Crazy Useful Thing of the Day: Indigo

Seed pods from Indigofera tinctoria.
Indigo (Indigofera tinctoria)

Indian indigo, also known as true indigo (Indigofera tinctoria) is a species of shrub in the pea (Fabaceae) family, of unknown origin.  It has become widely naturalized to tropical and temperate Asia, as well as parts of Africa.  It has a long history of cultivation and was the original source of the blue dye called indigo. Other species within the Indigofera genus have also become widely naturalized outside of their native regions, and are cultivated to produce both tannin and indigo.  Notable examples are anil indigo (I. suffruticosa, native to the Americas), and Natal indigo (I. arrecta).  As a legume (a nitrogen-fixing plant), it is often used in crop rotations to improve the soil.

Fabric dyed with natural indigo.

Fabric dyed with natural indigo.

Featured image: Indigo dye is made from the seed pods of Indigofera tinctoria. Photo courtesy of Shutterstock.

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Masters of Cottage Industry: Blue Ox Millworks

Welcome to the Craftsman’s Shire: Blue Ox Millworks’ Blacksmith shop, with the original sawmill in the background.

The Shingle Shack

Eric Hollenbeck and the Blue Ox Millworks are as familiar names to the residents of Humboldt County, California, as those of muralist Duane Flatmo and Kinetic Sculpture Race founder and impresario Hobart Brown. And yet, in spite of the fact that I was raised in Eureka and have lived in Humboldt County for a few decades all told, I have never visited Blue Ox Millworks. Until last week. Why? Because I’m stupid, frankly.

Blue Ox Millworks Workshop and Museum

Blue Ox Millworks’ combination museum and workshop. The “youngest” machine is the circular saw to the right, from 1938. In the foreground are my personal favorites, the collection of pedal/treadle scrollsaws, and the levered shaper that makes perfect Gothic arch fence pickets in one simple elegant motion.

I’m not a woodworker, but this is the biggest lathe that I personally have ever seen.

During the brief guided portion of my tour of the Blue Ox, Eric explained to me that this enormous workshop serves three functions: as a working job shop, where they do custom woodwork for new construction and restorations around the U.S.; as a museum, with an enormous collection of antique human-powered tools; and, for the past twenty years, as a pathway school for high school students who either have or are in danger of dropping out of school. Of this last, Eric explained, “We’re the carrot,” meaning, they make a deal with the kids that if they go to school at least three days a week, they get to come to Blue Ox and work in the traditional art of their choice. Teens who participate in the school program have many traditional crafts to choose from, including lathe work, printing, ceramics, stained glass, and blacksmithing.

The shop floor (or some of it, anyway.)

One of the many type sets from the Printing Shop. Students from the Pathway School make their own yearbooks here.

The Craftsman’s Apothecary. At Blue Ox, they make their own stains and varnishes from age-old ingredients like Dragon’s Blood, Oak Galls, and Pine resin.

The view over the bay, from the Sign Shop

Just to give you a sense of the reputation of the place: in 2014, Eric and Blue Ox Millworks were commissioned to help build a replica of the hearse that carried Abraham Lincoln’s body. The occasion was the 150th anniversary of Lincoln’s assassination, and the hearse was to be a centerpiece in the commemorative procession. Eric used to opportunity to launch a program for Veterans, in partnership with the local College of the Redwoods. According to Eric, all they had to go on to recreate this vehicle was the single surviving photograph of the hearse from 1865, and the measurement of the diameter of the wheel. It took the Blue Ox team of Veteran craftsmen a year to complete the wooden frame and chamber, as well as the decorative metal castings (other craftsmen from around the country contributed the wheels, chassis, finish, and other fittings and embellishments).

The replica of the Lincoln hearse when it left the Blue Ox Millworks. Photo courtesy of Blue Ox Millworks.

A number of craftsmen teams contributed to the final product, shown here in the procession in Springfield, Illinois, in May 2015.

