Ouessant Wool 101

     N° 1 : "Introduction"

I admit it. I love wool. It’s true that I have a bit of a preference for Ouessant wool. But, it must be said that I love wool in all its many forms : from the unbelievable fineness of a Merino to the beautiful luster of a Lincoln Longwool. And let’s not forget Shetlands and Corriedales. Yes, I love them all!


That being said, my passion for wool is not without reason. Wool is a noble fiber whose textile properties have been appreciated for more than 12,000 years. For example, among its many qualities :
  • Wool is insulating. It insulates against the cold as well as heat, thanks to the quantity of air that is trapped in its fibers. Wool keeps us warm during the winter and is pleasant to wear during the summer.
  • Wool is an excellent regulator of humidity : it can absorb up to 30% of its weight in humidity without feeling damp. This hydrophilic property of wool allows it to breathe.
  • Wool has excellent elasticity and memory. Thanks to these properties, garments made from wool keep their shape and resist wrinkling.
  • Wool has a natural affinity for dye : it is a textile fiber that is easy to dye.
  • Wool is naturally fire retardant.
  • Wool is an all-purpose textile fiber. Wool is available in a variety of forms because every breed of sheep produces a particular type of wool that is characteristic of that breed. As a result we can find a wool to make a layette for a new born baby, a wool to make rugs, and yet another wool to make sweaters and hats.
  • Additionally, wool is a natural resource : renewable and ecological.
The special properties of sheep’s wool ensures it a place of honor among textile fibers.

But what exactly is sheep’s wool?

As John Bernard D’Arcy* has explained in Sheep Management and Wool Technology, “ In general, the fibers forming the covering or fleece of sheep are similar to those of other hairy-coated mammals. (...) In a general sense they are all hair fibers, but those grown by the sheep are referred to as ‘wool’.”

Like hair fibers from the coats of all mammals, wool is produced from keratin and is made up of two and sometimes three distinct parts : the cuticle, the cortex, and sometime (but not always) the medulla.


Cross Section of a Wool Fiber
(After Fournier & Fournier, 1995 ) **

The cuticle or outer layer of the fiber is made up of scales. The scales, or rather the size of the scales, determine the luster of the fiber : as the size of the scales decrease and the number of scales increase, the luster of the wool decreases. Essentially, the size and number of the scales determine the reflective properties of the wool. For example, merino, which is known for its fineness, is a relatively mat wool : merino wool has over 2,000 scales per inch . On the other hand, the wool from a Lincoln Longwool, a breed that is know for its luster, only has 700 scales per inch.§

The cortex takes up approximately 90% of the volume of each fiber. The cortical cells are in the form of long tubes : every cortical cell contains macrofibrils, which contain microfibrils, which contain alpha-helical protein chains. This complex structure, which can make one think of a set of nested boxes, gives wool its strength and elasticity.

From time to time, albeit rarely, wool can also have a medulla. The medulla is the result of incomplete keratinization which produces a more or less continuous hollow canal in the middle of the fiber. A fiber with a medulla is called a medullated fiber. It is often said that wool is not medullated and that hair is. This is not always the case. Wool can be medullated and quite often hair is not medullated. At the same time, it is often said that only coarse fibers are medullated. This statement is also not true. So, be careful about received wisdom! That being said, we should keep in mind that the presence of a medulla produces a fiber that is stiff and brittle.

* D'Arcy, J. B. Sheep Management and Wool Technology. Kensington : New South Wales University Press, 1981. (p.69)
§ Parkes, Clara. The Knitter’s Book of Wool. New York : Potter Craft, 2009. (p.13)

** Fournier, Nola, and Jane Fournier. In Sheep's Clothing : A Handspinner's Guide to Wool. Loveland, CO : Interweave Press, 1995. (p.15)

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N° 2 : "Primary & Secondary Fibers"

Like hair fibers from all mammals, every fiber in a sheep’s fleece comes from a follicle. But it’s important to keep in mind that there are two different types of fiber producing follicles on a sheep : primary follicles and secondary follicles. The fibers produced by these two types of follicles are know as primary fibers and secondary fibers.

