This is also the part that provides the most problems for budget modelers, since the products out there for modeling foliage tend to be pricy, and to make your own tends to require special equipment (like a blender) and materials that are tricky to find (like cushion foam.) Foliage also presents problems in terms of durability, since delicately made trees will not stand up well to transportation, and will often scatter material all over the place if handled roughly.
I won't pretend that I've solved all of these problems. But my method does produce a tree that looks awesome, is reasonably sturdy (I mean, don't go, like, throwing it or anything...) and is extremely inexpensive. That way, even if somebody does grab it around the trunk and shake it vigorously until it falls apart, at least it didn't cost you 25 bucks to make.
Here's What You Need:
Polyfiber (Less than $5 at a Joan Fabrics or Michael's, and enough for 5-10 *ucking FORESTS. I got lucky when my boss gave me some for free. He gave me less than a quarter of his giant bag-- a whole shopping bag full!)
Black Acryllic Paint
PVA Glue
An old paintbrush
Cheapo Hairspray (Mine was $1.25, cheapest on the shelf, works great)
Magic Wash in a pump action spray bottle (A.K.A. 1 part Pledge Floor Polish With Future Shine: 4 parts water). The Spray Bottle will cost you around 3 or 4 dollars, but it's worth it, since spraying magic wash on things is a simple yet durable clear coat. Plus, you can put acrylic paint diluted with isopropyl alcohol in there and you have a poor man's non-toxic spray paint-- great for terrain, especially for large areas of sand which soak up paint and destroy brushes. Also, it is illegal to sell spray paint in Chicago, so...
Newspaper, or other surface on which you can smear paint
Some colored flock or ground foam. The tea-leaf flock I made is designed specifically for this purpose, and is super-cheap to make.
What to do with all this crap:
Step 1: Preparing the Polyfiber
First off, pull of a small lump of polyfiber, maybe about twice the size of a ping-pong ball.
Got that? Good. Now here's a picture of what you're not going to do:
DO NOT just go sticking on giant clumps of polyfiber in the hopes of making a gloriously verdant tree. And for the love of god do not continue to do so as pictured below:
This was my first experiment in foliage making, and it turned out horribly. Pictured is just the dry-fitting stage (not necessary in the correct procedure I outline here). I had to then try and color these giant puffballs all the way through--which proved impossible; then I had to try and glue them to the tree in a secure way-- which also proved impossible; and finally I had to try and adhere the foliage to the puffs without weighing them down so much that they would fall off-- which proved the most impossible. I eventually had to cut these guys off, leaving a residue of white fuzz covering the branches and nearly ruining my tree.
INSTEAD what you want to do is take that little lump of polyfiber and tease it into a thin sheet. I actually divided my lump into three and made three different sheets, as it made coloring them easier.
Once that's done, put a squidge of black paint on your newspaper. add a squirt of water or Isopropyl alcohol to thin it a little. Then take one of your poly-sheets and smear it around in the paint. You're trying to get it entirely coated in pigment, while avoiding clumps where possible. Repeat until all of your sheets are colored. Note that this is messy, and if you don't like having paint on your hands, you should wear gloves. Also note that you may have to rearrange your fiber into sheet form, as the smearing process can cause them to ball up.
Set these aside to dry. Maybe make some flock while you're waiting.
Polyfiber sheets drying.
Step 2: Dressing the Tree
Once your fiber is dry, use a pair of scissors to cut out a 1-2 inch square section. Tease this tiny portion of fiber out as much as you can without causing it to fall apart. I am talking SUPER wispy. The wispier the fiber, the more convincing it will be as small branches.
Take your junk paint brush and apply some PVA glue to the first branch you want to dress. Make sure to apply it all around the branch, but in a thin coat that won't drip on your base.
Carefully place your teased-out polyfiber onto/around the branch. It won't take much to get it to hold, but just in case I like to give the fiber a quick pinch into the glue. You can also wait about 5 minutes for the glue to get tacky before applying the fiber. Both work.
Repeat these steps until your entire tree is satisfactorily covered in fiber. I cannot emphasize enough that less is more here. It looks more realistic to have small bunches of twigs around the branches than huge masses, and it makes the flocking process much smoother.
Step 3: Adding the flock
Once the glue is dry, gather your flock and your hairspray.
Autumnal red, my favorite.
Now, turn your tree upside down by the base. Spray the under-side of your polyfiber branches liberally with hairspray. I'm talking enough to cause the sprat to bead slightly. Then, making sure to hold the tree over some kind of container, sprinkle your flock generously over the fiber. Gently shake off excess.
Turn the tree over and repeat the process with the tops of the branches. Between each layer, make sure to brush off any leaves that are sticking to the trunk with a soft paint brush. Be careful not to touch the trunk with your fingers as the hairspray will stick to them and they will pull the paint right off.
Work gradually. Rather than risk a surplus of flock at one time, allow a layer to dry before adding more. This will let you build up a good volume of foliage without deforming the polyfiber too much. Here too, less is more. Actual trees are not solid masses of leaves, but have lots of empty space. Make sure to leave some fiber exposed as it will add to this impression.
You may notice that some of your foliage flock has stuck to the base due to overspray from the hairspray. Allright! Automatic natural leaf-scatter!
Now for the most crucial step in making your tree as sturdy as possible. Fill your spray-bottle with magic wash, set it on the finest mist setting it can manage, and give your tree a good spray down, all over. This will help fix down your foliage as well as seal and protect your paint and your basing material. When that dries, spray it again. And when that dries, spray it one more time. Continue doing this until no noticeable foliage falls from the tree when you shake it gently. And then spray it again.
This will make the tree slightly shiny. I don't mind this since I coat all of my figures and terrain in magic wash, since it's one of the most durable clear-coats available. However, some people don't like the shine. If your one of those, just go over the top with testor's dull-cote. I hear that does the trick.
Once it's sealed and dry, it might be a good idea to go back with a pair of scissors and trip any wayward wisps. I haven't yet, since I'm still basking in the glow of my tree, but these things can detract from the realism (see last picture. Case in point.)
And that's it. Not so bad, right? And crazy good looking, too. I have yet to see the commercial product to rival it. Here are some pics of the finished product with my color test Bloodbowl orcs for scale reference:
----"Blimey... wot's dis prufoud feelin' uv peece warshin' over me?" ----"...'Arvy? Oi fink its dis tree.... dis byoooootiful tree..."
I swear one of these days I'll make a backdrop.
Sites that were helpful/inspiring in designing this tutorial:
http://pmrr.org/Articles/Scenery/ GenericForegroundTrees.htm
http://www.trainboard.com/grapevine/showthread.php? 96067-Making-Poly-Fiber-Trees- Quickly-Part-1
http://jehubbard.com/hobbies/tree_tips.htm