“Lilly tree bearing tulips” is apparently what Linnaeus meant when he described the tulip tree as Liriodendron tulipifera, and we have been calling it all kinds of things before and after:  tulip poplar, yellow poplar, white wood, fiddle tree.  It is not a poplar, but it is in the magnolia family.

I learned a lot in forestry school, but two tree facts that stuck best in my head were related to our big trees:  sycamore and tulip tree. The sycamore is the tree in the northeastern United States with the widest girth (the biggest trunk) and the tulip tree is the tallest. Sure, we can’t compete with the redwoods and sequoias of the Pacific northwest, but we’ve still got our share of big trees around here!

The tulip tree is actually the tallest deciduous tree in North American, and it is the only species of its genus on this continent.  There is one other species in Asia, Liriodendron chinensis. The tulip tree is also one of our fastest growing trees here in the Washington, D.C. region. Often nestled in a little creek or stream valley, they grow quickly and often fool you into looking older than they really are. But their grandeur and superlative qualities belie their finer points. I’m quite fond of their simple, but peculiar blunt-tipped, four-lobed leaves, and I especially love the beautiful greenish-yellow with orange flowers.

I often challenge folks to find new ways to appreciate their trees year round. For me, I rediscovered the tulip tree several times over in my continuing education and life-long work with trees, in very different circumstances.  Once was stomping through the bitter cold of winter, crunching through an icy crust of old and frozen snow.  It was a quiet, calm winter morning, with winter shadows long through the brown and gray trunks of trees, indistinguishable at first glance.  But a little cold breeze picked up, and several large tulip trees, with their open brown seed cones, rained down hundreds of their wind-dispersed samara-like seeds, twinkling through the twigs and branches and skittering across the frozen landscape.

If you enjoy your trees while out walking around in the District, there are two locations where you can be sure to pay more attention to our majestic tulip trees: the first requires that you head south on 16^th Street NW and after crossing the hustle and bustle of U Street, take a break from the people watching and look up to see the view of the White House.  This stretch of 16^th Street NW is unique in its prominent landscape design choice, with its view-shed framed by the towering, majestic tulip tree, planted just inside the sidewalk, in the front yards or “public parking” space of those properties that line the road.  It’s a design strategy that merits application in other situations, when our street trees are either choked out by small soil volumes of the tree box, or are “reduction pruned” for overhead wire clearance—let’s plant big trees in front yards where there is space to allow them to reach their full potential.

The second spot asks that you cross Duke Ellington Memorial Bridge on a hot, humid, muggy D.C. evening between Adams Morgan and Woodley Park, and peer out over Rock Creek Park. You can see the tulip trees reaching for the sky from the park land below and enjoy a rare view looking down on their wonderful and seldom-seen flowers.

The tulip tree is the state tree for Indiana, Kentucky and Tennessee, and a couple years back, we had the pleasure of planting one in St. Paul’s Rock Creek Church Parish in memory of my friend Nick, from Kentucky.

It’s also an important timber tree, known to have some resistance to termites, and has an American Indian history of being utilized for dug-out canoes.  It is also considered a major honey plan. We frequently plant them as specimen shade trees in park and other settings where they will have plenty of space to reach their mature size.  However, there are a couple smaller-stature cultivated varieties, including the “Little Volunteer” which we have planted at Delaware Circle, and hope to promote for smaller yard plantings.

No matter where you choose to see these incredible trees, be sure to soak in their presence – and bring a camera, to help you remember until the next time you cross paths. Check out our tree species map below for other locations throughout the District:

View map full screen.

For more about tulip trees and many other species, check out the tulip tree profile on our Tree Species resource. You can also explore our Tree Talk online chats, which cover a range of topics from tree spotting and care, to species-specific discussions (such as the American elm and fruit-bearing trees).

Flickr credit: nipplerings72.

The Hawthorn tree (Crataegus sp.) harkens back to the old woodlands, farmlands, and estates of yore.  It is a tree of diverse species with many forms and characteristics. Its wildness is exemplified most by the natural forms with long, stout thorns, and twisting and turning branches that form thickets telling woodland wanderers, “do not tread here.” While wildness can be a virtue, you might prefer the more homely cultivars that have been selected over centuries of Hawthorn cultivation. Varieties have been selected to be thornless, columnar, and to have showier flowers and fruit.

