Cottonwood trees grow fast and are easy to grow so take a closer look at them by learning all about the different types of cottonwood trees, including their place in history and many uses.
Forming a prominent part of the natural ecosystem in the US and reaching over 100 feet tall when fully grown, cottonwoods are truly majestic trees that tend to be a real head-turner (or rather a neck-craner).
Member of the Poplar family, cottonwood trees are amongst the tallest hardwood trees that are commonly found all across North America and Europe as well as in many different regions of Asia. With a giant trunk and branches laden with brightly colored leaves, the thick foliage of these trees forms a dense canopy that spreads into an open crown. Cottonwoods trees play a very important role in maintaining the harmony and balance in natural wildlife and are a familiar sight along rivers, lakes, and streams. They are also a dominant feature in forests where they provide food and shelter for the animals and birds.
Besides sustaining equilibrium in the ecological systems, these grandiose greens are also grown for shelter, shade, wood, fuel and several other purposes in addition to also serving as truly attractive ornamental plants.
Prized for their fast growth and adaptability to different soils and climatic conditions, cottonwood trees have long been an age-old friend to the Americans. The fact that cottonwood is the state tree of Kansas is proof of how the locals hold this species in high regard.
Learn all about this valuable species and the different types of cottonwood trees in the article below. We also include the uses as well as lots of other information that will help you appreciate what a marvel these trees truly are.
What are Cottonwoods?
Cottonwoods are a species of flowering plants in the Salicaceae or the willow family. This refers to trees that belong to the genus Populus, section Aigeiros. Native to various parts of North America and western Asia, cottonwoods share many similarities with other poplars such as aspens and balsams.
These trees are deciduous, which means that they shed their leaves occasionally and become dormant thereafter. Cottonwood trees have long triangular-shaped leaves that measure up to 6 inches each and with a growth rate of almost 6 feet every year, they can easily reach heights of 40 meters (approx 130 feet) or more when completely matured. The canopy spreads to cover an area of almost 75 feet in width whereas the diameter of the trunk itself can expand to over 6 feet when full-grown.
Cottonwoods trees have distinct male and female species and the ability to produce seeds is limited to the females only. They produce vibrant red flowers that gradually transform into fluffy seeds with a cotton-like covering. Cottonwoods need proper exposure to sunlight and a humid environment in order to thrive and flourish. They prefer sandy or silty soil but grow equally well in many other soil conditions except heavy clay. These trees are hardy from zone 2 to 9 and are a common sight in New York, occurring all the way to Minnesota and areas near the Gulf of Mexico.
Cottonwood’s Place in History
During the tough years living in wild prairie plains where trees were a rarity, Native Americans derived great benefits from the cottonwood trees that would grow in the harsh conditions nonetheless. From the roots and trunks to the leaves and fruits, the locals used different parts of these trees for various purposes to satisfy different needs. The roots served as a food source for both, animals and humans whereas the bark was used as food for horses and for making medicinal mixtures for the tribesmen. Dugout canoes were produced from the trunks while the trees themselves doubled as landmarks and trail markers for the natives and travelers alike.
From the gigantic cottonwood trees, the early communities found food for their livestock and timber for their dwellings. However, in modern day society, the use of cottonwoods has shifted mostly towards manufacturing things like paper, crates, boxes, matchsticks, and plywood. But if you want to revive memories of the great ancestors or are just looking for something impressive to plant in your backyard, growing cottonwoods can be a unique way to go about it.
Types of Cottonwood Trees
Cottonwoods can be found in three different types. Although some characteristics such as high growth are common across all the varieties, they differ in other ways that include the color of leaves, soil preferences and so on. Read on to learn more.
Eastern Cottonwood (Populus Deltoides)
Native to North America, the eastern cottonwood got its name due to its huge popularity in the eastern states but it also grows throughout the central and southwestern states as well. Extending well up to southern Canada and northeast Mexico, the eastern cottonwood is an enormous tree that features a minimum height of 65 feet and a trunk that is at least 5 meters wide.
