Accepted 20 August 1995
- Stand classification;
- Stand ordination
Abstract. Two extensive forest vegetation survey datasets are explored, using ordination and classification, for evidence of in situ regeneration by Pinus strobus (Eastern white pine) and P. resinosa (Red pine). Ordination of tree species contributions to total basal area in 320 upland northern hardwood- conifer stands produced distinct stand groups for P.banksiana, P. resinosa, P. strobus and mesic hardwoods in an ascending sequence along the first axis. Quercus rubra (red oak), Q. alba (white oak) and tolerant conifer groups formed segregates from the hardwood complex along the second axis. P. strobus mixes with all other forest types, but P. resinosa is restricted to its own group. Seedlings and trees of P. strobus are more abundant than saplings, which are restricted to the pine and oak forests. Therefore, seed production, dispersal and seedling establishment seem to be less of a barrier to in situ regeneration by P. strobus than subsequent survival and growth.
Canonical correspondence analysis of 170 pine-dominated stands from the Canadian Shield of Ontario, in which tree species variables are segmented into height-class pseudo- species, yielded no linear relationship between environmental features or stand structure and seedling densities of P. strobus. However, total tree basal area appears to impose an upper limit to seedling density on the forest floor. Strong correlations emerged between pine seedling density and understorey vegetation. Stand classification of the understorey vegetation, using constrained indicator species analysis, yielded distinct high and low seedling groups. Low pine seedling density was associated with abundant broadleaved shrubs, herbs and seedlings as well as feathermosses and tolerant conifers. High seedling density could not be ascribed to the presence of seedbed taxa, such as Polytrichum, but is ascribed to the absence of competition and other forms of inhibition in the understorey vegetation and down through the canopy profile. In situ regeneration of P. strobus does, therefore, occur but conditions over the forest landscape are largely restrictive.