The main contribution of this thesis is a parametric method for generation of single-mesh polygonal tree models that follow natural rules as indicated by da Vinci in his notebooks. Following these rules allow for a relatively simple scheme of connecting branches to parent branches. Proper branch connection is a requirement for gaining the benefits of subdivision. Techniques for proper texture coordinate generation and subdivision are also explored.The result is a tree model generation scheme resulting in single polygonal meshes susceptible to various subdivision methods, with a Catmull-Clark approximation method as the evaluated example.As realistic visualization of tree models is the overall objective, foliage appearance and the impression of a dense branching structure is considered. A shader-based method for accurately faking high branch density at a distance is explored.