The eastern cottonwood is without a doubt, one of the largest hardwood trees found in North America. It is a riparian zone tree which means it is mostly found in areas that form the interface between land and water bodies such as rivers or streams.
The species is called ‘deltoides’ due to the triangular-shaped leaves that resemble the Greek alphabet, delta. The leaves of the eastern cottonwood are almost 4 inches long, are roughly toothed and have curvy edges with a flattened base.
The leaves feature a lively green color in the summer season and turn a bright yellow when autumn arrives. During early spring, the female species produce sleek and slender, cylindrical flowers called catkins. These are reddish-purple in color and eventually burst open to release several small seeds that contain cottony strands to help them disperse through the wind.
Quick fact: A single eastern cottonwood tree can release over 40 million seeds in a season and if conditions are ideal, has the potential to live almost 300 years!
You can identify an eastern cottonwood from the loud rustling sound that the leaves make even from a very gentle breeze.
Eastern cottonwoods are often divided into further subspecies based on the location where they are found.
- Plains cottonwoods (Populous deltoides monilifera) are found in Nebraska, Kansas, and Wyoming. The tallest monilifera in the US (112 feet) is found in Ravalili County, Montana.
- Rio Grande cottonwoods (Populous deltoides wislizeni) occur in Texas, Colorado and New Mexico. The national champion is located in Bernalillo County, New Mexico.
Leaves of Eastern Cottonwood
Young Flowers of Eastern Cottonwood
Matured Flowers of Eastern Cottonwood
Black Cottonwood (Populus Nigra)
This type of cottonwood tree is native to Europe but has spread to various other parts of the world including Asia, Africa and different areas in the US, particularly those in the west.
Populus nigra, which usually goes by the name of black cottonwood or black poplar, is a large deciduous tree. Compared to other types of cottonwood, the black poplar has a bit of stunted growth, reaching a maximum of only 90 to 95 feet high on an average.
Black cottonwood tree features a conical shape and looks simply spectacular standing upright in all its green glory.
Its leaves have fine teethed corners and can be triangular in shape or sometimes also come close to resembling a diamond shape. Black poplar is a dioecious species which means that male and female trees are different from each other. The female trees produce long tubular flowers with a hairy surface and no petals. These mature into seeds that can self-disperse with the help of wind.
Black cottonwoods thrive best in moist soils and open areas that allow it to grow rapidly. If you ever go hiking in the Rocky Mountains, take a good look of your surroundings and you will see several black poplars gracing the place.
Leaves of Black Cottonwood
Flower of Black Cottonwood
Fremont’s Cottonwood (Populus Fremontii)
Named after an American explorer in 19th Century, Fremont’s Cottonwood is sometimes also called Alamo Cottonwood. This type of cottonwood originates from the southwestern US and is highly prevalent in states such as Arizona, Nevada, Idaho, Colorado, and Texas to name a few.
A few years ago, Fremont’s cottonwood was believed to be the same as the eastern cottonwood but later studies found them to be two different species. It is easy to confuse both the varieties owing to immense similarities in their seed pods and flowers. However, you can easily distinguish Fremont’s cottonwood by looking at the leaf structure. In comparison to the eastern variety, the leaves of Fremont’s cottonwood are relatively small. Plus, the edges of Fremont’s leaves are less serrated. These trees can reach impressive heights in only a couple of years whereas their trunks can expand to over 4 feet in diameter.
Fremont’s cottonwoods put up a spectacular show of colors as soon as summer ends and autumn begins. From lush green to pale yellow followed by bright orange and sometimes even intense red, these cottonwoods are a sight to behold. During March and April, the trees produce fluffy catkin flowers that look like elongated strips of hanging cotton from afar.
Of all the different types of cottonwoods, Fremont’s variety is the most common for ornamental purposes. In regions such as California and New Mexico, you can see Fremont’s cottonwoods standing proudly be it near houses with spacious front/ backyards or even on various restoration sites. These trees are also planted to improve natural landscapes because they act as windbreakers and prevent soil erosion. You will also find them in playgrounds and on similar recreation sites owing to the fact that they provide good shade and shelter. So, the next time you are relaxing under a big tree in a park, look up – it might be a cottonwood.
