(The thumbnail photo shows flax blooming at an experimental farm in Japan.)
Linen and hemp are often grouped together in Japanese under “asa” (bast fibers). On the other hand, coffee bags (mostly jute) and the inner batting (ramie) of some bedding are also made of hemp. Since they are often confused, let's clarify them here.
Let's take a look at what is called "hemp" today in the Consumer Affairs Agency's Textile Products Quality Labeling Regulations (revised December 20, 2021/effective January 1, 2022).
Plant fibers are divided into three categories: "cotton," "hemp," and "other plant fibers." Only linen and ramie are designated as "hemp," and hemp and jute are classified as "plant fibers."
Accordingly, on Japanese labels you will typically see ‘麻（リネン）’ for linen and ‘植物繊維（ヘンプ）’ for hemp.
(For more information, please refer to the Consumer Affairs Agency's website "Textile Product Labeling Regulations.")
Now let's take a look at the differences between linen and hemp as plants.
<Linen>
(Photo shows flax after harvest at a test farm in Japan.)
・The raw material is flax, a plant that is about 1.3m tall.
The production areas (agricultural regions) are from northern France to Belgium to the Netherlands (also called the Flanders region), as well as Belarus and parts of China. High-quality raw materials are mainly from the Flanders region (the Belgian city of Kortrijk is famous as a raw materials collection center since the Middle Ages).
・The extracted fibers are extremely soft and lustrous, so much so that they are likened to a woman's hair (the phrase "the girl with flaxen hair" comes from this image).
<Hemp>
(The photo shows hemp after harvest, laid in the field for retting — the natural separation of bast fibers.)
・The raw material is Cannabis sativa, which grows to a height of 2.0m.
・The plant is cultivated in agricultural areas including China, North and South America, Europe, Australia, and other regions, but can be grown across a wide range of climates.
The extracted fibers are very hard, almost like tree bark. However, after going through the refining process (polishing the fibers), they become a supple, soft, golden-colored fiber material.
(The photo shows hemp with the outer skin removed (Wikipedia). There is a woody core, and the surrounding bast fibers are used as raw material for yarn.)
Not only does the plant grow to a different height (1.3m vs. 2.0m), but unlike linen, hemp has a hard part in the center, which gives the plant a distinct appearance.
The kanji for hemp (麻, asa) generally means "fiber extracted from plants." The "forest" component in the kanji is said to be a pictograph of "peeling off the outer skin." It is thought that when the character was created in ancient China, hemp was probably cultivated (or harvested in the wild) as part of daily life, and the act of peeling off its surface was depicted. In modern times, hemp is not classified as "asa" in textile product labels… it feels strange to think about this when considering the history of the kanji for 麻.
Daitoh