The hawthorn grows native all across the temperate regions of the Northern Hemisphere. There are about 220 species native to North America alone. Many species occur only in certain places, giving many regions a native hawthorn they can call their own. Green Hawthorn (Crataegus viridis), with the now popular cultivar “Winter King” is probably the better known of the species native to our region. “Winter King” has a magnificent display of red fruit that persists further into the winter than most varieties. Its form can vary, with some cultivars staying under 10 feet, and some wild varieties getting as large as 45 feet. Hawthorns are generally considered tough species, able to deal with a range of soil conditions and drought, but they tolerate only moderate shade. Being in the rose family, Hawthorns are susceptible to some of the diseases associated with species in that family, though they are considered hardier than their cousins and with a little vigilance this tree should be no problem to grow. A healthy Hawthorn of some species can live as long as 400 years.

Hawthorn has much lore and a variety of historical uses. The traditional Mayday festival of Northern Europe was, in some places, said to fall on the day the Hawthorns bloomed, May 1^st. Its alternate name is “Mayhaw.” Hawthorn flowers decorated the woman chosen to be the “May Queen.” Hawthorn fruits, also called “haws” have been used traditionally to make jams and jellies, with the North American varieties said to be sweeter and less astringent than their European counterparts. There is a movement to expand the cultivation of some southeastern varieties of Mayhaw to a broader commercial level. Hawthorn is also prevalent in folk medicine and has been used to counteract high blood pressure, heart failure, and chest pain. Unlike many folk remedies, these effects have recently been substantiated by conventional medical research and marketing of hawthorn extract has followed.

The Latin name Crataegus means “hardness” and refers to the Hawthorn woods durability. It was used in many applications of wood demanding strength, including for the cog teeth in old wooden watermills and machinery. For obvious reasons, the Hawthorn makes for one of the most functional living fences and hedges. When the commons farmland of England was divided up and privatized in the 18^th and 19th centuries, the most popular way of enclosing land and keeping others out was to establish a Hawthorn hedge. Livestock can also be contained this way. Hawthorn is also a great wildlife plant, giving food to the birds into the winter.

So don’t let the thorns on some of those Hawthorns scare you off. This tree has a rich cultural and ecological history, is a beautiful addition to any landscape, and it could even improve your health! Look out for its red berries in the winter and its flowers coming this spring (not exactly on Mayday around these parts) with the species map below:

View map full screen.

For more about hawthorns and many other species, check out the hawthorn profile on our Tree Species resource. You can also explore our Tree Talk online chats, which cover a range of topics from tree spotting and care, to species-specific discussions (such as the American elm and fruit-bearing trees).

Flickr credit: i-r-paulus.

The American hornbeam (Carpinus caroliniana) has a variety of alternate names – “Blue Beech,” for the color of its bark, and “Musclewood” for the muscle-like ripples in the trunk. It’s a stately yet humble tree native to the understory of woods and shady areas along streams. It is a member of the birch family and has finely toothed leaves reminiscent of those of birches, though generally smaller in size.

An interesting feature of most trees in the birch family is the cylindrical, pendulous flowers with the special name “catkin.” The male catkins (which produce the pollen) of the American hornbeam differ from those of its cousin, the hophornbeam, in that they form in the spring as opposed to the previous fall. So if you see fresh catkins on a tree in the fall or winter, you can be sure you are NOT looking at an American hornbeam, but rather something else in the Birch family. The female catkins, when pollinated well, will develop into a long chain of 10 to 30 winged seeds that are a unique and aesthetically pleasing feature. The American hornbeam has a wide range, from Quebec, Canada down south to Florida and from the east coast west to Minnesota and Texas.

