The History And Benefits Of Merino Wool


Merino wool is the exquisite, finely spun fiber from the Merino sheep, practically beyond reproach when it comes to insulating the body from the cold—and incredibly, the heat, even when it’s wet. It has been around for centuries, its rich history steeped in warfare and politics unbeknownst to quietly grazing flocks of sheep dotting the landscape, but only lately has it come into its own as a thoroughly modern performance textile, one that moves and breathes as do the very animals who wear it to begin with. And we love knowing part of the Merino story unfolded right here in our home state of Vermont. We’re not being sheepish: read on to learn all about this winsome material that is somehow at once both elegant and utilitarian.


What Exactly Is Wool, Anyway?

Strictly speaking, wool is a general term describing fibers spun from the hair of any of several mammals—sheep to be sure, but also alpacas, goats, llamas, vicuñas, and even rabbits (think Angora). Lambswool specifically is produced from a lamb’s first shearing, which usually happens around seven months. It can come from any variety of sheep. But Merino wool can come only from the fleece of a Merino sheep. An adult female sheep is called a ewe, an adult male a ram. The coat of wool shorn from a single adult sheep is called a fleece: one ewe yields between 10 and 18 pounds of wool, rams more because they are larger. This is enough to make four or five sweaters after washing and processing the wool.

What Is Merino Wool?

Merino Sheep = a specific breed of sheep that originated in Spain via North Africa

Merino Wool = the wool from a Merino sheep

Wool = spun fibers from any of several types of animals

Fleece = one coat of wool shorn from one sheep

Lambswool = the wool from the first shearing of a lamb of any breed of sheep


What Determines The Quality Of Merino Wool?

The size of the fiber determines the quality of the wool—the smaller the fiber, the higher the quality. The diameter of a wool fiber is measured in microns; a single micron is one millionth of one meter. To put this minuscule number in perspective, consider this: a single human hair is 40 microns in diameter. Insofar as wool is concerned, the number of microns describes the degree of refinement; the smaller the number, the softer and more expensive the wool. Garden variety Merino wool measures about 23 microns; “fine” Merino wool measures 18, “superfine” 16 to 17, and the ultimate—“ultrafine”—is anything under 15.5 microns. Wool between 11.5 and 24 microns is used for clothing, and the rest is consigned for use in blankets, insulation, and furnishings.

Sheepish Factoids

  • Worldwide there are over 450 sheep varieties, of which the Merino is one of the oldest.
  • Hay- and grain-fed in winter and grazing on pasture in the summer, the Merino typically yields one or two lambs a year and lives about 10 to 15 years.
  • Only male Merinos have horns; both male and female sheep of some other varieties have horns, but most sheep breeds have no horns at all.
  • Though Merino sheep are raised in nearly every country worldwide, the bulk of Merino wool—about 80 percent of it—now comes from Australia.


What Is The History Of Merino Wool?

Merino was developed in Spain between the 13th and 14th centuries when local sheep (which the Phoenicians had introduced via Asia Minor) were bred with sheep from England. But an especially meaningful chapter in the history of Merino wool was written right here in our home state of Vermont, and it all began with Napoleon. Prior to his invasion of Spain in 1808, the Merino sheep had been highly prized there, representing a substantial part of the country’s revenues—so much so it was a capital offense to export one. Faced with the decimation of its Merino flocks as a consequence of war, Spain thought better of this policy and lifted the blockade.

There were no Merino sheep anywhere in the U.S. before 1801. Then one William Jarvis, a successful American merchant and the former United States Consul to Portugal, took advantage of the sea change in Spanish policy and began introducing the sheep to the U.S., and to Weathersfield, Vermont in particular. Merino sheep are hardy and will graze on just about anything; they took to Vermont’s cold climate and its many thousands of acres of poor, rocky soil, which suited them just fine. This “invasive” species also dovetailed with an American desire at the time to establish manufacturing that would compete with and break our dependence on the Brits.

By 1837 there were over a million head of sheep in Vermont, but the boom was relatively short-lived, ending only a decade or so later when tariff laws changed, and when farmers in the American West began raising sheep for a much lower cost per head. But during its heyday, Merino farming made Weathersfield one of Vermont’s most prosperous towns.

The Vermont Merino: Looking A Gift Sheep In The Mouth

Australia was already producing Merino wool by the 19th century, but in a gesture of goodwill Vermont gifted the Aussies with a pair of Merinos that would ultimately stir controversy. The Vermont Merino was different: it had heavier, coarser wool with more lanolin. Neither did it possess the smooth, tight-fitting skin of its Australian Merino counterpart, but instead was wrinkled from head to toe.

