How Cotton Grows On Trees (And How Long It Takes)
For all of those cotton shirts you have in your closet, you may have wondered just where the heck that material came from. Does the cotton from clothing come from cottonwood trees, though? And, if not, where does it come from, and how does cotton grow?
The cotton in our clothing comes from the cotton plant, which is pruned as a shrub and prevented from growing into a tree. When the plant is mature, the cotton bolls crack open to reveal the cotton fiber. Cotton plants take roughly 5-6 months to mature and can grow into small trees up to 6ft tall.
Keep reading to find out what the cotton plant is, how cotton grows, as well as how cottonwood trees create their cotton-like seeds!
What Is The Cotton Plant?
The cotton plant is part of the Gossypium genus of flowering plants, which belongs to the Mallow or Hibiscus family. This plant family contains around 4,225 trees, shrubs, and herbs. Cotton is considered the fruit of the cotton plant.
Commercially, four types of cotton are grown around the world, which includes the following:
- Gossypium hirsutum, which comprises 95% of all cotton grown in the United States.
- Gossypium barbadense, which is used in some of the most deluxe fabrics.
- Gossypium arboreum, which is often found in the fabric muslin.
- Gossypium herbaceum, which is usually spun into yarns to produce various fabrics.
Originally, cotton was a perennial plant until humans began harvesting it as an annual. Perennials, like the cotton plant, generally live beyond two years. In addition, the cotton plant is typically maintained as a shrub; however, if it is not maintained, the plant can grow in size and become a tree.
Cotton plants need extensive heat and an environment that is free from frost to grow. During spring, farmers plant cotton seeds to optimize their growth potential. If the plants are not harvested by November, the colder weather and frost can denigrate their quality.
The Difference Between Cotton Shrubs And Trees (Growth Rate)
As previously mentioned, the cotton plant is typically maintained as a shrub, but it can become a tree if it is not maintained. What is the difference between a shrub and a tree, though? It is interesting to note that the word “shrub” is not a scientific designation; in fact, it is a blanket term for any plant that has at least two stems and is often less than 20 feet tall.
The difference between shrubs and trees is straightforward. A tree is defined by its larger size and singular woody trunk. Shrubs are smaller, of course, but they still need to be taller than one-and-a-half feet to avoid being defined as a simple or creeping plant.
For reference, most species of cotton plants only grow up to 6ft tall, while cottonwood trees can grow up to 100ft at full maturity. Cotton plants take up to 6 months to grow, while cottonwood trees grow 4-5ft annually and can take up to 50 years to reach adulthood.
The primary difference between species of cotton plants and cottonwood trees is their harvestability, which we’ll discuss below. But cotton plants are smaller, and produce cotton faster than cottonwood trees, which is why they’re used commercially.
How Cotton Shrubs Become Cotton Trees
Although a shrub like the cotton plant can grow into a tree, it can be impeded from doing so. For instance, if the cotton plant is consistently cut back and reduced in size, it will reveal a lot of stems. Over time, those stems will keep growing in their shrub-like form even as some of the stems naturally die and the healthier ones continue growing.
For a cotton shrub to grow beyond that shrubby status, it usually needs plenty of sunlight and space to expand. In a woodland environment, for example, a hawthorn is often in its shrub form as part of the forest undergrowth. If that same hawthorn was transferred to an open field, it could grow with up to two stems and become a tree.
A cotton shrub that has been intentionally pruned by people and then allowed to grow into its tree form will still produce multiple shoots from the stool, which is the base of the plant. Remember, cotton plants will only grow up to 6ft tall when unmaintained. So they truly border on being classified as a shrub or tree.
If trees that reach significant heights such as beech, sycamore, and oak have been cut back and then ignored, they will often grow and reassert their tree status; additionally, they will likely have at least two primary stems. This pattern has been observed through the practice of coppicing in a woodland, which is a type of forest management.
Moreover, other trees that reach significant heights such as sweet chestnut, ash, and oak have a positive response to coppicing. Through managing the plants in this way, they remain as shrubs and their many stems can be harvested on a 15 to 30-year cycle. These stems are used to create products like firewood, wooden furniture, and charcoal.
