  Concerns about biodiversity and the long-term stability of forest ecosystems
have lead to changing attitudes with respect to plantations. These artificial
communities are ubiquitous, yet provide reduced habitat value in comparison to
their naturally established counterparts, key factors being high density,
homogeneous spatial structure, and their even-sized/aged nature.
  Transformation (manipulation of plantations to produce stands more
reminiscent of natural ones) represents a major challenge for forest managers,
and the shift from even- to uneven-aged stand management is far from simple.
Tree species' attributes, too, vary dramatically. This study aims to identify
generic aspects of forest population dynamics, in order to understand the
temporal evolution of single species forest stands from an initial plantation
lattice structure, into an ``old-growth'' state.
  This is achieved using a size-structured model, which implements simple rules
to simulate the growth and fate of individuals in a spatial arena. We
parameterise and discuss model behaviour in the context of available plantation
and semi-natural data from Caledonian Scots Pine stands. We move on to
illustrate the use of the model in predicting the outcome of silviculture, and
discuss results in the context of stand transformation.