It quickly became apparent to me, that Blue Ox Millworks is not just about the technical aspects of traditional craftsmanship. What Eric and his wife Viviana have created over the past forty-six years is a world in miniature, a model of the craftsman’s revolution, a reflection of a vision of the natural world as a friend and ally, to be welcomed into the workspace. Where materials and people of all stripes are welcomed and put to work for the good. By the time I left Blue Ox Millworks, I had the feeling of having visited a world that I really wanted to live in, that I would be very happy to have come to life everywhere, and for everyone. That’s probably not possible. But it’s inspiring to know that at least two people have put their hearts, souls, and hands into making it real, at least in this beautiful little corner of the world.

The historic park at Blue Ox Millworks, includes a slew (or skid) of old logging camp buildings.

The outbuildings include a ceramics workshop, a stained glass studio, and a blacksmith’s shop.

The Earthen Oven at Blue Ox Millworks
The earthen oven at Blue Ox Millworks, made in conjunction with students from Humboldt State University’s Appropriate Technology and Whole Earth Engineering courses.

The library/main office of Blue Ox Millworks.

A photo of Eric Hollenbeck in the Main Office.

Crazy Useful Thing of the Day: Bambara Groundnut

Bambara groundnut
The Bambara groundnut (or Congo goober).

The Bambara groundnut, also known as the Congo goober (Vigna subterranea), is a species of annual plant in the pea (Fabaceae) family, native to tropical Africa, but now cultivated in many tropical regions; it is particularly important in West Africa.  It is closely related to the cowpea (V. unguiculata), adzuki bean (V. angularis), and mung bean (V. radiata). Like the peanut, the groundnut is characterized by geocarpy, where the flower head of the groundnut buries itself in the soil and there ripens into an edible seed. The plant can tolerate high temperatures and marginal soils where other legumes can’t grow.  This, along with its high nutritive value, makes it the third most important legume in semi-arid Africa.

Bambara groundnut (Vigna subterranea)
Bambara groundnut (Vigna subterranea). Photo courtesy of

Featured image: The bambara groundnut (Vigna subterranea). Photo courtesy of shutterstock.

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Word of the Day: Hori Hori

Nisaku hori hori gardening tool

The hori hori is a gardening tool, a kind of short knife with a double-edged blade serrated on one side, with a semi-sharp point.  It originated in Japan, and most commercial hori hori for sale are still made there, for example by the Japanese DIY tool manufacturer Nisaku.

The exact history of the tool is unknown, but it is known to have been in use since at least the 13th century in Japan.  At that time, it was the tool of choice for harvesting sansai, or mountain vegetables–that is, wild vegetables that grew and were harvested from the boundaries separating farm and forest.  Red Pig Tools’ website has an interesting short article on some of the theories surrounding the invention of the hori hori.

The hori hori is still in use today, mostly as a gardening tool, but also among modern-day foragers.  It is listed as a “must-have” tool in John Slattery’s wonderful book Southwest Foraging (published by Timber Press in 2016).

Featured image: A modern hori hori gardening tool knife, made by Nisaku. Photo courtesy of

Crazy Useful Thing of the Day: Kapok

Kapok tree (Ceiba pentandra). Nassau, Bahamas.

The kapok, or silk-cotton tree (Ceiba pentandra) is a species of tropical tree in the mallow (Malvaceae) family whose native range is thought to be Central and South America.  It is now widely naturalized to and cultivated in the tropics, particularly Southeast Asia.  Kapoks are some of the largest trees in the world, as high as 250 feet, with buttressed trunks that can be up to 19 feet thick (or more), above the buttresses. It’s cultivated mainly for the highly useful fibers harvested from the outer casing of the seed. In addition, its edible seed oil also has potential as an alternative to petroleum-based fuel. According to the folklore of Trinidad and Tobago, the demon of death (Bazil) lives in a huge kapok tree deep in the forest, where he was imprisoned, thanks to the clever trickery of a common carpenter.

Kapok seed pods showing fiber.
Kapok seed pods showing fiber. Photo courtesy of

Featured image: A kapok tree (Ceiba pentandra), in Nassau, Bahamas. Photo courtesy of Wikimedia Commons.

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Word of the Day: Strake

Old wagon wheels with strakes.

