What Are You Cotton About?

Cotton--It's what most people first think of when asked about how plants are engrained in their daily lives (this is an unofficial survey, of course). Well, there's a reason for that. Its been around a long time, since 5000 BC, in fact.

"Open Boll" of Upland Cotton (Gossypium hirsutum)

The image above is how we typically think of cotton. But what is it, exactly?

The white, fluffy stuff is called a "boll," its made of mostly cellulose and contains the seeds of the plant. This boll is actually NOT the flower of cotton! The flower, when it first blooms, is white and turns pink when it is pollinated. After this, a hard bud called a "young boll" pushes up and knocks off the flower's petals. Then, as the cellulose fibers develop, the young boll turns into a "cracked boll" and, later, an "open boll." Inside this open boll lie the seeds, whose fibers will help them disperse.

And, there's actually more than one kind of cotton! Gossypium hirsutum (Upland Cotton, see above) is the most commonly grown cotton species, accounting for more than 90% of the world's production! But there are many other cousins to this plant, two of which we will talk about today!

Extra Long Staple Cotton (Gossypium barbadense)

Some cotton is just...better than others. That's where Extra Long Staple cotton (Gossypium barbadense, ELS) comes in. You've probably heard people praise Egyptian Cotton before, well now you've seen it! The cellulose fibers on this boll are much longer than those on Upland cotton, and are believe to make a softer, more durable fabric. Pima (or SUPIMA) cotton is made from ELS that is hand-inspected...so, it's Egyptian Cotton 2.0. But, this comes at a bit of a price, because only 8% of the world's cotton is ELS cotton!

To learn more about SUPIMA cotton, check out this video!

Tree Cotton (Gossypium arboreum)

Our final cotton is "Tree Cotton," or Gossypium arboreum. This cotton plant has bolls that grow on its 6 feet tall branches! The cellulose fibers in this variant are used to make muslin, a fabric that is known for its high strength per number of fibers. Less than 2% of the world's cotton is produced from Tree Cotton, but it was one of the most commonly used fabrics before the industrial revolution.

For more facts about cotton, check out this webpage!