Crazy Useful
Your Guide to the Cottage Industry Revolution
Word of the Day: Fuller
A fuller’s job is to “full” raw wool; that is, to remove the lanolin and other greasy impurities from the fibers to whiten it and prepare it for spinning and weaving. In the European tradition, this usually done through the use of fuller’s earth (a naturally-occurring clay), and fuller’s herb (also called soapwort, Saponaria officinalis). Depending on the end use of the wool, the fuller would also thicken the wool by felting it, or causing the fibers to mat together through pounding or mechanical agitation.
In Europe, the fuller was for centuries an important link in the chain of the all-important wool industry, from Medieval times to the late nineteenth century and the advent of the industrial revolution.
In modern times, the processing of wool is done by chemicals and machinery, and the fuller is no longer in the picture. However, the legacy of the importance of this cottage industry (which, in Britain, was also called “tucking” or “walking”) lives on today in the common surnames of Fuller, Tucker, and Walker.
Word of the Day: Osier
The name “osier” refers to a number of species of willow tree that produce long, narrow, flexible branches that are especially valued in basket-making. It can also refer to the branch itself (also called a “withy”).
The best-known of the species is the common osier or basket willow (Salix viminalis).
The art and craft of willow basket-making is ancient and widespread, with long traditions in Europe, East Asia, and the Americas. Willow-work is not limited to baskets, however. According to James Arnold’s book The Shell Book of Country Crafts (1968), osiers (or withies) play a role in many essential crafts including: thatching, basketry, hurdle-making (livestock enclosures), and making coracles (a type of small lightweight boat) — among numerous others.
The practice is alive and well today, though the economic and practical importance of willow-work of all types is far less than it was in previous times. Still, there is a great deal of interest in the craft, and many opportunities, especially in the United States and Britain, to learn it from experienced crafters.
Featured photo credit: The Welsh Cyntell, basket by Ruth Pybus. Photo courtesy of Potter Wright & Webb.
Word of the Day: Verdigris
Verdigris is the greenish-bluish film that is created on the surface of copper by the application of a dilute acetic acid. It has a long history of use as a pigment, in dyeing, in the arts, and in medicine.
The term can also refer to the greenish film that forms on the surface of brass, bronze, and copper as a natural result of weathering by exposure to air or sea salt. However, the chemical compositions of the natural verdigris (copper carbonate or copper chloride) and artificial are different, and only artificial verdigris (copper acetate) has the uses listed above.
The use of verdigris as a pigment and medicine dates back at least to its mention by Pliny the Elder (AD 23/24 -79) in his encyclopedic Naturalis Historia, but in all likelihood goes back further than that. In the 15th through 17th centuries, verdigris in oil paint was a popular lightfast and intense green used by many well-known artists, including the Early Netherlandish master Jan van Eyck. In the city of Montpellier in France, the manufacture of verdigris was a common household industry. Montpellier verdigris, renowned for its quality as a pigment, was made by exposing copper strips to the vapors arising from distilled wine.
Through its history, verdigris has also been touted as a treatment for a wide variety of illnesses, from leprosy to infections of the skin.
In modern times, however, verdigris — mostly due to its toxicity and relative instability as a pigment — has largely fallen out of use. But not entirely: today it is found in industrial fungicides, as a dye, and architecturally as a patina for copper and bronze.
Featured photo credit: The Magdalen Reading, by Rogier van der Weyden (after 1483). Courtesy of Wikimedia Commons.
Word-of-the-Day: Wainwright
A wainwright, also known as a wagon-wright or a wheel-wright, is a tradesperson who specializes in making wheels and wheeled vehicles.
For centuries, the horse- or hand-drawn wagon was the primary mode of transportation for most of Europe and Asia (and the Americas, after European introduction). For that reason, a skilled wainwright or wheel-wright was an invaluable part of any community.
According to James Arnold’s The Shell Book of Country Crafts (1968), when speaking of the farm wagons of the 19th century:
The building of a wagon or cart involved the harmonious thought and work of a team of men, each highly skilled in his department of the whole craft. Carpenters constructed the body and the under frame and it was another man’s responsibility to make the wheels, while the blacksmith produced all the forge-work, the wheel-tyres or the strakes, supporting standard for the body and sundry pieces. When everything was finished the painter contributed his share, to give the wagon its gay, proud coat of paint, so well applied as to outlive a generation of farmers, even though that wagon would spend so much of its life exposed to the heat of the harvest sun, the rains of Spring and the frosts of January.
