I just wanted to show a few pics on how I make trees. Hopefully someone somewhere will find it helpful.
This one is meant to be an oak [not that I'm fussy about that] I made it quite a while back. It's still alive
I started with a twisted wire frame
Made a second frame very similar to the first and wound them tightly together to make a twin-trunker. They were then covered with DAS modelling clay [from hobby and craft shops] which I always coat with PVA glue as it dries. That stops it cracking:
When all was dry it got a thin coat of greyish brown acrylic paint and I began to glue on the finer branches - coconut fibre from hanging basket liner which I pre-painted:
I like to twist the fibres into clumps and glue them on. Any loops or unruly branches can be snipped out once the glue has set.
Foliage for this was Heki foliage mat, glued on in small pieces. The Heki mat loses a lot of its "leaves" when it's cut or torn. I save them and glue them back on later by dabbing on some PVA then dipping the tree into the loose stuff.
On the layout:
In the next pic there's Woodland Scenics used on the trees either side of this one that has the Heki. I much prefer the Heki, although you could get a similar result by gluing some loose scatter onto the WS foliage.
Here's another that I made. This one is the main tree in the village so I gave it a root system with clay and wire after it was planted:
In this pic the trunk looks a bit thin down low, but clay would fix it.
The tree was extended after planting
This tree is based on a garden twig with other twigs glued into carved recesses to make the major branches. It's roughly 8" high.
I really love making trees. These are on my 00 scale [4mm] British layout. Almost makes me wish my New England layout was not set in winter.