I am studying the spatial pattern of reproduction in trees.  Through a combination of increment coring and DNA fingerprinting I will be able to determine parent-offspring relationships among trees in a stand. Superimposing these relationships on a physical map of the stand will show the spatial distribution of each tree's local reproductive success.  This work is in its initial stage, and currently is funded by a grant from the Vermont Genetics Network.

The results of this research could prove foundational for a number of longer-term studies.  Knowing the genetic structure of a population at the level of the individual facilitates studies of gene flow, individual reproductive success, successful dispersal, and succession.  These techniques also invite comparative studies of reproduction among different species and among the same species under different environmental conditions.  

Student Research:

Like all members of the biology department, I place high value on undergraduate research   Research provides students with a deeper understanding of science, and provides important training for those students who pursue a research career.  Since joining the biology department in the fall of 2000, I have advised the following student research projects:

Michael Sipala, 2005.  Genetic and ecological analysis of reproduction in  sugar maple (Acer saccharum)
Kevin Downey, 2002.  An investigation into the field of bioinformatics.
Travis Verret, 2001.  The effect of pre-existing trees on reforestation of Hubbard Park, Montpelier, VT.

Research History:

I studied forest ecology for my doctoral thesis (1981), working at Princeton University with Robert May and Henry Horn.  I examined the dispersal of trees in the eastern deciduous forest that produce spinning samaras:  ash (2 species), maple (4 species), and tuliptree.  My fieldwork focused on documenting the dispersal profile of a number of individual trees of each species by sampling to determine how many samaras landed at given distances from the parent.  I also did photographic analysis and wind tunnel studies to determine the aerodynamic properties of these samaras.  Much of my thesis examined the correlations between dispersal ability, aerodynamic properties, and successional status of these species.  One useful contribution of my work is the concept of wing loading, which allows a samara's terminal velocity (and therefore its potential dispersal distance) to be predicted reasonably easily and accurately from simple morphological measures of weight and size.  This relationship has been corroborated by several other researchers, and has also found its way into exercises in undergraduate courses at several institutions.

The Biology Website is maintained by the Department of Biology at Saint Michael's College.
Questions or comments should be directed to:  Douglas S. Green