How Does Cotton Grow?
Cotton seeds and fabric that are 7,000 years old have been discovered in caves throughout Mexico. This demonstrates that cotton has been grown by people for a considerable length of time. Cotton continues to be harvested in India, Africa as well as North and South America.
As a fabric staple, cotton-based clothing is often worn during warmer seasons because of its breathability and featherweight qualities. Transforming the cotton from the field into someone’s summer shirt is an extensive process. To understand that process, it is vital to understand how the cotton plant grows.
The Development Of A Cotton Seed (Boll)
Cotton rises from the boll, which is the seed of the cotton plant. It takes a month for a boll to develop, and it is all that is needed for cotton production. Considering this short timeframe for boll development, farmers and manufacturers do not see the need for the cotton plant to grow into a tree and maintain it as a shrub.
Plus, farmers and manufacturers know that if the cotton plant is maintained like a perennial plant (which it naturally is), it might not have the necessary resources to rapidly grow the cotton itself. This is because the plant would likely focus on growing its branches and leaves rather than producing the bolls of cotton. It takes energy to grow the bolls, which is why the cotton plant is cut back as a shrub.
This pruning can assist in preventing diseases that might arise from harvesting the bolls after two years. It can also safeguard the cotton plant from pests that might be attracted to its tree form. Although cotton plants are harvested annually, they are considered commercial crops and rotated every year.
Growing And Harvesting Cotton
After planting, cotton plants require five to six months to grow to produce the cotton fiber within the bolls. Typically, the bolls will crack open, revealing the cotton fiber. This indicates that the cotton plant is fully mature and ready for harvesting.
Once the cotton is deseeded and cleaned, any remaining fiber (which protects and assists in propagating the seeds within it) is spun out with a spinner. This is the cotton ginning process. Even though cotton gins have changed in speed and size, their essential function has not changed since they were first invented.
Cotton is fairly simple to grow, but home growing is regulated and even illegal in some states. For example, hobby cotton seed is required to originate from a state-certified source in California. Additionally, it can only be legally grown in that state between March and October.
The reason there are strict regulations regarding home growing cotton is because of a governmental effort to eliminate the cotton boll weevil. This beetle has been a debilitating pest in the agriculture world for decades. The insect feeds on cotton and maims the cotton plant.
Some states expect citizens to acquire a permit to certify that they are only growing a minimal amount of cotton that will not be commercially sold. Other states have citizens sign up for an educational course that discusses how to manage the cotton boll weevil. In any case, potential home growers need to check with their nearby extension offices to ensure that they are fully informed.
Do Cottonwood Trees Produce Cotton?
Cottonwood trees produce a fluffy fiber each year after they reach maturity. It is a common sight in the spring and summer to see the trees disperse their seeds, which look like a warm-weather snowfall of sorts. Although they produce these seeds each year, the trees also alternate each year by dropping the seeds. They alternate in this way to save up their resources.
Cottonwood seeds are covered with cotton-like fibers that can look similar to the cotton from the cotton plant. Cottonwood seeds are a different substance than the cotton used for clothing, though.
In some cities and neighborhoods in the United States, cottonwood trees are banned. This is part of an attempt to reduce the messiness of their cottony seeds. Although some people and places do not embrace cottonwoods, the tree remains immensely valuable on a historical and ecological level.
Check out this article on the 14 Dirtiest and Messiest Trees to Not Plant In Your Yard for other trees that may be a potential bother to your neighbors!
Facts About Cottonwood Trees
Cottonwoods are shade trees that belong to the Poplar family. American Indians used the trunks of cottonwood trees to create dugout canoes. The bark from the tree was used as medicinal tea as well as food for horses.
There are three types of cottonwood trees in North America, which include the following:
- Populus deltoides (eastern cottonwood), which is found in southern Canada and the eastern United States.
- Populus balsamifera (black cottonwood), which is found to the west of the Rocky Mountains.