The American hornbeam and hophornbeam are not even in the same genus and their barks look very different, but they do share a well-deserved secondary name: Ironwood. These two species have some of the densest wood around, and were used for some roles that iron metal fills today. The name, ‘horn’-‘beam’ refers to the wood being as durable and close-grained as an animal horn. Traditionally, they were used for tool handles and heads, wooden cogs, flooring, and golf clubs for their durability, as well as for turned bowls and plates due to their tendency to resist cracking. It is also reported that trying to work hornbeam with sharp tools will dull the tools very quickly, as if you were trying to cut into iron. Because of their density, these trees can make great fire wood if they exist in abundance on a given piece of land.

In a home landscape setting, this tree thrives in shady areas – though with a little pampering and some deep, rich soil, it can be an excellent addition to sunnier areas as well. It reportedly can reach 65 feet in its natural setting but you should expect only around 35 feet or less in a domestic setting, and that much only after many years as this tree naturally grows quite slowly. When allowed to go where they will, American hornbeam grows into a variety of unconventional form, with twists and multiple trunks that can be quite lovely. If trained properly, this species can work well as part of a hedge. A close relative of our tree, the European hornbeam, has been a classic landscape tree for centuries with many cultivars. The American hornbeam has a little more wildness in its blood but is an excellent native candidate for taking an increased role in our cultivated landscapes.

If you stroll long enough along the Rock Creek Park bike path you will certainly encounter a number of American hornbeam specimens – and if you venture into to the woods a little or close to the creek, you can find them in their natural setting. You can also see two planted in front of the Casey Trees office! Stop on by and say hi.

View map full screen.

For more about American hornbeams and many other species, check out the American hornbeam page from our Tree Species resource. You can also explore our Tree Talk online chats, which cover a range of topics from tree spotting and care, to species-specific discussions (such as the American elm and fruit-bearing trees).

Flickr credit: intheburg.

The princely, slender White pine (pinus strobus) is December’s Tree of the Month, and as the winter season is upon us there is no better time to appreciate the startling beauty of this tree. What’s more, the white pine played an important role in a critical time of American history.

Pinus strobus range across eastern North America, growing in the remote wilderness of Newfoundland down to the lower reaches of the Appalachian Mountains in northern Georgia. They grow to be old and wise, easily reaching 200 to 250 years old but in some cases approaching 500 years.

The White Pine prefers well-drained soil and cool, humid climates. It is inclined to grow in the misty foothills of mountain ranges but can grow just as well in boggy areas and rocky highlands. Being somewhat resistant to fire, White Pine trees can occasionally be the sole survivors of a forest fire, and are thus able to re-seed the area rapidly.

However amazing its natural attributes are, pinus strobus are very special in another way. Before the revolutionary war, a common source of complaints against the British Crown by the colonials was about the methods that British soldiers used to cut down the tree. Pinus strobus grow very tall and very straight, and it’s strength is such that it is able to withstand heavy winds and rot. These traits made it perfect for use in merchant and warships of the time. The trees were in such high demand that the King of England made it a crime for a colonial to cut down and use a white pine. The King sent agents to place a “Broad Arrow Mark” or “King’s Mark” on the best of the White pines to ensure that the colonials would not tamper with royal property.

As it happened, the same properties valued for shipbuilding (resistance to rot, lightness and strength) were also excellent for building homes, cities, and infrastructure, and the colonials often defied the King by continuing to cut down and use the pinus strobus. The repercussions of this tension and occasional conflict were not lost upon the American colonists who eventually took up arms to overthrow the British.

In Native American history, the white pine even supplied important nutrition in times of hardship, and the word “Adirondack” is an Iroquois term that was applied to a neighboring tribe (today also known as the Algonquians) who they knew to eat the soft inner bark of pinus strobus. It could even be pounded and added to bread or other starchy foods, although they more often ended up feeding cattle and pigs instead of people.

Although normally free from many pests and diseases, white pine was quite severely struck with “pine blister” in the early 20^th century, spread by fungus attaching itself to gooseberries or wild current. Mortality from this condition reached 50-80% in mature pine groves before a laborious and concentrated effort was made to isolate and eliminate the threat. Today, pinus strobus comes in variants that are naturally resistant to the fungus and mortality rates have plummeted.

