Trees are an inevitable part of a model train layout. We can not think of a model train layout without trees. But it is very important to decorate the trees in a realistic way so that they look natural. Here is a HOW to video with some tips to model your trees in a realistic way. This video teaches how to alter the foliage, change the shape and add detail to armatures. It also shows how to add shadows and highlights to existing foliage and model realistic dead fall.
How to model realistic trees video