FLEECE CHARACTERISTICS

CHARACTERISTICS OF SHETLAND FLEECE
A BREEDER’S PERSPECTIVE©
By Linda Wendelboe
(Click for a Printable Version Click for In Depth Fineness)

From the early times of the Shetland islands, from the pre Viking era to the present, the sheep of these islands have changed to meet the needs of their shepherds. Additions of new sheep to the genetic pool1, selection pressure by the environment and selection by the shepherds in response to changing situations have impacted the fleece characteristics of what is now known as the Shetland sheep. The result is a significant amount of diversity in the fleece characteristics that show up in the offspring of the registered Shetland sheep population.

The Breed Standard used by the North American Shetland Sheepbreeders Association (NASSA) was written by the Shetland Flock Book Society of the Shetland Islands in 1927 with the aim of preserving the classic Shetland, preventing loss of type through crossbreeding or indiscriminate breeding. The Shetland Sheep Society (dealing with the United Kingdom outside of Shetland) also uses this standard and NASSA's predecessor adopted a similar standard for use in North American in 1991. NASSA reaffirmed the 1927 Shetland Flock Book Society Standard in 2000. Breeders should review the Breed Standard requirements for fleece characteristics when making decisions on breeding and registration of their sheep.

The following excerpts are from the Breed Standard. The classic Shetland that meets the Breed Standard has:

"Wool- Extra fine and soft texture, longish, wavy, and well closed.
Wool on forehead and poll tapering into neck, likewise wool on cheeks. "

DISQUALIFICATIONS
(b) Bad wool, coarse and open
(c) Very coarse wool on breeches

This description does not have specific ranges or measurements so must be interpreted within the context of wool production. Each characteristic will be discussed in turn.

Extra Fine: A survey of wool production material and handspinners literature2 shows a range for Shetland wool from approx. 20 to 30 microns. This is roughly equal to a range of 54 – 66 in Bradford Count. There is Shetland wool that is much coarser than this, but it would not qualify as being in the extra fine range. Keep in mind that coarse, open wool is one of the listed disqualifications. In the American Wool Council Glossary, wool over 31 microns is considered to be coarse3. See FINENESS for more information on this characteristic.

The requirement of extra fine has to be applied to the whole sheep, not just the neck or the shoulder where the best wool may be found. A typical Shetland fleece does show some variation in fineness from neck to britch. How much variation is important as another one of the registration disqualifications is for "very coarse wool on the breeches".

As a general guideline, if the wool at the midside on the sheep is within the range of extra fine and the britch area is not too much over the coarse end of the range and is not too large, it probably meets the requirements.

Soft Texture: This requirement most closely corresponds to the hand or handle of the fleece and is a subjective measure. It is influenced both by the genetics for fleece found within the sheep as well as external factors such as health, diet, climate, stress levels, etc. Dry, very sunny conditions will sun bleach the tips of the fleece and give the tips a rougher feel than the inside of the fleece. Mineral imbalances such as copper deficiency or molybdenum toxicity will create quite a harsh hand, even though the fleece may be fine in diameter. Some fleece feels chalky, some fleece feels smooth, some fleece feels crisp; all of these types of sensations will have an impact on the overall assessment of softness.

The resistance to compression of the fibres will also play a part here. A fibre that "pushes back" strongly when compressed (highly resistant to compression) will not feel as soft as a fibre that does not "push back" as strongly. Much wool that is coarser than 28 microns has been found to be highly resistant to compression and have a harsher handle4. This is a different concept from that of compressing a handful of fleece to gauge density (see below: "Well Closed").

Fineness and degree of uniformity will also have some impact on how soft a fleece will feel. Coarser fleeces and fleece with highly variable fibre diameters tend to feel less soft5. See also Uniform and Single Coated Fleece.

All in all, it is difficult to set a rule for how soft is soft enough. Some people are able to distinguish tactile differences better than others. Handling a large number of Shetland fleeces from different breeders (at a fleece show for instance) can give an idea of the range to be found. One way to start the process is to identify the harsh hand, the over dry hand, the fleece that causes quite a bit of prickle against the skin and take these out of the picture as not having a soft enough texture. Identify the fleece that feels "special" and use it as a target. Another method is to establish simple reference points. Cashmere is generally very soft. Horse hair is quite "hard". Shetland fleece should be closer to the cashmere end of the range.

Longish: This characteristic is subject to a variety of interpretations in different parts of the world6.

To set up some wool context: a staple of 2 - 3 inches is generally considered on the short side in the wool world. Examples: Down type breeds have short wool, generally 2 - 3.5 inches long; Suffolk is described as having a short, down type fleece with staples of 2 – 3 inches7. Longwool breeds, on the other hand, have long wool (longer than "longish"), typically 6 – 12 inches8. Border Leicester has "long, lustrous, curly" staples of 6 -8 inches; English Leicesters - the wool is long, heavy and lustrous, 6 inches and up; Lincoln - the wool is described as very long, strong and lustrous, 7 – 10 inches9. As an interesting side note, Soay and North Ronaldsay sheep, both thought to be more primitive than the Shetlands, have fleece ranging from 2 - 4 inches10.

In general terms, fleece from 3 inches to 6 inches is probably within the range implied by "longish".

There will also be some interaction here with the extra fine criteria. Usually, as the staple length of natural fibre gets longer, its diameter increases as well11. If the wool is supposed to be extra fine, it is not likely to be growing up into the 7 inch and up range of the longwools.

