Eastern redbud, Cercis canadensis, is also known as redbud or Judas tree. The name “Judas tree” is derived from the legend in which Judas Iscariot, one of the twelve disciples of Jesus Christ, hung himself from a branch of Cercis siliquastrum, an Asian and European species of the genus. Cercis siliquastrum is the species more likely to be called Judas tree.

Young eastern redbuds grow quickly, sometimes flowering before 7 years of age, with the first seeds appearing a year later. Eastern redbuds on average grow 15 to 30 feet tall, with a 15 to 25 foot spread.

As with most trees that have such a large distribution area, Eastern redbud can survive in many climatic conditions. Frost free days number 160 to 300 days. It can be found on dry or moist soils but does prefer moist, well-drained areas and cannot tolerate flooding. It is most commonly found on south-facing slopes where it can get more sunlight. Eastern redbud can grow in almost all soils, save coarse sands. Additionally, it does best when pH is above 7.5, though it is tolerant of lower values. It is also tolerant of nutrient deficient soils.

The flowers of Eastern redbud appear earlier than most other trees sprout flowers or leaves, from March to May, making it distinctive. Flowers are pink to reddish purple, and occasionally white. All flowers are bisexual and grow in clusters of two to eight. Fruits are flat pods 2 to 4 inches long with 4 to 10 seeds in each.

Eastern redbud becomes less tolerant of shade as it ages. Old trees also suffer from heart rot. Insect damage, while common, is not severe. It is also fire tolerant compared to other species.

In addition to butterflies, honeybees, deer, squirrels, hummingbirds, and other birds utilize or eat various parts of the tree, such as nectar, pollen, leaves, twigs, bark, seeds, fruits, and buds. Native Americans boiled the bark to make a tea that treated whooping cough, and the bark could be used to treat dysentery. Bark and roots were used for fevers, congestion, and vomiting, as well. Humans also fry and eat the flowers, or put them into salads.

Cornus, Tree Species

Cornus florida

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Flowering dogwood, Cornus florida, is often also known as dogwood, boxwood, and cornel. However, the “flowers” of this dogwood are not actually flowers, but petal-like bracts, making it a misnomer.

Flowering dogwood is found in Mexico, the United States, and Canada.

The growing season lasts from 160 days to 300 in Florida. Flowering dogwood grows up to 55 feet in height with 19 inches of trunk diameter. Flowering dogwoods can live 125 years.

Well-drained soil is important, particularly for young flowering dogwoods, though older trees can survive on less well-drained soils. Flowering dogwood prefers moist soils with a pH of 6 to 7. Flowering dogwood also does not do very well on upper slopes, though it does well on middle and lower slopes, as well as flat land.

Leaf litter decomposes rapidly compared to other trees and is considered a soil improver. It adds calcium to the soil, as well as potassium, phosphorus, magnesium, and sulfur.

The true flowers are small and yellowish, forming in clusters. The “flowers” made of bracts are much more prominent, with four white, pink, or red “petals”. Fruits are clustered red drupes that are half an inch long. Each drupe has a stone with one or two seeds. The fruits ripen from September to late October. Good seed crops happen every two years.

The very shallow roots are likely the reason flowering dogwood is susceptible to drought, and the thin bark makes it susceptible to fire. However, flowering dogwood is very tolerant of shade.

The leaves, seeds, fruit, flowers, twigs, and bark are all eaten by wildlife. It is also often used as an ornamental tree.

Fagus, Tree Species

Fagus grandifolia

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American beech, Fagus grandifolia, is the only species of Fagus natively present in North America. It is believed that American beech had a much greater extent before the last glaciation period, even reaching to California.

Some of the largest examples of American beech can be found in the Ohio and Mississippi River Valleys, and in good conditions they reach 120 feet in height. American beeches are capable of living at high elevations, but tend to only do so when the average temperatures are warmer. In colder regions, it tends to be found at lower elevations.

Old trees can reach between 300 and 400 years.

While American beeches are not found in areas with particularly high precipitation, they do require twice as much water for growth than other drought resistant trees, such as some oaks. Growing season varies from 90 to 280 days.

American beeches are monoecious and flower in April or May. The flowers are very vulnerable to spring frosts. Beechnuts ripen a year later between September and November, with large quantities starting once the tree is 40 years of age. Typically each fruit holds two nuts.

American beech is very tolerant of shade and sensitive to flooding and fire. A record large number of fungi can attack American beech, as well as numerous insects.

Mice, squirrels, chipmunks, bears, deer, foxes, and birds can all feed upon parts of the American beech. Beechnuts are not only eaten by wildlife but also by humans.