White pines can be enjoyed at any time in the year, but there is no better time to go and appreciate these historic and elegant trees than now in crisp and clear winter weather. Take a look at the Casey Trees tree map below to find out where some grow near you!

View map full screen.

For more about any specific tree species, check out our Tree Species resource, as well as our Tree Talk Thursday online chats, which cover a range of topics from tree spotting and care, to species-specific discussions (like American elm and fruit-bearing trees).

Photo credit: sandy richard.

Daniel Boone, the legendary frontiersman of colonial times, left his mark on American history as well as on November’s Tree of the Month: the American beech. Legend has it that Mr. Boone inscribed “D. Boone kilt a bar, 1803” on the trunk of an American beech tree and whether this is true or not, it showcases the rich history that Fagus Grandiflora shares with the United States.

Immense forests of the American beech tree would have greeted Mr. Boone and eager frontiersmen like him as they roamed westward after the Revolutionary War. The range of Fagus grandiflora covers most of the United States east of the Mississippi river, and magnificent forests of the beech tree could be found in Ohio, Missouri, and along the western slopes of the Appalachian mountains.

The American beech is an elegant and majestic tree that is made possible by a slender yet strong trunk that usually splits into multiple trunks halfway up the height of a mature tree. These smaller trunks then spread tall and wide to give the appearance of a large and vase-like crown. The American beech has very smooth silver-grey bark that adds to its graceful and slender shape, although this attribute can also attract bear-killing frontiersman and others to enshrine mementos with a result that looks similar to writing on paper.

Mature beech trees grow to a height between 70 and 120 feet, and it can take 300 to 400 years for them to reach this height. The leaves of the Fagus grandiflora are elliptical in shape with coarse, saw-toothed edges and are typically 3 to 6 inches long and 2 to 3 inches wide. During autumn the leaves turn to a yellow or brown color before dropping. The monoecious beech tree begins to flower in early spring and male flowers are small, yellow balls that are clustered together while female flowers are small and inconspicuous balls with red scales. The fruit of the American beech can be produced every 2 to 3 years and is an edible nut, called a “beech nut”, that is eaten by many animals.

The American beech trees prefer moist, well-drained soil that is neither too acidic nor too alkaline. It is commonly said that the first pioneers recognized that wherever beech trees grew was also the best place to grow crops because it had a reputation for growing in the best types of soil. Fagus grandiflora is the most shade-tolerant of the northeastern hardwoods and can be found in forests of final succession and is perfectly at ease in the understory of forests as well.

Beech Bark disease has remained the most significant health concern for the American beech tree. It is caused by the Beech scale insect, as it can open a wound in the tree that allows harmful fungi to enter and create cankers which can ultimately lead to the demise of the tree. Although the disease is widespread, with the proper control and maintenance procedures the disease is not as serious as it once was.

The American Beech is a very well-regarded source of timber, paper, and firewood. The furniture industry in particular made significant use of the American beech since its wood is very hard but can be bent into a wide variety of shapes using a steaming process. Fagus grandiflora is a common tree around the District, and can be seen in places like the U.S. Capitol, the National Arboretum, and Montrose Park. If you want to see it in the wild, the best place would be Rock Creek Park. For other locations be sure to check out our interactive tree map. Red dots signify trees planted by the city; green dots represent Casey Trees-planted trees.

View map full screen.

For more about American beech trees and any specific tree species, check out our Tree Species resource, as well as our Tree Talk Thursday online chats, which cover a range of topics from tree spotting and care, to species-specific discussions (like American elm and fruit-bearing trees).

Photo credit: Mr.Mac2009.

Contributing Writer: Sebastian O’Connor, Tree Planting intern

The October Tree of the Month is the stately and towering Quercus palustrus, also known as the pin oak. Perhaps one of the most abundant oaks in the United States, the pin oak can be found in almost all corners of the lower 48 states and has even adapted well to its introduction in Australia and is now common there as well. Illustrative of its large range is the pin oaks versatility where it is used by hundreds of local and city governments as canopy cover in public places such as parks, public buildings, and along streets and boulevards.

