Tumble and Scour and....Carbonize? Oh My!
There are times when the search for an answer takes longer than expected, but gives you such a reward in the knowing. I never knew what Vegetable Matter (VM) was. Quite frankly, I never thought about the origins of my roving or yarn at all in my early fiber days. I cared that it was the right color and texture and gave me the result I was after in my project. I picked it up all braided or in pretty skeins ready to work with. Easy peasy!
Then I bought my first cottage-milled roving - so lovely and soft. I was in that smooth rhythmic drafting state when....hold up! What the ...? There were rare little bits of plant matter in my roving - aka VM. It didn’t compromise my work and could be picked out. I was just so used to commercial roving and yarns that it annoyed me. Why is that there? Why couldn’t the mill completely remove that?
So, I searched the internet. I asked questions and accumulated information from my local fiber mill. I read up on the differences between commercial and cottage farm methods on removing plant matter. Now, there’s many that know waaaay more than I do on how to scour and prepare a beautiful fleece. There are awesome books on the subject, plus multiple YouTube videos. If you’re interested, check out this link from Mary Egbert. I’ve also provided some links below if you want to do a deeper dive. However, for our purposes here, we’re only going to concentrate on the differences between small cottage fiber mills and large commercial fiber mills in removing vegetable matter. I’m not an authority in this department, but what I found in my questioning were answers that I hope can help the novice spinner or someone who is new to small cottage milled fibers. There’s a difference in how the two go about removing VM. There’s also a difference in the pathway and end state of the wool and fiber that I believe is important to consider in what you want in your hands, your project and your home. The following questions are mine. They reflect what is important to me. Which methods protect the wool’s integrity and contributes to a sustainable and healthy planet? Which methods honor the character of the fiber, giving it it’s most organic and natural state? You may have different questions and needs, so I hope this comparison helps you in answering some of those.
No matter what animal the fiber comes from (sheep, goat, alpaca, etc.), coated or not, that animal lived in that fleece and attracted some amount of dirt, grime, VM and lanolin (unless they are not a lanolin producing animal, of course.) Here’s where things get interesting....
YOUR LOCAL FIBER MILL:
Local fiber mills receive and process fleeces in small batches. The process of scouring and removing VM can be repeated to get it as clean as possible, depending on how dirty the fleece was when it was received. Many farmers take great care in keeping their animals clean so the mill doesn’t have to work as hard to remove plant matter from the fleeces. The Good Shepherd Fiber Mill in Parker, Colorado describes some steps they take to assure as much VM is removed from each fleece. To begin, skirting (removing undesired matter or fibers by hand) and tumbling (using a tumbler to dislodge loose pieces of vegetable matter) initiates the cleaning process . Then, they wash the fiber with a gentle soap and dry the fibers completely. Picking opens and fluffs the fibers up so more VM falls away and finally, the fiber is carded.
After the entire cleaning process has been completed, an end product is created (roving to spin, yarn to knit, felt, etc.) Any small bits of VM remaining from the cleaning process may still be attached to the fiber. Gentle methods are used the entire time. The end product is a unique and organically processed fiber.
THE COMMERCIAL MILL:
Wool and fiber arrives to the mill the exact same way, same starting point, same issues as the cottage mill, except their quantity is extremely large. Many similar fleeces are processed together in huge quantities and their instrumentation is massive. This can be expected. Their need and demand is great.
When all is skirted, shaken, scoured and carded, the commercial mills still have a VM issue. However, repeating the cleaning process and picking out plant matter to have perfect roving or yarn is unrealistic, so the commercial mills turn to chemicals.
They put the fiber through a process called carbonising. According to the Woolmark Company, “carbonising is a continuous process which combines scouring to remove the wool grease and a chemical process which removes vegetable matter such as seeds, burs and grass.” If the percentage of VM is 2-3% or higher, the wool is soaked in a solution of Sulphuric Acid (H2SO4) and then baked at 95-120 degrees Celsius (203-248 degrees Fahrenheit.) These temps turn the plant matter in to dust. Once the baked VM is crushed and shaken off, the wool has to be neutralized from it’s acidic state. It’s passed through an alkali solution of Sodium Carbonate (Na2Co4) and then a final bath of Hydrogen Peroxide bleach (H2O2) to brighten the color before drying. Sometimes, it’s chlorinated or subjected to additional harsh chemicals.
Comparatively, there’s much more manipulation to the wool’s natural state. What started out as fiber with sustainable qualities becomes a toxin laden wool completely void of unique and proud personality. On the upside, the quantity they can turn out without a speck of VM is amazing!
Through the years, I have become more and more familiar with processing and preparing fleeces for spinning or felting. As the fiber is properly prepared, the quality and unique characteristics of these fibers shine! Yes, vegetable matter may be a minor annoyance, but the organically processed strands of wool and fiber are more beautiful and more true to the breed from which they grew than anything I’ve been able to buy from a commercial source. It’s a living testament to the animal - not generic or unrecognizable. Local grown and processed fiber is a choice I’ve never regretted and is now my main source of roving and yarn.
Those questions took me on a little trip that offered me not only beautiful shiny shades of fiber and a fabulous end product, but an investment in small farms, my community and the wonderful animals that grow beautiful fiber year after year. When you see small bits of vegetable matter show up while you spin or knit, I hope you smile and thank a local mill for keeping your wool real.
Sources:
Mary Egbert , “Camaj Fiber Art's Complete Scouring and Fiber Prep Guide: The Art of Washing Wool, Mohair and Alpaca - Scour Wool Like a Boss”
https://camajfiberarts.com/collections/how-to-scour-wool-mohair-alpaca
https://www.youtube.com/user/camajhandspunyarns
The Good Shepherd Fiber Mill, “Terms to Understand,” Accessed August 2, 2020, http://thegoodshepherdfibermill.com/description-of-terms.html
The Woolmark Company, “Scouring and Carbonising,” Accessed August 31, 2020, https://www.woolmark.com/industry/use-wool/wool-processing/woollen-scouring-carbonising/