A well-built farm wagon could be expected to last through a hundred years of hard use. At the center of this process was the wheelwright, the person responsible for making the all-important spoked wheels (which is why the two terms have become somewhat synonymous).
Try to imagine what would happen if you (assuming you’re not a wheelwright) were suddenly asked to make a functional wagon wheel. When wainwrights were active, it took years of apprenticeship to learn the trade. There are generations of refined knowledge behind the crafting of a wheel: a deceptively simple device that became one of the foundational pillars of our modern society.
Wax
Natural wax is, chemically, “an organically-synthesized hydrocarbon generally composed of long alkyl chains with various other molecules such as fatty acids, esters, alcohols, and aromatic components.” Okay, sure. But what is wax?
Waxes are characterized as much by their properties as by their exact chemical composition. Generally, waxes are hydrophobic (water-repellent), lipophilic (fat-loving), solid at most ambient temperatures, but malleable and with a low melting point.
Natural waxes are “organically-synthesized,” meaning that every wax found in nature was originally made in the body of a living creature.
This includes the so-called “mineral waxes”: ozokerite (and its derivative, ceresine), and montan wax, both of which are found in association with lignite (coal). Paraffin wax and microcrystalline wax are derived from petroleum. Both coal and petroleum are the result of the organic matter that is subjected to heat and pressure over a long (long) period of time.
Photo credit: Ozokerite, from the collection of the Natural History Museum of Lille, courtesy of Wikimedia Commons
A large number of plants and animals (including insects) make wax, and put it to a variety of uses. Human beings are no exception.
Which bring us to our first question: What is a property of wax that humans make use of, that is not found elsewhere in nature?
Well, let’s look at the properties one by one.
Waterproof.
The hydrophobic (water-repelling) nature of wax is by far its most widely-used property. Sheep produce lanolin (also called “wool wax” or “wool grease”) to waterproof their fleece (it also has antimicrobial properties). Plants that produce wax usually do so as a means of preventing moisture loss from their leaves. Similarly, people use the wax produced by other plants and animals as an emollient to “waterproof” their own skin, by including it in products like salves and lip balms.
Interestingly, lanolin is particularly prized for this use, as it closely resembles the compounds produced by the human body for the same purpose. However, lanolin in its natural state is mixed with compounds that can cause allergic reactions. Here is a brief but informative article about using using lanolin on your skin..
And here is one of the better (among the hundreds) of books about how make your own cosmetic products from wax:
(paid link)
Wax is also one the preferred ingredients in wood polishes, which act as waterproofing for wood. Wax polishes have been around for centuries (at least) and are relatively easy to make. Here’s time-honored recipe that has been around with only slight variations for hundreds of years:
Melt one pound of beeswax in a double boiler (never, EVER melt wax over an open flame!). Add one pint of gum turpentine and remove the mixture from the heat, stirring constantly while it cools. Pour the mixture into a wide-mouth container before it fully hardens, and cover it with an air-tight lid. Apply the wax to furniture with a soft cloth. Allow the solvent (turpentine) to evaporate, then polish with a clean cloth.
Recipe taken from: Formulas, Methods, Tips, and Data for Home and Workshop by Kenneth M. Swezey, published by Popular Science Publishing Company, 1969. Similar recipes also appear in Dick’s Encyclopedia of Practical Receipts (sic) and Processes, originally published in 1863, and in Rodale’s Book of Practical Formulas (1997).
Both lac bugs and honeybees use wax to construct waterproof protective structures for their larvae. Humans use wax to waterproof fabric such as canvas sails and raingear. They also use it to create my favorite textile art, batik.
(paid link)
Let’s take a look at another fascinating property of wax.
Solid but malleable at room temperature, with a low melting point.
Again, honeybees come to mind, crafting those lovely structural honeycombs.
Humans use this property for things like the art of lost wax casting. In this technique, wax is sculpted into a form that is used to make a mold, and then the wax is melted away; the hollow mold is then used to cast molten metal (often bronze).
Here’s a book, in case you’re interested in learning more about it:
(paid link)
Though the function of spermaceti in a sperm whale’s body is poorly understood, the two main competing theories both rely on the wax’s low melting point, which keeps it liquid at the whale’s internal body temperature. One theory holds that the waxy substance acts as a buoyancy regulator, with the sperm whale able to control the liquidity (and thus the density) of the wax. The more widely accepted theory is that the spermaceti assists the whale in echolocation. Either way, something is important enough about spermaceti that a large whale has roughly 500 gallons of it in the spermaceti organ (located at the front part of the head) at any given time.