When the Australian sheep were bred with the Vermont sheep the result was a more wrinkled Australian variety, a trait which was later difficult to breed out when it was deemed undesirable. The Australians held Vermont in disdain for some time after this controversial genetic change that ensued from a gift, calling the Vermont sheep a “white elephant.” Australia had banned the import of foreign animals prior to the introduction of the Vermont sheep for a skin disorder known as “scab,” but the Vermont Merino was ultimately seen as its own kind of scourge.


What’s Great About Merino Wool?

Here are five excellent reasons Merino wool is so desirable:

  • Merino wool is soft. Modern technology allows the selection of only the finest Merino fibers, which lack the annoying microscopic barbs other wools possess—tiny, invisible miscreants that irritate the skin. Because of this Merino feels exceptionally soft by comparison. And because Merino wool is only about a third the diameter of a human hair, it lays comfortably against the skin.
  • Merino wool drapes well. Merino is elegant and sleek and fits the human form beautifully; it also holds dye well, and comes in widely varying textures, weaves, and weights. And it’s easy to tailor—no small thing for designers—and may be permanently “set” with temperature and moisture.
  • Merino wool is insulating. The wool of the Merino sheep works to keep them warm in winter and cool in summer—why shouldn’t it do the same thing for us? This means Merino will also regulate the body’s temperature and heart rate to improve sleep. And unlike cotton and other synthetics, Merino continues to insulate even when it’s wet.
  • Merino wool keeps you dry. The long, fine, very soft hairs wick moisture away from the sheep’s skin and release it back into the air as vapor; you can expect the same when you wear Merino wool. It behaves as a buffer by managing the buildup of moisture—individual fibers can absorb as much as 30 percent of their own weight in moisture—keeping the body drier longer, whatever the external temperature. Once wet, Merino dries more quickly than cotton or synthetics, but does not cling to you, so your skin can continue to behave “normally.”
  • Merino wool is a natural performance material, possessing many of the same technical properties that must be added to other performance textiles. Merino wool is anti-microbial, resists odors, fire-resistant refusing to melt or stick to skin, anti-static and wrinkle-resistant, hypoallergenic, and boasts an Ultraviolet Protection Factor (UPF) of 50+ depending on its weave.

The end result is a beautiful, functional textile.

Merino Wool: Clean And Green

Naturally biodegradable and renewable, Merino wool treads softly on the environment. Wool decomposes in the soil in a matter of years when disposed of, slowly releasing valuable nitrogen-based nutrients back into the earth, acting as a natural fertilizer.


Where Can I Find Merino Wool?

This versatile textile comes in several smart iterations:

  • Refined Couture: for the snappy dresser, a fine Merino sweater may be worn as any other shirt, neatly tucked, with a suit or a sport jacket. Merino wool does not “pill” at all; its elegant, flat finish also keeps it from taking on the bulk of other textiles. And it retains its shape well over time.
  • Rugged Outdoor Wear: Add to these admirable traits its insulating, wicking, and water repellent properties, and Merino wool ranks high for underwear, t-shirts, base and mid layers, sweaters, jackets, and more. It has gained popularity for the outdoors enthusiast not only because it insulates and wicks away moisture, but also because it delivers a natural UPF of 50+ depending how tight its weave.
  • Hiking and Athletic Socks: Hikers and athletes alike swear by Merino wool socks, which keep the feet cooler than cotton (and other synthetic “cocktail” textiles), even in the heat. And if your feet get wet in cotton—from sweat or the environment—it soaks up the moisture like a sponge; the net effect is no socks at all, and therefore no insulating properties. Merino acts as a vehicle to disperse moisture away from the feet while continuing to insulate them.
  • Workout and Active Wear: Merino possesses a natural elasticity that allows it to bend and then return to its natural shape; together with all its other appealing character traits, this makes it an ideal performance material for your active lifestyle.

Merino wool is hands down the most luxurious wool in the world, the finest and softest grown by sheep. And while some insist cashmere is the most refined textile (and it is refined, to be sure), those in the know understand ultrafine Merino is more sublime still. It is warm, naturally insulating, water-repellent, and extremely durable, the modern go-to textile for the impeccably dressed, but also for the outdoors enthusiast, and even the athlete: versatile Merino wool knows no bounds.

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