- Populus fremontii (fremont cottonwood), which is found in California, Utah, Arizona and northwestern Mexico.
Populus deltoides, or eastern cottonwood, grow in various types of soil. It grows best in moist ground or near the bottoms of rivers, and the tree does not do well in the shade. All three types of cottonwood trees can grow by six feet in height every year, which earns them the title of the quickest growing trees in North America.
An immature eastern cottonwood tree displays greenish-yellow bark that will darken as it ages. If saplings are connected to a constant water supply, they will grow between 30 and 50 feet in five to 10 years. This is when they have attained maturity, and female trees will start releasing their cotton-like seeds into the community.
The Difference Between Male And Female Cottonwood Trees
Male cottonwood trees create catkin flowers – just like female cottonwood trees – as well as pollen. This pollen is usually purple and can stain surfaces like concrete if the pollen is left unattended and becomes wet. In fact, due to the pollen from male cottonwoods, the trees are banned in places like Albuquerque, New Mexico.
Not only are male cottonwood trees banned in some places, but all-male varieties of poplar are banned, too. This is because the pollen from these trees can severely interfere with allergies. There are several native species of poplar, however, that are not banned in these areas.
Female cottonwood trees also create catkin flowers with one difference: these flowers produce cotton-like seeds. The cotton-like substance allows the seeds to travel far from the tree. This cottony substance also prevents the seeds from falling to the tree’s base.
Flowering for both male and female cottonwood trees happens in the spring. The male buds grow earlier than female buds; comparatively, they are larger as well. Female catkins are pollinated by male catkins through the wind.
Cottonwood Seeds Can Travel For Miles
Through the wind’s assistance, cottonwood seeds can travel for miles and cover all things in their path. The cottonwood tree is named after its signature cotton-like seeds. The numerous seeds can irritate allergies and sometimes be hazardous due to being easily flammable.
Cottonwood seeds grow in capsules that are found on the trees’ catkins, which are a group of flowers that hang from cottonwoods. When cottonwoods are between five and 10 years old, they start creating seeds, and their fertility increases until they reach maturity. The dispersal of seeds usually happens between one to two months after flowering.
Cottonwood seeds are dispersed between early April and July, which is when female trees create the seed capsules. When fully mature, the capsules burst open, and the tree releases the cotton-like seeds. This dispersal season can vary depending on the location of the cottonwood tree.
One cottonwood tree can disperse over 25 million seeds. The cotton-like seeds must land on the appropriate surface to germinate. Seeds are only usable for up to two weeks, and they are more likely to germinate if they land on moist soil that is exposed to ample sunlight.
Some seeds can sprout within one day of their landing, and they can expand up to a quarter of an inch in this timeframe. To reach the sapling stage, seedlings require their landing location’s soil to be consistently moist and accessible to sunlight. The reality for many of these seedlings, however, is that they are eaten by herbivorous animals, pushed out by other plants, or swept away by rainfall.
That’s A Wrap!
Even though cottonwood trees create cotton-like seeds, it is a different substance than the cotton found in clothing. The cotton plant that creates this cotton is often maintained as a shrub to capitalize on its cotton production. The cotton bolls break open when the plant is mature, which reveals the cotton fiber inside.
While the cottony seeds from cottonwood trees may be a nuisance for some places and people, the tree has a long history of use by American Indians. This includes utilizing the trunk as a dugout canoe and applying the bark as a medicinal tea. It is a meaningful reminder that all plants, whether it be the cotton plant or the cottonwood tree, can offer benefits to those who seek them.
Geisseler, D., & Horwath, W. R. (2013). Cotton production in California. USDA, CA.
Johnson, R. L. (1965). Regenerating cottonwood from natural seedfall. Journal of Forestry, 63(1), 33-36.
Mahoney, J. M., & Rood, S. B. (1998). Streamflow requirements for cottonwood seedling recruitment—an integrative model. Wetlands, 18(4), 634-645.
Oosterhuis, D. M. (1990). Growth and development of a cotton plant. Nitrogen nutrition of cotton: Practical issues, 1-24.
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