Leaves of Fremont’s Cottonwood
Flowers of Fremont’s Cottonwood
Lanceleaf is a hybrid variety (populus x acuminata). Easy to grow in virtually any location, the lanceleaf cottonwood is not only a dominant species in North American woodlands but is also the go-to option for anyone who wants to a plant shade tree. This species adapts to most soil types and is overall a very low-maintenance tree.
Lanceleaf trees are hardy in USDA hardiness zones 3 to 9 as they prefer full exposure to sunlight. Mature trees develop a pyramidal shape with thick green foliage that turns into bright yellow as autumn arrives. The leaves of this cottonwood variety look like a lance-like form, which is where the species got its name from.
Populus angustifolia, whose common names include the narrowleaf cottonwood, narrowleaf balsam poplar and willow-leaved cottonwood, is a hybrid variety that can grow up to 70 feet tall. With slender branches laden with thin, narrow leaves, this species foliage grows in an overall vase-like style that lends the tree a very graceful look.
Narrowleaf cottonwoods have little commercial importance as their wood is often affected by canker (a fungal disease that damages the bark) and is susceptible to decay. However, they are ideal for use as shade trees or ornamental trees on large plantations. In old times, the people of the Great Plains often enjoyed the buds of this cottonwood variety as a sort of chewing gum.
Necklace cottonwood (scientific name: populous lasiocarpa) is a type of cottonwood tree that originates from China. Hence, it is commonly called the Chinese necklace poplar as well. Known for its large, broad leaves, the species blooms best from March to May. During summer season, the male tree displays a thick and dense cover of lush greens whereas the female flowers excessively until the branches are heavily laden with soft white cottony buds.
Populus heterophylla or the swamp cottonwood is a large tree that can measure over 100 feet high at maturity. Like all other cottonwoods, this variety is also dioecious, which means that male and female catkins or flowers grow on separate trees. The male catkins (staminate) are cylindrical in shape and feature a bright yellow color whereas the female catkins (pistillate) or mostly green in color.
In general, the swamp cottonwood is a rather rare species in the United States except in Utah and Illinois where it can be easily found near wet areas such as natural lakes, swamps and the likes. Other common names for populous heterophylla include downy poplar, river cottonwood and swamp poplar.
Uses of Cottonwood Trees
As Street Trees
Cottonwood trees are commonly used as street trees in various parts of the world given that the environmental conditions are suitable for their growth. This is because these trees not only look beautiful but also provide great shade. Their incredible growth rate coupled with low-maintenance needs makes them ideal for creating an urban jungle.
For Ornamental Purposes
Cottonwoods look really attractive with their white fluffy cotton ball flowers hanging from a colossal tree against a backdrop of large green leaves. With the visual appeal that they add, it is no surprise that different species of cottonwoods, as well as their cultivars and hybrids, are often planted by homeowners with a large expanse of land or a vast area dedicated for gardening.
For Timber Production
Given their rapid growth pattern, cottonwoods are often planted with the objective of collecting wood from it later on. In less than a decade, a cottonwood tree can yield a large amount of wood that can hardly be obtained from any other source in the same time period. However, although cottonwoods are a type of hardwood trees, their wood is relatively soft and fibrous. This makes it suitable for manufacturing cheap but sufficiently strong items such as shipping crates and pallet boxes.
Restoring or Improving Natural Land
The enormous, deep-reaching roots of cottonwoods hold the soil in place, making it perfect for reducing soil erosion as well as slowing down floodwater runoff. Moreover, these trees are a habitat for wildlife and therefore, promote a healthy ecosystem.
Cottonwood poplars are highly popular all across the US. Now that you know how to identify different types of cottonwood trees, try counting them the next time you go on a drive or hike in the wilds.