Much of the wool spinners and knitters work with has been processed by a fiber mill. These mills will scour, prep, card, and spin wool using machinery capable of processing large batches of wool at a time. Not all mills are alike - local, independent mills have a very different relationship to the fiber they work with than larger commercial mills which are mass producing yarns or fiber. That's not to say one is better than the other, but there are clear advantages to purchasing fiber from a local or independent mill. Wool from independent mills is often directly traceable to the source. Yarns and fibers may come from a single flock or even from a handful of sheep, and there can be some incredible variety in breed content as a result of this sourcing. 

Hand processing, by contrast, does not involve any machinery or milling equipment. Raw fleeces, once shorn from the sheep, are skirted, scoured, picked and prepped by hand. While incredibly time-intensive, this method of prep forms a true connection between sheep and shepherd, processer, and spinner. It also allows for spinners to work with wool from a single sheep, whose fleeces may otherwise be too small for bulk processing at a mill. 

Below is an overview of all that goes into hand processing fleece.

SKIRTING

After being shorn from the sheep, fleeces are skirted. Skirting is the process of removing undesirable parts of the fleece - short cuts, matted, or particularly dirty portions of the fleece - that aren't suited for hand spinning. Often, these skirtings are composted or pelletized, as they make excellent fertilizer for your garden.

Raw fleeces are often described as being lightly skirted, moderately skirted, or heavily skirted. This refers to the extent to which these undesirable portions of wool are removed. A lightly skirted fleece will often have the belly or britch wool removed, along with tags or any heavily soiled portions of the fleece. By comparison, a heavily skirted fleece may have larger portions removed, such as sections with shorter staples, promoting more uniformity within the fleece. 

Fleeces that have been more heavily skirted often command a higher price, as the remaining wool is of a higher quality than the portions removed and additional work is needed in skirting. This may also be a consideration when purchasing fleeces online; lightly skirted fleeces may be sold at a lower price per pound, but shipping costs will be higher than if they'd been more heavily skirted. 

It's important to remember that not all skirted wool is waste wool! For example, neck wool may be removed during skirting, as it tends to trap more vegetable matter (vm) than other parts of the fleece. But neck wool is incredibly soft, and those willing to spend a bit more effort in processing will be rewarded with soft, usable wool. You may see raw wool advertised as skirtings, or seconds - this can often be an accessible, low-cost place to start if you're interested in processing your own fleece. 

SCOURING

Scouring is the process of removing lanolin from the fleece. Lanolin is a greasy, waxy substance secreted by sheep, coating the wool as it grows. Lanolin itself is an incredible substance, capable of waterproofing wool and protecting skin. You may wish to spin "in the grease", without removing lanolin prior to spinning. While offering a unique experience, spinning in the grease can be challenging for even experienced spinners, and many people prefer working with scoured, processed wool. 

The amount of lanolin in a fleece will vary by breed. Typically, fine wools (such as Merino, Rambouillet, or Targhee) have denser, greasier locks and may take more work to scour than their medium wool (Corriedale, Romney, etc.) or longwool (Border Leicester, Wensleydale, etc.) counterparts. This means hotter temps or more rounds of scouring.

It typically takes two or three rounds of scouring to completely remove the lanolin from the fleece. Scouring is done when the water is no longer cloudy. It's important to note that scouring is not intended to remove dirt, or vegetable matter, which will be removed later in the process. It's the cloudiness, not the color, of the scouring water that tells you when you're done. 

PREPPING 

After scouring, fiber is prepped for spinning. Before it can be carded or combed, it needs to be picked open. Picking is the process of loosening the fibers in a lock of wool, allowing it to more easily pass over a carder or through combs. Picking also serves to further clean the fleece, as scouring will remove lanolin and grease but some dirt and vm will remain. As locks are picked open, they release trapped dirt and vm which would otherwise end up on the carder. Larger bits of vm can often be broken into small, difficult to remove pieces when carded, so it's important that as much vm as possible is removed during this stage. 

After picking, fiber can be carded or combed in preparation for spinning. 

Carding can be done with either hand cards or a drum carder. Carding mixes the wool fibers in all directions, trapping air between each fiber and creating a light, lofty prep. When using hand carders, fiber can be rolled off the carders into rolags or pulled off into strips of roving. On a drum carder, fiber is typically lifted off into a batt, or removed using a diz to create roving. Carded prep is often referred to as woolen prep, as it is well suited for woolen or semi-woolen spinning. 

Conversely, combing wools aligns all fibers and creates a smooth, dense prep. Little to no air is trapped between fibers. Combing is typically done using either hand combs or a hackle, each with varying levels of fineness. The resulting fiber is called combed top, and is well suited for worsted spinning. 

Some spinners will choose not to card or comb their fiber, instead spinning directly from the lock. This is a simple method of prep, as spinners only need to pick open the fiber before spinning. This bypasses both combing and carding, and the resulting yarn is largely a product of how the spinner drafts the fiber. This can be a fun way to explore the natural texture of the wool and introduce some variety into prep.