One of the characteristics that make the pin oak the tree of choice for these uses is its distinctive growth habit and handsome shape. The pin oak grows in an attractive pyramidal form with a straight and dominant trunk that firmly anchors the tree. The lower branches sweep out wide and droop slightly while the upper branches go from a horizontal to an upright angle as they reach the top.

Although the possible planting zones for the pin oak are large and varied, it is a picky tree when it comes to soil type. Quercus palustris requires an acidic, moist soil and cannot tolerate a pH level of 7 or above. Nevertheless, it is tolerant of compacted soil and urban conditions. The pin oak can even adapt to flooding conditions by developing a fibrous and very shallow root system.

Growing to a height of 60 to 70 feet, the pin oak is a medium sized tree and has broad, lobed leaves. The leaves have deep sinuses and contain 5 to 7 lobes that typically have 3 to 4 bristles extending from the tip. In autumn the leaves can turn anywhere from a bronze to a rustic red color.  The bark is fairly smooth and tight, developing small fissures as the tree ages. The pin oak’s acorns are smaller than most other oaks and are topped by a thin cap , and the flowers are small inconspicuous spheres extending from the branches.

Historic uses of the pin oak include examples of the use of its bark in an intestinal remedy concocted by Native Americans and its name is said to have been derived from the early use of its wood as ‘pins’ during the colonial and frontier age that would hold the frames of buildings and structures together.

By far the most important condition affecting the pin oak is the onset of Chlorosis that comes from being improperly planted in soils that are too alkaline for the tree to transport enough iron from its roots to the upper structure of the tree, resulting in sickly white leaves that cannot photosynthesize properly. Otherwise this species has no particular diseases or pests that are not common to other species of oaks.

As the pin oaks are so popular and widely planted, in many cases it takes no more than a walk around the block to find an example of this hard-working and picturesque tree in your neighborhood! Be sure to look for the bristles on the tips of the leaves or the thin caps on the acorns and you have found a magnificent example of Quercus palustris.

View map full screen.

For more about specific tree species, check out our Tree Talk Thursday online chats, which cover a range of topics from tree spotting and care, to species-specific discussions (like American elm and fruit-bearing trees).

Photo credit: wintersoul1.

Contributing Writer: Sebastian O’Connor, Tree Planting intern

The United States has many national emblems, including a national bird and flower, but imagine what it would be like to add a national tree to that list? Well, if Alexander Hamilton had his way, we would have gotten just that: he was very fond of September’s Tree of the Month: the sweetgum (Liquidambar styraciflua).

Mr. Hamilton once said that he wanted to see his favorite tree become “America’s emblematic tree,” and although it is perhaps unfortunate that the sweetgum did not make it into the same exclusive club as the bald eagle and the rose, it remains a popular and prized tree wherever it’s found. Liquidambar styraciflua ranges along most of the eastern United States: from Connecticut to southern Florida, and from the swells of the Atlantic all the way to Oklahoma. It is a member of the Witch-Hazel family and can even be found in areas of Mexico and Central America.

The best way to recognize the sweetgum is by its five-pointed, star-shaped leaves that bear a close similarity to some members of the Maple species. The leaves are alternate and serrated, with a long stem attaching it to the branch and tinted in a rich green color. In the fall the sweetgum really stands out as its leaves turn to a brilliant spectrum of red, yellow, orange, and purple colors. Flowers come in small, inconspicuous round shapes attached in clusters to a thick stalk, but the fruits of Liquidambar styraciflua are easily recognizable due to their round, hard and spiky shape.

The sweetgum is one of the most common hardwoods in the eastern United States and is fairly adaptable to different conditions. It prefers moist, acidic or loamy soils and can tolerate poorly drained and salty soils as well. Liquidambar styraciflua are a long–lived species, and commonly reach ages of over 400 years. It is a medium-to-large-sized deciduous tree that normally doesn’t grow taller than 115 feet with a minimum height of 70 feet.

The sweetgum is prized in the lumber industry as an affordable, durable wood that may not be the strongest but the rich red color of the wood can be polished to create many beautiful pieces of furniture or luxury items. Historical uses of the sweetgum include the harvest of its resin as a cure for sciatica and weak nerves. Interestingly enough, a chemical compound from the related Oriental sweetgum helped to invent Styrofoam. They are also widely used in land reclamation projects as they grow quickly and are insect-resistant.