The primary follicles develop between the 35th and 40th day of gestation : in other words, quite early in the life of the fetus. As for the secondary follicles, they don’t develop until the end of the gestation period and sometimes after birth.

You can tell these two types of follicles apart not only by when they develop, but also by the types of fibers that they produce. Primary follicles that produce primary fibers, are grouped into clusters of three. The primary follicles are bigger than secondary follicles, which means that the primary fibers are thicker than the secondary fibers. The secondary follicles, which are smaller and produce finer fiber, cluster around individual primary follicles.

The ratio between the number of secondary fibers to the number of primary fibers varies quite a bit between different breeds of sheep : between 3 to 50 secondary fibers for 1 primary fiber. For example, in merino sheep, the ratio is very high, with 50 secondary fibers to every primary fiber. Whereas this ratio is much lower with primitive breeds of sheep.

In order to appreciate the fundamental role played by primary and secondary follicles in the construction of an Ouessant fleece, it’s very important to understand the evolution of sheep’s wool during domestication.

In his study on this very subject, A. R. Bray* traces the evolution of sheep’s wool starting with the wild mouflon sheep, the ancestor of modern domesticated sheep. As Bray has said, the wild mouflon has a double coat with a very soft down coat made up of extremely fine crimped hairs that grow from the secondary follicles. These fine fibers (quite a bit finer than merino wool) are clusters around the long, thick, medullated hair fibers the grow from the primary follicles.

(After Bray, 2004) *
During the evolution of sheep’s fleece, a number of changes take place.

First, all of the types of fibers in the fleece grow more : both longer in length and over a greater period of time. When looking at the coat of the wild mouflon, we notice that the fibers grow for a few months, then they stop growing during the winter months. In the spring, the animal molts, and then the cycle starts again. But at this stage in development all of the fibers in the sheep’s fleece grows without stopping and normally the sheep no longer sheds its fleece.

At the same time there is an evolution in the follicles : the primary follicles become smaller while the secondary fibers become bigger. There is still a definite difference between the two, but it’s not as marked as it is with the mouflon. This change in the size of the follicles influences the size of the fibers produced by the respective follicles : the primary follicles produce a couple of different types of garde hair, including a fiber called a heterotype ; on the other hand, the secondary fibers produce a fine wool. It must be stressed that this type of fleece is not at all uniform : it contains a number of different types of fibers with differing diameters. This intermediate stage in the evolution of sheep’s wool corresponds with the fleece of primitive breeds of sheep.

(After Bray, 2004) *
Finally, if we look at a modern sheep like the merino that has been “improved” and selected to produce a very fine and uniform fleece, we will see yet again another evolutionary change of the sheep’s follicles. At this point, the primary follicles and the secondary follicles are the same size and both produce a very uniform wool. At the same time, the ratio between primary and secondary follicles changes : there’s an increased number of secondary follicles for each primary follicle.


(After Bray, 2004) *
And so where does all this leave our little Ouessant sheep?

'TitBijou with her amazing primitive fleece.
The Ouessant sheep is neither a wild mouflon or a merino : the Ouessant sheep is a little rustic sheep with a beautiful primitive fleece.

* Bray, A. R. “Fleece Types Developed During Domestication.” In The World of Coloured Sheep, The Proceedings of the 6th World Congress on Coloured Sheep, Christchurch, New Zealand, November 2004, edited by Roger S. Lundie and Elspeth J. Wilkinson, 34-37. New Zealand : The Black and Coloured Sheep Breeders’ Association of New Zealand, 2004.
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N° 3 : " The 4 Fiber Types Found in an Ouessant Fleece "


As a primitive sheep, the Ouessant produces a fleece that is quite distinctive : the primary fibers form a type of outer coat and the secondary fibers make up the inner coat of wool.

As I have already said in a previous article, the primary follicles produce several different types of fiber and the secondary follicles produce relatively fine wool.