It’s hard to compete with the coolness of echolocation, but we’re going to give it a try by looking at encaustic painting. This art form has been around since at least the first century A.D. in Egypt, where it was used to paint “mummy portraits,” or portraits of the dead. This painting technique uses molten wax mixed with pigment, and is known for enabling rich, textured and luminous color.
Here’s a book, in case you’re interested in learning more about this time-honored art form.
(paid link)
Flammable.
Ah-hah! I think we might have found a property that only humans use. At least, I can’t think of any other living creature that purposefully sets things on fire — though I would love to know if there is one.
These days, candles are almost entirely decorative, but it wasn’t so long ago that they served the critical purpose of prolonging the hours in which a person could be productive.
All waxes, which are composed primarily of hydrocarbons (in the form of wax esters), are flammable, though some are better for that purpose than others. Of the “big four” most commercially important waxes (carnauba wax, candellila wax, beeswax, and paraffin), only beeswax and paraffin are widely used for their flammability. Though one exception is bayberry wax, which forms a coating on the fruit of the bayberry tree (a.k.a. the wax-myrtle or candle tree, Myrica cerifera) and is used to make the sweet-smelling bayberry candles.
So, now we have at least one property of wax that only humans typically use. But that’s not the end of our exploration of the wonderful world of wax.
Next question: How much wax does the average American consume on a daily basis?
You’re trying to remember the last time you stuck a chunk of wax in your mouth, aren’t you? You’re thinking, Who eats wax? Nobody eats wax, unless there’s some wax-eating health food craze, right?
Well, let me put it this way: Think about the last time you ate a nice, shiny apple from the grocery store, or an M&M candy, or a bar of chocolate; the last time you swallowed a pill or used a baking mix or chewed a piece of gum…Chances are, you are eating wax every day, whether you know it or not. So, how much wax?
To get an idea, let’s take a look at the most widely used food-grade wax in the world. Carnauba wax (also called Brazil wax, or “the Queen of Waxes”) is extracted from the leaves of the carnauba palm (Copernicia prunifera). In food products, the wax is used as a glazing agent, a body or mass agent (to add bulk), an acidity regulator, and an anticaking agent.
Here’s a sample of the recommendations of the CODEX Alimentarius (a collection of internationally recognized standards, codes of practice, guidelines, and other recommendations relating to foods, food production, and food safety) regarding limits on how much carnauba wax can be included in food products:
| Food Category | Maximum allowed amount* |
|---|---|
| Surface treatment of fresh fruits | 400 mg/kg |
| Processed fruits | 400 mg/kg |
| Surface treatment of fresh vegetables (including mushrooms and fungi, roots and tubers, legumes, and aloe vera), seaweeds, nuts and seeds | 400 mg/kg |
| Cocoa and chocolate products | 5000 mg/kg |
| Imitation product of chocolate and chocolate substitutes | 5000 mg/kg |
| Some confectionery products | 5000 mg/kg |
| Chewing gum | 1200 mg/kg |
| Decorations (for example, fine bakery wares), covers (not fruit) and sweet sauces | 4000 mg/kg |
| Bakery products | BPF |
| Dietary supplements | 5000 mg/kg |
| Flavoured drinks based on water, including “sport”, “energy,” or “electrolyte” drinks | 200 mg/kg |
| Coffee, coffee substitutes, tea, herbal infusions, and other hot drinks of cereal grains, excluding cocoa | 200 mg/kg |
| Ready to eat snacks | 200 mg/kg |
Source: Carnauba Wax Uses in Food: A Review
So, in things like chocolate and dietary supplements, it’s generally recognized that up to .5% of the food can be wax. According to these guidelines, if you eat, say, one chocolate bar five days a week for a year, about one and a quarter of those bars that year is pure wax. If you eat an apple every day for a year, you eat the equivalent of about one apple slice’s worth of wax.
However, in the United States, the FDA has categorized carnauba wax as “Generally Recognized as Safe” and there are no specific limits in place as to how much carnauba wax can be included in food.