With its advantages of year-round beauty, longevity, and fragrant wood and leaves it is easy to fall in love with the sweetgum, just like Alexander Hamilton did long ago. We are lucky to see this tree commonly in D.C., and if you want a closer look you need to go no farther than the National Zoo, the U.S. Capitol grounds, Constitution Gardens, or the Vietnam Veterans Memorial, to name but a few.

View map full screen.

For more about specific tree species, check out our Tree Talk Thursday online chats, which cover a range of topics from tree spotting and care, to species-specific discussions (like American elm and fruit-bearing trees).

Photo credit: EphusBailey.

Contributing Writer: Sebastian O’Connor, Tree Planting intern

Do you have a taste for honey, an eye for vibrant colors, and a love for trees with a slightly drooping form? Then Oxydendrum arboretum, also known as the sourwood, may be the perfect tree for you!

The sourwood is a lively and bold tree that ranges along most of the southeastern United States, from North Carolina to Arkansas, and West Virginia to the Gulf of Mexico (although it largely bypasses Florida). A member of the Ericaceae (heath) family, the sourwood is a deciduous and slow growing small-to-medium sized tree. Although special cases can occur where the tree reaches 90 feet in the wild, most of the time you will find cultivated specimens no taller than 40 feet.

A special feature of the sourwood is its leaves, which are arranged in spiral or alternate form with an oblong, oval shape. The edges are finely toothed and the upper surface is shiny and smooth and bright green in the summer. Part of what makes the sourwood distinctive is that the leaves droop slightly from their branches, giving the tree a weeping willow-type aesthetic. In the fall, the leaves put on a magnificent show, expressing colors that include a bright crimson red or purplish burgundy. But if you have an urge to take a bite from one of the leaves, be warned that the sourwood is so named because of the very sour and bitter taste of its leaves!

Also contributing to the sourwood’s beauty are its small and delicate, yet showy white flowers that are very fragrant and shaped like a small bell. In July these wonderful flowers come to full bloom and attract a number of pollinators. The nectar from the flowers are incredibly sweet and contribute to a highly-prized honey, which is one of the main commercial uses of the sourwood tree. Oxydendrum arboretum sprouts fruit in late fall consisting of small, hardened capsules that holds many pale brown wingless seeds.

The sweet nectar and sap of the sourwood led to early colonists and Native Americans utilizing it for a variety of things. It was used as a tonic, decoction, and even as a gum; medicinal uses include treating urinary problems, prostrate conditions, diarrhea, dysentery, and many other symptoms. The Oxydendrum arboretum is a little less adaptable to its environment than other urban trees as it is generally intolerant of heavy shade, as well as high soil alkalinity and salinity. It prefers moist, well drained soils with a balanced pH level that are not compacted. On the other hand, although it attracts some nuisance pests, the sourwood is very easy to care for and has no known major diseases.

Its small size and particular growing requirements mean that you will most likely find the sourwood tucked away in public parks and private residences rather than along streets and walkways. In Washington, D.C. you can find examples of this fine tree near the National Cathedral, the Glenwood and Arlington cemeteries, as well as Walter Reed Army Medical Center!

View map full screen.

For more about specific tree species, check out our Tree Talk Thursday online chats, which cover a range of topics from tree spotting and care, to species-specific discussions (like American elm and fruit-bearing trees).

Photo credit: Mrs. Gemstone.

Contributing Writer: Sebastian O’Connor, Tree Planting intern

For many tree enthusiasts and amateurs, July’s Tree of the Month is possibly the easiest tree to identify and the one most likely to give a nice gash. Gleditsia triacanthos, otherwise known as the honey locust, is native to the central United States and commonly has an arrangement of sharp thorns along its bark to scare away nosy animals and pests, making it feel more like a cactus than a tree!