But what exactly are these different types of fiber that we can find in an Ouessant fleece?

In general, we can identify 3 different types of fiber in an Ouessant fleece. Let’s look at the fleece of Dagobert, a castrated grey Ouessant ram.

His fleece is altogether typical of an Ouessant fleece. Please note that I have chosen to look at grey Ouessant wool because it is easier to see the different types of fiber when looking at this type of fleece. That being said, we see that exact same thing in a white or black Ouessant fleece ; but it’s more difficult to show with the camera.

In the following photo, I’ve tried to dissect a lock of Dagobert’s grey wool to show you the different types of fiber that can be found in an Ouessant fleece.


Please click on the photo to enlarge.

On the left we see a lovely lock of wool, exactly as it grows on the sheep.
On the right, we see the 3 types of fibers that are found in the lock of wool.

As we have already seen, the two different types of hair follicles on a sheep produce different types of fiber. In Ouessant sheep, guard hairs come from the primary follicles and wool comes from the secondary follicles.

The guard hairs come in two distinct forms : heterotype fiber and hair fiber. These two types of fiber both come from primary follicles and as a result the diameter of these fibers is greater than that of the secondary fiber (wool). At the same time, these two types of guard hairs are quite a bit longer than the wool fibers, which creates a lock of Ouessant wool that has a tapered or feathered tip.

To begin with, we see the long guard hairs in the fleece. These hairs, not as numerous as the heterotypes, are supple and relatively fine. The scales on these guard hairs are smooth and flat, which results in a fiber that has a certain amount of luster. The number of guard hairs varies quite a bit from animal to animal, keeping in mind that rams generally have more hair than ewes. Additionally, hair fibers tend to be found in specific parts of the fleece. For example, there are more hair fibers along the backbone, on the front of the chest, and on the sides. These hairs, which are longer and often darker than the wool can give the sheep a rather shaggy look. Marcus, a young ram born in 2010 is a good example of this.

Marcus, black ouessant ram born 2010, grey and brown carrier

Nevertheless, there are more heterotype fibers than hair fibers. Like the hair fiber, the heterotypes are also longer than the wool. The heterotypes are, as their name suggests, a hybrid type of fiber : the tip of the fiber looks like a hair fiber while the end that is closest to the sheep resembles a wool fiber.

Heterotype fibers in Jasper's fleece

It is often said that heterotype fibers as well as guard hairs, are medullated fibers. This is not true. I have had a number of laboratory tests done to determine the percentage of medullated fiber in an ouessant fleece. To be honest, I was quite surprised by the results : on average there was only 0.8 % medullated fiber in these fleeces (4 tested), which is quite low. So remember to always be wary of received wisdom!

Of course, now that I think about it, it makes a lot of sense. Knowing that medullated fibers are usually very stiff, brittle, and straight, if an Ouessant fleece contained lots of medullated fiber, the hand of the spinner would have felt them. But what this spinner has felt in an Ouessant fleece is the polar opposite of medullated fiber : I have discovered a relatively fine wool mixed with lustrous, supple fibers that look and feel oddly like mohair, a hair type fiber that is not medullated! In the following photo we can see just how much ouessant wool looks like a mixture of wool and mohair.

Please click on the photo to enlarge.

These two types of guard hair – heterotypes and hair – make up the outer coat of the fleece which protects the wool fibers. Ouessant wool fibers are generally quite fine and grow from the secondary follicles. This wool has prominent scales covering each fiber which causes Ouessant wool to be rather matt.

Normally, we only find these 3 types of fiber in an Ouessant fleece : wool, heterotypes, and hair. Nonetheless, please be warned that there is a 4th type of fiber that sometimes can be found in an Ouessant fleece. Fortunately, this 4th type of fiber is quite rare in Ouessant wool : after having worked with over 100 different Ouessant fleeces, I have only ever found this type of fiber in one ewe’s fleece ; also, from time to time (but again very rarely) one can find this type of fiber in small quantities on the back legs of some rams.

So then, what is this infamous fiber ? It’s kemp.