Nutritionally, the wax is inert — which is why it is so widely used. Our body does not metabolize it, and it is hypoallergenic. So, it’s not doing you any harm, but it’s also not doing you any particular good. Carnauba as a food additive is mostly just there for show — and it’s a fair amount of show.
And that’s just carnauba wax. Paraffin wax is produced in enormous quantities, and put to very similar uses in food.
Think about that, next time someone asks you a silly question about how much wax you’ve eaten lately.
Next question: What the heck?
There’s one more use of wax that we haven’t talked about yet, that I’m willing to bet is not on your radar: Ceromancy (or carromancy) is the practice of divination by pouring liquid wax into water and interpreting the shapes formed, with the aim of foretelling the future.
You might think this practice (along with the many other forms of “-mancy” out there) is just fanciful nonsense, relegated to the realm of superstition and “people who don’t know any better.” But look a little deeper, and you’ll find a principle that unites humans in their never-ending quest for knowledge about the natural world. It’s the idea that there are mysterious and complex forces at work in the universe — mysterious and complex, but not unpredictable. There is an assumption at work here, that there are definite “rules,” and if we could only gain some insight into how they work, we would be able to “see the future” — that is, make predictions about what is going to happen, based on an understanding of how the world works. That is exactly the foundational axiom of the scientific method: That the laws of nature are complex, but not unknowable, and not random or changeable. It’s a pretty big assumption, when you stop to think about it.
Luckily for us, and so far at least, it seems to be true. Our quest for knowledge is not for nothing: when we wake up tomorrow, the universe will likely be operating according to the same rules as it was when we went to sleep the night before. That’s comforting, isn’t it?
When the human world feels chaotic and unpredictable and overwhelming, it’s nice to look around us at the bigger picture and know that the natural world is build on a rock solid foundation, governed by laws that are the same yesterday, today, and tomorrow. And are, within at least an important (if not infinite) range, knowable.
Isn’t that so totally awesome?
Bugs
The living creatures that we have categorized as “insects” outnumber all other species put together by…well, a lot. Frankly, if I were to give you a number, you would pretty much know that I or whoever I had gotten the number from would be mostly guessing about it. There are (as far as we currently know) around 900,000 distinct species, comprising 70% of all known species (of anything) on Earth — and entomologists estimate that we have only identified about 20% of the insect species that may exist. Insects are found virtually everywhere, adapted to a staggering variety of climates, habitats, and ecosystems. Many species are remarkable for the intricate symbiotic relationships they have formed with other species: plants, animals, other insects. And, of course, humans.
So naturally, I have some questions about bugs.
First question: If there are over 8000 insect species that are known to be edible by humans, why don’t we eat more bugs?
Around the world and throughout the centuries, hundreds of cultures have used thousands of insect species directly as food. In modern times, at least several of these thousands play an economically important role in direct food production.
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Photo: Mopane worm (Gonimbrasia belina) on a mopane tree, by JackyR courtesy of Wikimedia Commons
Take, for example, the mopanie or mopane worm. The mopanie is the larva (caterpillar) of the emperor moth (Gonimbrasia belina), a member of the surprisingly important genus Saturniidae, which we’ll see more of later. The common name is the result of the larva’s habit of feeding mainly on the mopane tree (Colophospermum mopane). The tree and the moth are native to southern Africa, and are harvested on the order of hundreds of tons per year as an important source of protein for the region, especially Zimbabwe, Zambia, Botswana, and South Africa.
Photo: The common house cricket (Acheta domesticus), by Petr Gebelt courtesy of Wikimedia Commons
The common house cricket (Acheta domesticus), native to China but now naturalized to North America and other parts of the world, has for decades in the United States been raised as food for exotic pets. Now, food-grade cricket farms are becoming the next big thing in cottage or hobby farming. Not without good reason. Crickets have a feed-to-food ratio of about 1 to 1, as compared to about 6 to 1 for beef cattle, or 1.5 to 1 for poultry. In addition, crickets do not produce greenhouse gases, and are easy to breed and raise by just about anyone, with little initial capital investment. The supply chain currently consists of small cricket farmers selling their stock to businesses specializing in processing the crickets, usually into powder (aka “cricket flour”), which is in turn sold to food producers. It’s a growing industry that I personally hope will stick around and diversify to include other insect species.
Like, for example, mealworms. Mealworms are the larvae of the mealworm beetle (Tenebrio molitor), and they are also making inroads into human cuisine. Previously regarded as a pest, since they invade and feed on stored grains, mealworms have transitioned into pet food, and now human food, where they have been a popular food source in Southeast Asia for at least a few decades.