Fraxinus, Tree Species

Fraxinus americana

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White ash, Fraxinus americana, is also known as Biltmore ash and Biltmore white ash. It is likely the most commonly cultivated ash in the United States, though is not dominant in nature. It is, however, a pioneer species that is capable of establishing itself early on abandoned fields.

White ash is considered a medium sized tree. It can take 3 to 15 years to reach 5 feet of height. White ash has been known to reach at least 80 to 90 feet with 15 to 20 inches in trunk diameter. White ash is capable of surviving at various elevations. It is frequently found on slopes.

The distribution is wide enough to allow the climate to vary greatly. White ash grows best on moist, well-drained soils. Moisture is important. Flooding, however, is only intermediately tolerated. It also requires good soil fertility, though this is offered by numerous soil types. The best soils have abundant nitrogen and calcium. Sulfur is also desirable.

The first flowering occurs when the trunk diameter is 3 to 4 inches wide, but becomes more abundant once the trunk reaches 8 to 10 inches. The tree is dioecious, meaning there are separate male and female trees. The flowers tend to appear in April or May, either before or simultaneously with the leaves. Most fruits contain one seed each, and the trees bear seeds beginning at 20 years old. While the seeds are considered mature between September to December, they are not capable of germinating until they have been buried in moist soil for 2 or 3 months. A good seed crop is produced every three years.

White ash is shade tolerant when young, though less tolerant as it grows older. Ash dieback is a severe issue for the white ash, with the disease causing death and weakness. White ash is very sensitive to air pollution, specifically ozone and sulfur dioxide. Other diseases and insects are also harmful to white ash.

White ash was used as a snake bite preventive, effectively or not. Squirrels and birds also feed upon the seeds.

Gleditsia, Tree Species

Gleditsia triacanthos

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Honeylocust, Gleditsia triacanthos, is typically also known as sweet locust and thorny locust. The variety found at Lafayette is Gleditsia triacanthos var. inermis ‘Shademaster’. The var. inermis makes it thornless, so it can also be referred to as the thornless honeylocust. The ‘Shademaster’ cultivar is a cultivar for this variety, and the resulting common name is the shademaster honeylocust.

A key for honeylocust cultivation is a temperate climate. Its native range boasts subhumid to humid climates, and growing seasons reach from 150 to over 300 days. Typically, the honeylocust is tolerant of low temperatures. However, some varieties are less tolerant of others, so they may be damaged by frost.

The honeylocust does best on limestone soils or on floodplains and prefers moist soils. However, it is still very resistant to drought. It is also very tolerant of alkali and acidic soils, even if the prime pH range is typically between 6 and 8. Best growth is also below 2,500 feet in elevation. Above 5,000 feet, growth is still possible, but trees only average 8 feet in height. Without this elevation issue, honeylocusts typically grow to 70 or 80 feet with a 24 to 36 inch diameter trunk. The largest trees reach beyond 140 feet in height with 60 to 72 inches in trunk diameter.

Flowering occurs between May and June, when the leaves are already out. As honeylocust is polygamodioecious, it has bisexual and male flowers on some trees and bisexual and female flowers on others. Flowers tend to be white to a light greenish yellow and grow in clusters, on drooping columns. Honeylocusts produce seeds starting at 10 years of age, with maximum production between 25 and 75 years of age, continuing until age 100. Seed pods ripen between September and October. The pods are 6 to 16 inches long and flat.

Root cuttings are potentially the best method for propagation, though cuttings of other portions of the plant are typically successful.

Honeylocust is shade intolerant at all ages. While there are an increasing number of insect pests, most are not fatal. Likewise, several diseases affect honeylocust, but none tend to cause devastating injury to the tree. It is resistant to salt spray, wind, and flooding, but is susceptible to fire damage and air pollution damage.

The widest dissemination of seeds is caused by cattle and other animals feeding and then dispersal through feces. In fact, digestion is thought to be very helpful to the germination of seeds. The fruits and beans are eaten by cattle, hogs, squirrels, deer, birds, and opossums. Additionally, honeylocusts are often used for erosion control and have been used to replace American elms that have been killed by Dutch elm disease.

Gymnocladus, Tree Species

Gymnocladus dioicus

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Kentucky coffeetree, Gymnocladus dioicus, is also known as American coffee bean, American coffee berry, American mahogany, bean tree, chico du Canada, chicot, chicot tree, coffeebean, coffeebean-tree, coffeenut, coffeetree, dead tree, geweihbaum, Kentucky coffee-tree, Kentucky mahogany, mahogany, mahogany-bean, nettle-tree, nicker tree, nicker treet, and stump tree. The “coffee” in the common name is derived from usage by settlers. The toasted beans were used as substitutes for the less available coffee. “Dead tree” and “stump tree” are derived from the tree’s habit to go dormant for 6 months of the year. It is the only member of Gymnocladus native to North America.