Kemp is the vestige of the mouflon, distant ancestor of the Ouessant sheep. Kemp fibers are medullated : thick, short, brittle, stiff, and rigid. Kemp is produced by the primary follicles and they have a very short period of growth, after which they molt and mix into the wool fiber.

Kemp is not at all appreciated by spinners. Without a doubt, this is one of the reasons why kemp is so seldom seen in Ouessant Sheep or for that matter in other breeds of sheep.

That being said, from time to time ... they are seen in an Ouessant fleece.
Much to my horror (yes, horror!), that’s exactly what I found when I sheared Chloé.


Please click on the photo to enlarge.

In the following photo, we can see the kemp or short hairs (that look like goat hair) that have not yet fallen out from around Chloé's neck where the wool has started to molt.


Please click on the photo to enlarge.

This was the first time that I removed a sheep from my flock due to an incorrect fleece.

Fortunately, kemp is rarely found in an Ouessant fleece. Nonetheless, in my opinion, the presence of kemp is a serious fault in a fleece, and a conscientious breeder should not use such animals for breeding.

Yes, as we have seen, the Ouessant sheep produces a fleece that is quite distinctive . And as for me I proclaim the beauty and the distinctive character of Ouessant wool.

What a joy and privilege to be able to work with such amazing wool.
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n̊ 4 : "Uniformity"

As we have already seen, an ouessant fleece is quite distinctive : it consists of several different types of fiber of varying lengths and of varying fineness. The variation that is found in an ouessant fleece is the exact opposite of the uniformity that is so sought after by the textile industry.


Brown and White Merino Fleece
The Merino, an improved breed of sheep, is known for its fine uniform fleece.

In all of the so called modern or improved breeds of sheep, uniformity has been one of the most important criteria of selection. Yet, our little ouessant sheep have never been improved. The ouessant sheep has a primitive fleece that exhibits a lack of uniformity on a number of different levels. Most notably, it has fibers of various length. It also has fibers of varying fineness. And let’s not forget the general lack of uniformity over the fleece as a whole.

The lack of uniformity in fiber length is particularly striking in an Ouessant fleece. The variable fibre length of an Ouessant fleece results in the typical tapered tips of the locks. This same thing is seen in the fleeces of other primitive sheep. For example, in the following photo there is a lock of Ouessant wool with a lock of Icelandic wool on the left and a lock of Shetland wool on the right. Icelandic and Shetlands are both primitive sheep and are considered to be “cousins” of Ouessant sheep because all three of these breeds are members of the Northern European Short-Tailed group of sheep.


Please click on the photo to enlarge.

The tapered tips of an Ouessant fleece are the result of different types of fiber that have differing lengths. On the other hand, in a fleece from an improved or modern breed of sheep, the shape of the lock is rectangular and does not have tapering tips. These “square”, blunt tips tell us that the fleece has only one type of fibre in the lock. For example, in the following photo, there is a lock of Ouessant wool and 3 locks of wool from modern, improved breeds of sheep.

Please click on the photo to enlarge.

As we have already seen, an Ouessant fleece contains several different types of fiber, each having various fiber diameters. Sometimes the various fiber diameters are easy to see with the naked eye, but often they are hard to see.

On the other had, in a fleece from an improved breed, the diameter of the wool varies very little : the wool can be very fine, like a Merino ; or stronger and more robust, like a Romney. In either case, the fiber diameter is homogeneous.

Yet, when we look at an Ouessant fleece, we will find a mix of fibers, some being very fine and others being more robust. For example, I had some of Dagobert’s fleece tested in a laboratory. Essentially, his fleece consists of fibers that are as fine as merino wool and fibres that are as robust as Romney wool.

Please click on the photo to enlarge.

We can also talk about the uniformity of the fleece in general. In other words : wool from the neck will look just like wool from the side which will look just like the wool from the britch or back legs.

This is exactly what we see in improved breeds of sheep : these sheep have been breed to produce a very uniform fleece so that the wool over the whole body of the sheep will be of the same quality.