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Photo: Mealworm (Tenebrio molitor), by Rasbak courtesy of Wikimedia commons
In for a penny, in for a pound, that’s what I say. Once you open the door to insects as food, the world becomes your oyster. Mixed metaphor, yeah, I know. But you know what I mean. If you’re interested in exploring the topic of raising insects for food, I found the little book below to be a handy introduction. It’s short and doesn’t go into a ton of detail, and doesn’t address the commercial side of farming insects at all. But it gives a good overview, and would definitely allow you to get started raising crickets and mealworms.
(paid link)
A good starting point for the exploration of the topic of bug-eating around the world is the reprint of an article found in the journal Crop Protection, Volume 11 (Issue 5), pp 395-399, titled “Insects as Human Food” by Gene DeFoliart. A free excerpt can be found here: Insects as Human Food.
Next question: Are silkworms the only insects that produce usable silk fiber?
No. Next question.
Just kidding.
The insect that we know as the “silkworm” is the larva (caterpillar) of several species of moth in the genus Saturniidae. The best known of these is the domesticated silkmoth, Bombyx mori.
Photo: Bombyx mori larvae on mulberry leaves, by Lilly M courtesy of Wikimedia Commons
This silkworm is native to China and the practice of breeding the moth to produce silk fiber (sericulture) is at least 5000 years old, and may be significantly older. Bombyx mori is now cultivated worldwide, though the top producers by far are China and India. Silk fiber is known for its durability and natural shine, both of which have made it a popular textile fiber for in Asia for millennia, and for centuries in the West since its introduction to Europe in around the eleventh century. Famously, the favored food of the silkworm is the white mulberry (Morus alba), which is why this silk is also known as mulberry silk. So, if you want to cultivate silkworms, you also have to know how to cultivate white mulberry. Can’t have one without the other.
Photo credits: (Left) Silk cocoons by Katpatuka, (Right) Raw silk by Armin Kubelbeck, Wikimedia Commons
The silkworm is one of only two cultivated silk-producing moths. The other is the Ailanthus or eri silk moth (Samia cynthia ricini), native to India, China, Japan, and now naturalized to parts of Thailand. The favored food of the eri moth is the castor plant and the Ailanthus tree (tree of heaven).
Photo credit: Ailanthus silkmoth (Samia cynthia ricini), by Hectonichus courtesy of Wikimedia Commons
The cocoons of its larvae are harvested to produce eri silk, which is more durable than that of the Bombyx mori, but has a more woolly texture. Some traditions produce eri silk without killing the caterpillar, by allowing the larva to first leave the cocoon and then unreeling the silk. In northeast India, where the tradition of eri silk originated, the cocoons were harvested mainly for the protein-rich caterpillars, and the silk was then used to weave the traditional chaddar (wrap).
In addition to cultivated silk, there is also wild silk. For example, Tussar silk (also known as Kosa silk) and Muga silk are produced by several species in the genus Antheraea within the Saturniidae family. Native to India, the moths’ cocoons are harvested from wild groves of trees that host the insects. Tussar and Muga silk is widely used in India to make the beautiful traditional sarees and chaddars.
A brief but informative overview of the different types of silk and the silk industry in India can be found on the Central Silk Board of India’s website here.
Many other insect species outside of Saturniidae also produce silk: spiders, crickets, other moths — to name a few. Some of these are being investigated as possible sources of commercial silk fiber, and it will be interesting to see where this investigation takes us in the future: Spider silk stockings? Raspy cricket surgical sutures? Who knows?
Next question: What the heck?
It’s inevitable that whenever you’re exploring human invention and the natural world, you’re frequently going to be struck with the question: How did anybody ever think of that?
For example, scale insects.
Scale insects comprise a group of roughly 8000 species of small insects in the superfamily Coccoidea, that are usually plant parasites. One of their dominant common characteristics is that the females produce a protective waxy coating that makes them looks as if they have scales (hence, the common name). I can understand how someone would look at that wax and think that it might be useful — and, in fact, it is. For example, Chinese wax, which is used to manufacture polishes, candles, and other items, is a product of certain species of scale insects native to China and Japan.