But don’t be afraid of its anti-social attitude, for the honey locust is a very pretty and useful tree that is commonly planted as an ornamental. Its leaves are delicate and narrow, arranged in an alternating compound form that allows more light to reach the ground and can permit other trees or plants to flourish underneath its canopy. In the fall the leaves can turn to a striking golden yellow. The honey locust is a very fast grower, and commonly reaches heights of around 70 to 100 feet. Unfortunately Gleditsia triacanthos does not normally live as long as other trees and can die as early as 100 years.

The flowers of the honey locust are small and not showy, but the fruits are borne in long slender pods 15 to 40 cm long with sticky and sweet bean-like seeds. Expect flowering to happen May through June and for fruit to appear in September and October. Although the honey locust does not help to make honey, the name was given to the sweet taste of the seeds themselves, which were often eaten by Native Americans. They were also used as a coffee substitute and can even be fermented. Needless to say, they are very popular with the local wildlife as well!

It is possible to see many honey locusts in Washington D.C. because the species is highly adaptable and can grow well in urban conditions. Although they prefer moist and well-drained conditions, they are also drought resistant and tolerate a good amount of salinity. This means that they are well suited to D.C.’s marshy and humid environment and can tolerate the frequent use of road salt as well as adapting to the compact soil found along roads and sidewalks.

Likewise, the honey locust is generally free from diseases and pests except for the mimosa webworm defoliator and the canker fungus. So when thinking about a great tree, think about the ease of maintenance, the unique look (as long as you are careful!), and the versatility and adaptability of Gleditsia Triacanthos as you think about planting your next tree. In D.C., the honey locust is commonly planted but look to the National Gallery of Art grounds, 1st Street SE near Independence Avenue, and at the intersection of C Street and Sixth Street, NE for the best chance to check this tree out for yourself!

To find out other places where they grow, check out our interactive tree map. Red dots signify trees planted by the city.

Photo credits: sloanpix on Flickr and ZeNeeceC on Flickr

Contributing Writer: Sebastian O’Connor, Tree Planting intern

Carya glabra, also known as the pignut hickory, is June’s Tree of the Month and shares a name with a famous U.S. politician. That’s right, the seventh president of the United States, Andrew Jackson, was also known as “Old Hickory” due to his battle-hardened character. Andrew Jackson was a major general in the army during the War of 1812 when he rallied troops to defend New Orleans and decisively defeat the British forces, setting him on a path to the presidency and earning his reputation as a strict leader and aggressive foe.

Like President Jackson, the pignut hickory is tough and resilient and — unlike Jackson — often grows to a stately size of between 80 and 120 feet. Its range of native growth covers most of the eastern U.S., reaching into Florida in the south and Vermont/New Hampshire in the north while struggling to get past Missouri to the west. Hickories can grow in a variety of soil conditions but are most frequently seen growing on dry ridge tops or on the slopes of mountains, especially along the Appalachians.

Perhaps the most distinctive aspect of the pignut hickory is its nut, which is pear-shaped and has an inner structure similar to a pig’s snout when cut in half. Pignut hickories are prolific nut producers, which help them expand and saturate a forest or grove quickly. Carya glabra also generates a fine source of nutrients for local wildlife, as its nuts contain a high amount of crude fat that is especially useful for animals stocking up for winter hibernation. The leaves are alternating, compound leaves that contain 5 to 7 leaflets that are slightly serrated, but smooth and with a rich green color on top. In the fall the leaves turn to a pale yellow or light orange color.

Andrew Jackson’s earned the nickname of Old Hickory because the hickory species was prized for its wood, which was extremely durable, stiff, and shock resistant. This permitted it to be used in everything from tool handles to stagecoach wheels, to baseball bats and Native American bows. It was also used extensively as firewood because of its density and today is used for smoking meat.

Carya glabra is a monoecious species, meaning that both male and female flowers are located on the same tree, and it can live to a ripe age of over 300 years old. Pignut hickories are generally tolerant of pests but can be severely damaged by a trunk rot caused by Poria spiculosa, which is common to many pignut hickories and results in large burls protruding from the trunk, degrading the tree’s growth and adaptability.

In Washington, D.C. the pignut hickory can be found primarily in Rock Creek Park, and although it is not as widely planted as other trees, they can be found in many parks, sidewalks, and other public places.