The Ouessant is a primitive breed of sheep, and as such there is a lot of variation in an Ouessant fleece, it is anything but uniform.

For example, this year I used two rams for breeding : Chit (des Lutins du Montana)

... and Caramel...

These two rams are from different lines and each one has his own particular look : Chti’s fleece is quite a bit shorter than Caramel’s ; additionally, Caramel’s fleece seems to be a lot more primitive than Chti’s. But careful! Don’t jump to any conclusions. Appearances can be deceptive! It is true the Chti’s fleece is on the whole finer and shorter than Caramel’s. That being said, we see the same thing happening in both of these fleeces.

I took three fleece samples from each of these rams : one from the neck (excluding the mane), one from the side, and one from the thigh.

Here are the samples taken from Caramel’s fleece :

Please click on the photo to enlarge.

The difference between the three samples is quite striking ! It speaks volumes ! Nonetheless, I would like to add just one comment : the wool is quite a bit finer around the neck and coarser around the thigh, without taking into account the heterotypes and the gard hair.

As for Chti :

Please click on the photo to enlarge.

We actually see the same thing happening in Chti’s fleece that we saw in Caramel’s fleece.
  • The sample taken from around the neck (excluding the mane) is shorter than the other samples and is in the form of a rectangle. What this means is that there is very little variation in the types of fibers in this sample. The wool is also very fine and soft.
  • The sample taken from the side is longer than the one taken from around the neck and it has tapered tips. What this means is that there are a couple of different types of fiber in this lock of wool : in this instance, there is wool (that is the same length as the neck wool) along with quite a number of heterotypes.
  • The sample taken from the thigh is even more outstanding than the side sample, with its length, tapering tips and multiple fiber types. Again, the wool is essentially the same length as that found on the side, but not as fine.

It’s true that uniformity is not to be found in an Ouessant fleece ...


Mira, Praline & Chti

... but incredible beauty ... that you will find !

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n̊ 5 : "Of Locks, Style, and Character"

Sheep’s wool naturally grows in the form of locks. A lock of wool has a very distinctive look and to a certain extent it is the lock formation that makes for a beautiful fleece.

In general, when wool is growing on the sheep, the individual fibers tend to organize themselves into small clusters of wool. These clusters or locks of wool can be seen when you spread open the fleece of a sheep. They can also be seen after shearing, when the fleece seems to naturally break apart into small clumps or clusters of fibers.


Please click on the photo to enlarge.

In particular, Merino wool is noted for its very distinctive, beautiful locks. But all of the so-called modern and improved breeds of sheep also have their own characteristic lock structure.

Please click on the photo to enlarge.

Unlike the improved breeds of modern sheep, the Ouessant sheep and his primitive cousins don’t have a distinctive lock structure.

Please click on the photo to enlarge.

Primitive sheep lack distinctive, well formed-locks, which makes the fleece look like a solid mass of wool. The Ouessant fleece is no exception to this rule. Jasper’s fleece is an excellent example of this lack of lock structure :

Please click on the photo to enlarge.
In order to separate a “lock” of ouessant wool from the fleece, you need to pull the lock out of the fleece by its long tapered tips. Even then, although the lock of wool is separated from the fleece, we can see that a lock of Ouessant wool lacks structure.

Please click on the photo to enlarge.

So what exactly is this structure? And why does the merino have so much of it and our little Ouessant sheep so little and so rarely?


Lock structure is dependant on one thing : uniformity! For a beautiful, well structured lock, all of the fibers must line up perfectly. And in order to do this all of the fibers must be very uniform. When there are several different types of fibers of varying lengths and diameters the fibers cannot line up with each other. Additionally, the presence of these different types of fiber makes it almost impossible to see the wool’s crimp.

As we have already seen, uniformity is not one of the qualities of an Ouessant fleece. So the lack of well structured locks of wool in an Ouessant fleece should not be at all surprising.