Wavy: This characteristic is usually equated to crimp and is also best understood as encompassing a range. Some references specify 9 - 10 or 8 – 12 crimps per inch as appropriate12. Other articles just say "well developed crimp"13. In any case, the extremes of straight fleece with no crimp and the very high frequency, low amplitude merino style crimp are both outside a reasonable interpretation of "wavy".

In addition, crimp and fibre diameter in wool are highly and inversely correlated14. This means that if you have more crimps per inch, you will generally have a finer fibre diameter; less crimps per inch usually indicates a higher fibre diameter. So, if the wool is in the extra fine range, it will have noticeable crimp.

Well Closed: This criteria can be taken to mean that the staples are well closed (tapered to a tip) but more probably means that the fleece as a whole is well closed - dense15. Density is important to sheep exposed to climate extremes, especially if they do not have shelter, first class forage or feed additives provided to them. This, then is one of the components of preserving the hardiness of Shetlands. Sheep with thin or scant fleeces require more feed and more shelter to maintain condition and the return from the sale of their fleeces will be less. If you can easily part the fleece and see a noticeable line of skin without wool follicles, the fleece is lacking in density. The less skin to be seen, the better, with this test. Another subjective way to gauge density is to feel a handful of fleece; a handful of a dense fleece should fill your hand and make it harder to close because of the abundance of the wool.

Wool on forehead…: This portion of the Breed Standard fleece criteria does not deal with fleece
quality and so will not be discussed further, other than to say the wool should be there

Additional Characteristics to Consider:

Tapered Lock Structure – this may have some connection to the "well closed" fleece criteria. In general, Shetland staples should not be flat across the end and should not have a long extended tail of hairy fibres extending out past the main body of the staple. Rather, the wool should taper to the end of the staple making a tip16. This may also be described as feathering. This comes from having some variability in the fleece and may relate to the Shetland’s ability to withstand extremes in temperature and rainfall. The length of taper will vary with staple length. Rooing may accentuate the tapering or feathering17.

Ease of Drafting or Spin-Ability - this is more a handspinners criteria but is very relevant in assessing a quality Shetland fleece. In the drafting process of spinning, the fibres are pulled past one another. Shetland fleece should draft easily and smoothly. If the fleece is sticky or cotted or will not pull easily, spinning will be more difficult, fibres will break and the resulting product will not be as high a quality. The old Bradford Count system of assessing wool was in fact a performance measure of how well a fleece would spin18. This had to do with fineness and lock structure in most cases but also, the ease of drafting and spin-ability of the wool played an important role in obtaining a good Bradford Count number.

End Notes:

"Origin and History of the Primitive Coloured Sheep Breeds of Britain", Dr. David J.J. Kinsman, The World of Coloured Sheep, 6^th World Congress on Coloured Sheep, 2004, page 15; based on an analysis of genetic information, an estimate of introgression of alleles originating with "improved breeds", probably dating from Roman times to the present, to Shetlands is 46%. This compares to an estimate of 24% for the Soays and 47% for the Hebrideans. Also see "Scrapie Genetics", Mary Castell, The World of Coloured Sheep, 6^th World Congress on Coloured Sheep, 2004, Page 134, Table 13; and "A Contentious Breed", NASSA News, July 2002, George Benedict, pages 1 and 4.
Encyclopedia of Handspinning, Mabel Ross, 1988, Appendix IX, Page 219; In Sheep’s Clothing, Nola Fournier and Jane Fournier, 1995, Page 114; Raising Sheep the Modern Way, Paula Simmons, 1989, Page 36; R.H. Lindsay Company, Wool Merchants ; British Coloured Sheepbreeders.
The Sheep That Grow the Wool, American Wool Council, 1992.
Characteristics of Wool Fact Sheet, American Wool Council, 1993.
Alpaca and Llama Fibre Production, Cameron Holt, 1999, Pages 41 – 45.
Shetland Sheep Society Breed Standard Interpretive Notes, May 2002, referring back to a publication in 1927: 3 – 5" is the suggested interpretation with no Shetland having a staple of 7".
In Sheep’s Clothing, Nola Fournier and Jane Fournier, 1995, Pages 85, 120-121; The Sheep That Grow The Wool, American Wool Council, 1992; Encyclopedia of Handspinning, Mabel Ross, 1988, Appendix IX, Page 217.
Handspinner’s Handbook, Bette Hochberg, 1976, Page 27; Encyclopedia of Handspinning, Mabel Ross, 1988, Appendix IX, Page 218.
In Sheep’s Clothing, Nola Fournier and Jane Fournier, 1995, Pages 56, 66, 70.
In Sheep’s Clothing, Nola Fournier and Jane Fournier, 1995, Pages 155, 156; "Coloured Sheep Breeds Used for Producing Handcraft Wool", Roger Lundie, The World of Coloured Sheep, 6^th World Congress on Coloured Sheep, 2004, pages 71, 80.
Wool Handling Guidelines, American Sheep Industry, November 1992, Page 1128.
Canadian Sheep Breeder’s Association Breed Standards, page 18; Shetland Wool and its Characteristics, S.H.U. Bowie.
In Sheep’s Clothing, Nola Fournier and Jane Fournier, 1995, Page 114.
Wool Handling Guidelines, American Sheep Industry, November 1992, Page 1119.
Shetland Sheep Society, Breed Standard Interpretive Notes, May 2002.
Shetland Sheep, S.H.U. Bowie; In Sheep’s Clothing, Nola Fournier and Jane Fournier, 1995, Page 114.
Shetland Sheep, S.H.U. Bowie.
Encyclopedia of Handspinning, Mabel Ross, 1988, Appendix IX, Page 32