I've done a lot of felted wool applique...on table runners, wall hangings, clothes, etc. There's no difference in it and 'regular' applique....you just don't have to worry about raw edges or turning the edges under. Felt your wool, cut out the design and apply it to your background, whatever that is. I use a blanket stitch around the pieces....sometimes in the color of the piece and sometimes in a contrasting color, depending on how I want it to look.
Here's a jacket I 'decorated' for our daughter, a few years ago...I pinked the edges of some of the appliques on the jacket;

This is the NOv. door hanging I made for her;

the February door hanging; I did some fancy top embroidery where the pieces of the heart met...like a crazy quilt...and, did some around the cuff, too

March door hanging;

Don't use the socalled felt you can buy at places like JoAnns...it's not what you want. What YOU want is real, honest to goodness wool fabric that you have thrown into the washing machine on hot, then the drier, and shrunk the heck out of.....it will then be felted wool, that you can press flat and cut out your shapes from, without worrying about the edges fraying. Go to the goodwill and buy clothes....be sure the tag says at least 80 % wool....you can also dye the fabric a different color, while felting it in the machine. I use a good brand of dye - Cushings Perfection Dyes..phone # on the pkg 1-800-626-7847 Don't use just solid colors.....tweeds, checks, etc, add a lot of interest to your work...all solids make things a bit bland and uninteresting...so, add in textural looking fabrics.

sandra, oh your work is so gorgeous. Thank you for sharing your many tips. I am so excited to try this new art for me.

2 questions:
1. How many times does the wool need to go into the washer and dryer?
2. Can the wool be iron after it is felted?

Thank you!

I have not done this yet but I have been collecting wool from thrift store buys to try my hand at it. I used to have a link to a web site that talked about all the steps and for the life of me I cannot find it now.

This is what I know from memory and you can get books on the subject.

Basically you should be able to "felt" (well, technically, the termis "full" since it's woven) wool by washing it with detergent in hot/cold water and throwing it in the dryer. Basically, the hair follicles on the wool open in the hot water and close in the cold causing it to tangle. I believe the soap and agitation adds to the entanglement of the fibers. It "bunchs up" and become felted/fulled.

Once "felted" it will not ravel so you can cut out your applique shapes w/out having to turn under edges. The fact that you're using a woven fabric makes it stronger than regular felt.

To add to the excitement, you can overdye the wool gorgeous shades with dyes made for wool/animal fibers. (Pro Chem and Cullings are brands I've head of) and the shades seem very rich/intense compared to cotton.

How to know when it's done? Most things I've read say to wash or dye it once but I would snip into it and tug at the edges -- if it ravels, I'd do it again. It's the hot/cold that has a lot to do with it felting so you want to use both hot and cold when washing it. I believe the agitation is important too.

Some wools felt more than others -- the wool in a wool coat and many skirts is thicker and more porous and will felt better where something like a high quality worsted wool or gabardine wool may not felt much because of the tightness of the threads/weave don't let it rub around as much.

Don't try this at home but I know it's true because I wash my good wool business suits in my machine on gentle/cold and hang dry and have never had shrinkage/felting of them. If I cut the fabric apart and then washed and dryed it a bunch I don't know if it would eventually felt or not.

If you go on eBay and search for Felted Wool fabric or Overdyed Wool you can see some examples of what you can do to wool from thrift store clothing with some dye. I plan to make my own for the fun and to save money -- it's pretty pricey stuff to buy, IMO, but GORGEOUS.

Also, Google Wool Penny Rugs to find some beautiful examples of what you can make.

Trudymom....I generally just do it once....I use HOT water, allow it to go through its cycle, and then into the drier..and, ALL wool fabric will felt...even gabardine. It should come out pretty tight, regardless of the weave of the fabric you've used.....obviously, the looser weave the wool, the more shrinkage you'll get...the tighter weave, the less shrinkage, but all will probably felt enough with one wash and dry. When you get it out of the drier, just take a look at it.....you should not be able to pull any threads at the edges....if you can, then do it again. You can iron it, but generally, if you take it out pretty promptly, you won't need to...
Historically speaking this IS 'regular' felt....the way wool was treated to make, for instance, the tricorn hats men worn in the 1700s, that were said to be made from felt ...what is NOW called felt is not felt at all, but a cheaply made imitation that in no way resembles REAL felt...or fulled wool...also called boiled wool.

Fascinating! And seeing Sandra's examples has inspired me to try my hand at this! I have a favorite black blazer at home with a stain on the front. What a fabulous way to save it!
BlueBars

I found this article in my favorites that may interest you -- it's about overdying wool, which also felts it. They are talking about using it for rug hooking, but I would use it for the applique, myself.

I have plans to do this -- have collected wool from thrift stores -- now just need to order the dyes and find the time...

Here is a link that might be useful: Overdying wool to felt and color it