That being said, from time to time we do find locks of Ouessant wool that almost have a distinctive structure. But this is relatively rare and generally only found in certain areas of the fleece, notably around the neck. For example, in the following photo, we can see a few more or less distinctive locks of wool around the neck of Chti des Lutins du Montana.


Please click on the photo to enlarge.


In the world of textiles, when we see well structured locks of wool that have a distinctive crimp pattern, we talk about a fleece that has style. On the other hand, we talk about a fleece’s “character” when we want to describe the overall look of a fleece : the style of the locks, the crimp pattern, and the color & feel of the wool.

So even if an Ouessant fleece doesn’t have a lot a style, in my opinion, it does have a distinctive character : both soft and rustic, in a range of exquisite colors ...
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n̊ 6 : "The Beauty of Crimp"

As we have already seen, a fleece with well structured locks and a distinct crimp pattern has style. But what exactly is this wavey crimp that we can see in a lock of wool?

Merino wool, renowned for its fine even crimp pattern
Please click on the photo to enlarge


Crimp is the term used to describe the waves or curls found in the lock of wool ; and to a large extent, crimp influences the overall look of a fleece. At the same time, the most valued qualities of wool are directly links to crimp. It’s thanks to crimp that wool is

• insulating,
• light,
• airy,
• and elastic.

Generally speaking, fine wool has more crimp than coarser wool. For example, fine wool can have between 14 to 30 crimps per inch ; a medium grade wool will have between 8 to 14 ; and for coarser wools, the number of crimps per inch can vary from 1 to 8.

The waves in the crimp pattern are the result of two types of cells that are at the same time similar and antagonistic : the orthocortex and the paracortex.

(After Fournier & Fournier, 1995) *
The orthocortex is found on the “outside” of the curve while the paracortex is found on the inside.


When there are more orthocortex cells than paracortex cells, the wool has less crimp. On the other hand, when there are more paracortex cells than orthocortex cells, the wool has more crimp.

The look of crimp does vary quite a bit among the different breeds of sheep. Each breed of sheep has a particular style of crimp : from the fine even crimp of the merino to the big, open curls of the gotland.

Please click on the photo to enlarge.

And what about the Ouessant sheep ?
As we have already seen, The lack of uniformity in an ouessant fleece tends to hide the crimp. If a fleece is uniform, whether it’s a fine fleece like the merino or a medium fleece like the romney, the crimp pattern is quite distinct and easy to see. However, this is rarely the case in an Ouessant fleece. The following photo is an excellent example of this phenomenon.

Please click on the photo to enlarge.

Nonetheless, from time to time we can see crimp in an Ouessant fleece. Normally, we will only see crimp around the neck, where the fleece is more uniform. In the following photo, we can see 4 locks of Ouessant wool, all with a fine crimp pattern. Please note that it is more difficult to see in Caramel and Isard’s wool, even if it is easy to see with the naked eye. (It must be said that it is rather difficult to photograph crimp!)

Please click on the photo to enlarge.

Still more crimp, again from around the neck. This time from a white Ouessant ewe.


Please click on the photo to enlarge.

... and from Chti, black Ouessant ram.


Please click on the photo to enlarge.

But be careful! Even if we can’t see any crimp, it doesn’t necessarily mean that there isn’t any!

First, a little warning ! Crimp is quite variable in an Ouessant fleece : some sheep have more than others. But when an Ouessant fleece does have crimp, it is usually hidden in the heterogenous locks. For example, let’s look at this lock of wool from ‘TitBijou :

Please click on the photo to enlarge.

Basically, one would say the there isn’t any crimp in this lock. Yet, if we separate the long guard hairs from the wool, we find a very fine wool (average fiber diameter of 18 microns) that has crimp! These beautiful fibers are both very soft and elastic.

Please click on the photo to enlarge.

Of course, some Ouessant sheep have very little crimp. Nonetheless, generally speaking, there is crimp in an Ouessant fleece, even if it is difficult to see.

* Fournier, Nola, and Jane Fournier. In Sheep's Clothing : A Handspinner's Guide to Wool. Loveland, CO : Interweave Press, 1995. (p.15)

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