A strake is a section of iron laid around the rim of a wooden cart of wagon wheel.  The purpose of the strake is to protect the wooden rim from damage.  The manufacture of the strake is the domain of the blacksmith, where the construction of the wheel itself if made by the wheelwright (also known as the wagonwright, or wainwright).

The word also applies to mining, where a strake is a trough or (originally) a pit with two boards laid across the bottom, used for washing ore.

A strake for washing ore.
A strake for washing ore. Photo courtesy of

The word is also used in shipbuilding, where the strake is the planking (wood) or plating (metal) forming the outer skin of the vessel.

Strakes on a ship's hull.
Strakes on a ship’s hull.

Additionally, “strake” is used in the aviation industry to refer to a type of aerodynamic surface mounted on an aircraft fuselage to fine-tune the airflow.

Strakes in the aviation industry.
Strakes as aerodynamic devices in the aviation industry. Image courtesy of Wikimedia Commons.

Hm.  Even though most of us have probably never heard of it in our lives, “strake” seems to be a pretty crazy useful word.

Crazy Useful Thing of the Day: Sorghum

Sorghum (Sorghum bicolor)

Sorghum (Sorghum bicolor), also known as great millet or durra, is a domesticated species of cereal crop in the grass (Poaceae) family.  It is the single cultivated species within the genus Sorghum.  Wild sorghum is native to Africa, where it was originally cultivated and domesticated about 5000 years ago.  Domesticated sorghum is now the fifth most important cereal crop in the world, and has a number of uses. The sweet sorghum cultivars within the subspecies bicolor are variously grown for fodder, food, syrup production, and ethanol production.  The Sudangrass cultivar in the subspecies drummondii is widely grown as animal forage.  More recently, the stalks remaining after the grain is harvested are being used to make a pressed board building material.

Featured image: Sorghum (Sorghum bicolor). Photo courtesy of Shutterstock.

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Word of the Day: Collier

Charcoal seller from 1960's on Mauritius

A collier is a person whose occupation is to procure or sell coal.  Formerly, the term applied to a person who made and traded in charcoal.  For centuries, charcoal was fuel of choice for many cottage industries.  Charcoal is mostly pure carbon, made from wood whose moisture content and impurities have been removed through a particular process of slow-burning.  This is often done by creating a “pile,” which allows the collier to carefully control the supply of oxygen to the burn.  The benefit of charcoal is that it allows for hotter fires with a smaller amount of material than does raw wood.  This made charcoal highly desirable for household use such as cooking and heating, and for industrial uses such as smelting, forging, and glassmaking.

Traditional charcoal pile
A traditional pile for making charcoal of oak and beech. Photo courtesy of Shutterstock.

Featured image: A collier (charcoal seller) from the 1960’s on the island of Mauritius.  Photo courtesy of Vintage Mauritius.

Crazy Useful Thing of the Day: Cod

Image of cod

Cod is a name that refers to the two species of fish in the genus Gadus, in the Gadidae family. They are the Pacific cod (G. macrocephalus), and the Atlantic cod (G. morhua).  Of these, the Atlantic cod is by far the most intensively commercially fished.  It is highly valued for its meat, which is rich in vitamins A and D, and the omega-3 fatty acids EPA and DHA. In addition, the liver is processed to produce cod liver oil, a popular dietary supplement since at least the time of the Vikings.  During the 19th century it was given to children to prevent rickets (a bone deformity caused by vitamin D deficiency). Today it is taken as a prevention against heart disease due to high cholesterol.

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Crazy Useful Thing of the Day: Mangosteen

Purple mangosteen
Purple mangosteen

The mangosteen is a species of evergreen tree in the Clusiaceae family, native to Southeast Asia, but now cultivated in several other tropical areas.  It is cultivated for its edible fruit, the purple mangosteen.  It is the most widely cultivated species within the Garcinia genus, though many other species also produce fruit and are grown for local consumption.  The mangosteen is closely related to the gamboge trees (G. hanburyi and G. morella, both native to India), whose resin is used to make the yellow pigment of the same name. Gamboge is famous as the dye used to color the robes of Buddhist monks.

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