Similarly, the lac insect (Kerria lacca) native to India and Asia, produces a resinous protective coating called lac, which is the only known resin of animal origin. Lac is refined to produce shellac, a type of varnish that has many uses, including as a wood finish and a fruit wax. This characteristic has made the lac insect the most commercially important of the scale insects, with several thousand tons of shellac produced annually. Again, I can understand how a person (especially given the long history of use of plant resin) could look at bug resin and think “I can use this for something.”
Photo: Kerria lacca resin on a tree branch, by Jeffry W. Lotz courtesy of Wikimedia Commons
But, how could someone look at a tiny bug living on the roots of herbs, and think to himself, “Hmm, I bet if I squash this and mix it with aluminum and calcium salts, I’ll get a nice strong red dye.” But that’s in fact what happened (well, something like it, anyway). There is a group within the scale insects known as the cochineals, and the bodies of these species contain generally high amounts of carminic acid, which is used to make the red dye known as carmine.
The Polish cochineal (Porphyrophora polonica), native to Central Europe and parasitic to primarily the herb knawel (Scleranthus annuus), was for several centuries and through the Middle Ages of great economic importance as a source of red dye. After the colonization of the Americas, it was largely replaced by the Mexican cochineal (Dactylopius coccus) as the source of carmine. And yes, there are cochineal farmers still around in Central America today, raising the insects to produce the dye, which is still used as a food coloring and in cosmetics. If you’re thinking about becoming a cochineal farmer, though, keep in mind that the insect is parasitic to the Opuntia genus (the prickly pear cacti), so you have to live where those grow. Just FYI.
Photo: Cultivated cochineal nests on Opuntia, by Oscar Carrizosa courtesy of Wikimedia Commons
And on that note, I’ll wrap up this discussion of the fascinating and ever-changing relationship of humans and bugs. With this one final thought: of all the bizarre symbiotic relationships that exist between plants and insects, and humans in the mix, the one between the fig wasp and the fig tree strikes me as one of the more awe-inspiring. The fig wasp and fruit-producing fig tree are completely dependent on each other for the completion of their reproductive cycles. While humans have managed to breed certain varieties of figs that can be propagated without the wasp, the Smyrna fig remains firmly dependent on the fig wasp. So, next time you bite into a tasty Smyrna fig, say thanks to the tiny wasp that made it possible.
Here’s a link to a well-done video that talks about the history, nutritional value, and cultivation of fig varieties, including the relationship with the fig wasp.
The Nutritional Value of Fig Wasps
P.S. What about bees?
Yeah, bees are an awesomely big and important topic. The relationship between bees and humans is very long and very intense. So long, in fact, that there is at least one cave painting, dating to roughly 6000-8000 B.C., that depicts a human harvesting a beehive (it’s located in Cuevas de la Arana — Spider Caves — in Bicorp, Spain). We look to bees not only for the important products they make (honey, beeswax, propolis, and royal jelly), but for their even more important role as plant pollinators. Without bees, many important crops could not be cultivated (or exist at all, in some cases). Bees will appear many times in this blog, including the next entry, which will be a discussion of the topic of “Wax.”
For now, I will recommend this beautiful and practical book about modern beekeeping and the history of the human relationship with the European honeybee. It’s a fascinating read, even if you’re not into beekeeping — and if you are, it’s got a lot of great information to get you started.
(paid link)
Additional References:
(1) Encyclopedia of Insects, by Vincent H. Resh (Ed.) and Ring T. Carde (Ed.). This would seem like a crazy undertaking to try to catalog all 900,000 species of insect, but if you’re really into learning about the insect world, this is a great reference that highlights some relevant and interesting patterns. And at almost 1200 pages, it’s got great detail, too.
(paid link)
(2) I have not read the whole book, but I can tell you that it’s dense and contains more information than the average person would ever want to know about commercially producing insects as human food. If you’re not the average person, this might be a good choice for you. Just the fact that there’s a textbook on the subject is pretty cool all by itself.
(paid link)
(2) Since sericulture (silk cultivation)is mostly practiced in Asia, most of the books out there are by and for agriculturalists in Asia. Nevertheless, there was a time when the silk industry was thriving in the United States — and who knows, maybe it could be again. For a short history of silk production in the U.S. see this article.
This is a very robust and detailed manual on sericulture.
(paid link)
And here’s a lighter version, lacking the depth and detail, but still a useful overview of the practice.
(paid link)
Available now:
Crazy Useful Things: A Dictionary of Natural Resources and Their Products
This is the book that started it all, available now on Amazon.