Overharvesting of the tree has greatly reduced its numbers, and it is considered endangered in New York. Dissemination of trees is only done through water, as squirrels do not utilize the seeds, making it harder for the tree to spread. Even in its native habitat, Kentucky coffeetree is uncommon.

Kentucky coffeetree can grow to 100 feet with a 50 foot spread. Particularly tall specimens have reached 130 feet. Young specimens grow fast, though growth slows greatly with age.

The leaves are alternate compound leaves which can measure 1 to 3 feet in length, usually with 6 to 14 leaflets. Leaves emerge pink-bronze in the spring, turning dark bluish-green in the summer before becoming golden yellow in the fall. The flowers are largely inconspicuous, and are greenish-white and small. They appear in May and June, after the leaves. The fruit is a legume that matures in September or October. The seeds are incredibly hard, reputably 2,000 times harder than a jawbreaker.

Kentucky coffeetree prefers moist soils and full sun, and is usually found in previously glaciated areas. It can tolerate drought and flooding to an extent.

The leaves and raw seeds of Kentucky coffeetree are poisonous to humans and animals. In addition to settler’s usage of the seeds as coffee substitutes, the leaves have been used as fly poison and the fruit can be used as soap. Native Americans used the pulp to treat insanity, fever, and headaches, and thus dispersed the tree further throughout North America. The bark was used as an appetizer and tonic, the toasted seeds as food, and the pulp and leaves were used to create a laxative tea. The raw seeds could also be used to kill fish. While the tree has been cultivates as an ornamental tree since before 1748, it is rarely found as such.

Do not eat this tree.

Ilex, Tree Species

Ilex Opaca

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The American holly, Ilex opaca, is also known as white holly or Christmas holly. The name “Christmas holly” comes from the notable used for Christmas decorations, which started when pilgrims in 1620 noted its similarities to the English holly back home, also used for Christmas decorations. The distribution of the American holly is similar to that of the loblolly and shortleaf pines combined.

Typically, hollies are found as scattered trees and not in groups or stands.

American holly can grow 3 to 4 feet per year under prime conditions. Older American hollies can grow up to 50 feet, though most American hollies are between 15 and 30 feet. The tallest individuals are 100 feet tall, with almost 50 inches in trunk diameter. Over 100 years is considered old for an American holly, though they have been known to reach 140 years.

American holly prefers humid climate conditions. Growing season can vary from 150 days further north to year round in Florida. It prefers the relative warmth of southern states but can survive average low temperatures of -20° F. It is recognized as the hardiest broadleaf evergreen tree.

American holly tolerates even very nutrient poor soils, but prefers moist, slightly acidic, well-drained sites. It cannot tolerate large periods of flooding. American holly is shade tolerant, although growth is reduced under shade. Shade allows for greener leaves.

American holly is dioecious, as hollies tend to be, meaning there are separate male and female trees. Flowering can begin anywhere between 3 and 9 years of age, with flowers appearing from April to June. The flowers have four to six small white petals and appear on both the male and female trees. Pollination is done by insects.

The fruit is commonly called a berry, though it is not technically a berry. The fruit is usually red but can be orange or yellow. Each fruit has four seeds. The fruit matures from September to December.

Hollies are easily transplanted. Trunks typically sprout, and cuttings from the wood can be successfully grown, though root cuttings are not ideal.

The largest danger to American holly is the harvesting of branches with berries for Christmas decorating. This is often done by casual persons to wild American hollies, in ways that often resulted in the death of the tree. Additionally, fire is a large danger, which may be the cause of hollies being found predominantly as individuals.

American holly fruit is eaten by birds and mammals. Leaves are also eaten by mammals. American holly is not poisonous. While not typically recognized as a honey tree, it does produce good honey.

Liquidambar, Tree Species

Liquidambar styraciflua

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Sweet gum, Liquidambar styraciflua, is also known as sweetgum, redgum, sapgum, starleaf-gum, and bilsted.

Sweet gum is not restricted to the United States, and can be found natively in Mexico, Guatemala, Belize, Salvador, Honduras, and Nicaragua as well. Due to this, is has sizable variation in climate conditions.

Sweet gum is very tolerant of different soils and conditions, making it one of the most adaptable hardwoods. Sweet gum can be found on many soils at many elevations as a dominant tree compared to its neighbors. It does, however, do best with moist alluvial clays and loamy soils near rivers.

As a monoecious tree, an individual tree hosts both male and female parts. Flowers are small and green, and easily damaged by frost. Seed production begins between 20 and 30 years of age and can continue for at least 120 years. