Looking forward to growing your own locust tree? Learn about the different types of this wonderful and amazing tree. They're not just ornamentals but they have a wide span of uses too. Find out the best locust tree for you.
Locust trees belong to the pea family and are extremely fast-growing members of this family that also grow and thrive well in various types of environments. These trees are majorly found in Mexico and the eastern region of North America.
There is a variety of types of locust trees in which some are popularly cultivated as ornamentals for their beautiful looks and aesthetics while the others are grown for their top-quality hardwood. The locust wood is amazingly hard and durable and is often featured in the making of rails, buildings and fence posts.
Locust trees are simply described as deciduous trees that produce long, compound leaves, each of which has the ability to sprout a total of 21 leaflets. There are many of its species that are often armed with thorns which are typically almost three inches in length. Others give birth to beautiful and exotic flowers that are showy and full of fragrance. They are usually found hanging loose in clusters.
In case you’re thinking of planting one, or more, locust trees, there are a couple of things to be aware of to make sure your young tree grows up to be a healthy mature tree. Canker and root collar rot are common diseases affecting locust trees.
- Make sure to water your tree well during dry spells, without getting it waterlogged
- Prune infected branches by cutting at least 1 ft below the infected area
- Disinfect your pruning tools with 1 part bleach to 10 parts water
- When you’re moving around the tree be careful to protect the trunk because injuries are ideal places for disease to enter.
Table of Contents
There are many different species of the locust tree, each of which has unique features like size, colors, and uses. These qualities make them highly distinguishable from each other and also make them stand out from a lot of other trees that they might be growing with.
These are some of the most popular and common types of locust trees, in case you are looking to grow one in your lawn!
Black Locust Tree
Scientific Name: Robinia pseudoacacia
Also known as “false acacia,” the black locust, or Robina Pseudocacia, tree is a hard-wooded, fast-growing plant that is found throughout the United States and because it’s been widely planted in other temperate climates, it’s now in Europe, South Africa and Asia. In some areas it’s classed as an invasive species. This tree grows best in sunny locations, woodland areas, and along stream banks. The hardiness zone of the black locust tree ranges from 5 to 8, and it grows to an average height of 40 ft and spreads to over an area of almost 25 ft. To grow these trees, you will need loads of space, sun and good drainage. They’re almost too easy to grow so you’ll need to keep the suckers from spreading.
The black locust is a deciduous type of hardy tree and is basically a legume that grows really fast and has certain tough qualities that allow it to tolerate poor soil, drought, salt, and pollution. These trees have small green leaves that often consist of a beautiful shade of blue. The leaves grow to an average length of 25 centimeters, and they are pinnately compound, or feather like. They produce beautiful white flowers rich with an intense fragrance. Some varieties may even produce pretty pink and purple colored flowers. These flowers are often found hanging in clusters that measure between four to ten inches in terms of length.
Although black locust trees are usually planted for decorative purposes, they are more popular and much valued for their durable, hard and top quality wood. In fact, Black Locust wood is so strong it was once used to make nails for building ships. While the wood is really difficult to cut, it is an excellent choice for firewood since it is able to burn for a long time. In many regions, this plant is also cultivated as a honey plant as where its blooms is a major source of nectar for all the honeybees flying in those particular regions.
Honey Locust Tree
Scientific Name: Gleditsia triacanthos
This variety of locust tree has lots of pseudonyms and is known as honey shuck, sweet bean, and sweet locust. It is a very fast growing tree, a quality that has led it to become one of the most commonly and popularly cultivated trees for large gardens.
The honey locust tree grows to an average height of 30 to 70 feet and spreads between the range of 30 to 50 feet. Due to its fast-growing abilities, it can grow as much as 20 feet in the initial ten years and can go on to reach up to 70 feet. It is a commonly held belief that fast-growing trees have weak wood and invasive roots, however, honey locust trees do not fall in that category. They are incredibly hard-lived trees that have an extraordinary ability to tolerate compacted soils, wind storms, ice, salt, pollution, and foot traffic.
The Honey Locust tree is popularly grown for ornamental purposes since they produce very attractive and stunning fall foliage that is usually deciduous broadleaf. They have bright green leaves that are pinnately compound, and they contain little leaflets that give the foliage a very pretty, lacy effect. The lacy foliage makes the honey locust trees ideal for patios since they provide dappled shade that is ideal for shade-loving plants as well as sunbathers.
The flowers produced by honey locust trees are really small, sport a creamy-green color and give off a very strong aromatic scent. The male flowers of this plant often grow in dense clusters while the female flowers grow more towards the loosely-arranged end. One interesting fact about honey locust trees is that despite what the name might suggest, they are not honey plants. They hold this particular name because the sweetness of their pulp is popularly used in the making of different types of beer. Like black locust trees, the timber of the honey locust tree is also really hard and durable, making it a highly valuable type of wood for furniture making.
Fun Fact: The compound leaf of the Honey Locust tree are too small to pick up and because of their size they don’t cause any blockages in drains or sewage systems. This makes them extremely popular in town parks and other public areas as they require less maintenance, which equals less cost to the local municipality.
Imperial Honey Locust
Scientific Name: Gleditsia triacanthos inermis ‘Impcole’
This is known to be one of the most popular and the finest of shade trees. It has quite a ferny and a delicate appearance with a stunning greenish yellow to greenish white bloom. This is a great lawn tree as well as a street tree, considering it casts a peculiar light shade that allows the turf to grow underneath the canopy.
The imperial honey locust grows to an average height of 30 to 40 feet and spreads to over 25 to 35 feet. The bloom time for these trees is from May to June, and they grow best in well-drained soils that are moist and organically rich. They also prefer full sun and are highly resistant to saline conditions, high summer heat, drought, and heavy winds.
The imperial honey locust is a native tree from Pennsylvania to Iowa and south and further down to Georgia and Texas. It has a well-rounded, spreading, crown and its branches and trunk often consist of 3-inch long stout thorns.
Just like many other varieties of locust tree, the imperial honey locust is also majorly grown for its decorative and attractive features. It produces stunning green foliage throughout its blooming season, and its feathery looking leaves resemble a fern that starts out green and then changes into a beautiful yellow color during the fall season.
In terms of planting and growing these trees, they have a high canopy and often grow with a clearance of almost 7 feet from the ground. Like other locust trees, it is also a fast growing tree that can live up to 70 years or even more, so long as they are provided with the ideal growing conditions. It is another very strong tree and is often used in the making of furniture.
On the downside, though, this tree is highly susceptible to a great many diseases. Some of these potential diseases include canker, leaf spot, rust, witches’ broom, and powdery mildew. They might also get infected by common insects and pests like webworms, spider mites, borer, and plant bugs.
Skyline Honey Locust
Scientific Name: Gleditsia triacanthos ‘Skycole’
The thornless Honey Locust tree is another variety of the honey locust tree that grows to an average height of 45 feet and spreads to about 35 feet. It is a highly popular shade tree particularly due to its super delicate and ferny appearance. The fern-like feature helps cast a dappled shade below on the tree, which makes it stand straighter as it grows, compared to other species. It also makes for a fantastic street tree due to it being taller than it is wide and is also increasingly tolerant of adverse growing conditions. The dappling effect also means it won’t kill young growth underneath it.
Skyline honey locust is a tree that is native to North America and is basically an open deciduous tree with a highly sophisticated and unique pyramidal form. It has an excellent landscape composition due to the tree’s delicate and very fine texture, which suggests that it can be used as a wonderful accent feature just for that very reason.
This is comparatively a low maintenance tree and the best time for to prune it is late winter once the harsh cold weather has passed. The tree prefers full sunlight to be able to grow to perfection and is equally adaptable to both moist and dry growing conditions. One of the most impressive features of this tree is that it is not finicky about the soil’s pH levels and is well-tolerant to environmental salt and the effects of the urban population. It can be grown in areas where the soil is eroded or on hillsides to stabilize poor soil.
During the late spring season, a mixture of greenish-white and greenish yellow flowers appears on the skyline honey locust trees. These beautiful flowers are accompanied by dark-purplish seedpods that are long, flattened and twisted. These seedpods obviously contain seeds, but also another substance that is incredibly sweet and gummy, which is what gives these plant species their due name.
Scientific Name: Robinia hispida
This is a deciduous showy and flowering shrub that is also known as ‘moss locust’ and ‘rose-acacia.’ It is native to the Southeastern United States but is now also found as an introduced species in various other regions and areas of North America. It grows so fast it’s actually classed as a noxious weed in most of the Midwest States and you cannot grow it there.
The Bristly Locust grows to an average of 8 feet tall and wide and is considered to be more like an aggressive shrub. This shrub is usually spread by suckers and is highly invasive in Washington, Michigan, Ohio, New Jersey and Pennsylvania.
One of its characteristic and most notable features is its stunning green, compound leaves that grow on bristly stems. The leaves are coupled with rose-pink pea-like flowers that are filled with an amazing fragrance, and they greatly attract bees and butterflies during the early summer and the late spring seasons. You might often notice bright red, bristly seedpods on the flowers, too. These seedpods are what gives the tree its name and also makes the tree stand out in your garden.
The bristly locust tree grows best in loamy soils and silt loams that come with a proper drainage system. Like other locust tree varieties, its tolerance levels are not that strong, and it will only thrive well in moderately well-drained soils.
Unlike other types of locust trees, the bristly locust provides the best erosion control for those sloping sites that are greatly affected by active erosion. This is primarily because they have the ability to provide a quite thick, woody, and quick vegetation cover to all those crucial areas that are in dire need of such kind of stability.
Interestingly, in times gone by, the indigenous people belonging to the southeastern woodlands of the United States called the Cherokee, used this plant for several medicinal purposes, one of which was to relieve toothaches. They also often brewed a tonic of this plant and fed it to their cows. Other uses of the bristly locust revolved around its high-quality wood that was used to build houses, make bows, fences and blowgun darts.
New Mexico Locust
Scientific Name: Robinia neomexicana
Also referred to as southwestern locust or hojalito, New Mexico Locust is a thicket-forming and a multi-branched shrub that belongs to a genus of the pea family. The majority of the population of this locust species thrives throughout the Southwestern United States, which is one of the reasons why many people say that it should have officially been called the southwestern locust.
This locust tree grows to an average of ten feet in height and produces reddish purple branches. Beautiful pale, pink roses grow on these branches along with thick, hairy and rough beans. The New Mexico Locust is often best described as a small tree; or rather a spiny shrub that regularly forms thickets and has a wide, open crown.
The early summer season usually springs with it spectacular and breathtaking floral displays of the New Mexico Locust, especially on the northern rim of the Grand Canyon National Park. These displays are some of the reasons the tree holds incredible value as a great ornamental feature. It is also popular for various other reasons, including erosion control, root-sprouting, and the formation of stumps.
It has specific growing conditions that include dry soils, partial shade, medium water usage, and rocky, clay, clay loam, sandy, and sandy loam soils. These trees produce compound leaves, each of which consists of almost nine to fifteen leaflets. You will often notice small hairs growing on the tree’s leaves and branches that result in a distinctive grayish cast on these trees. This particular locust tree also provides grazing as cattle and local wildlife love the foliage and flowers.
Many of the locust varieties are best grown for their stunning floral displays and lush, green foliage. So, if you are looking to revamp your lawn or garden, perhaps you should grow one of the locust trees as well and witness the beauty of nature unfold right in front of your eyes!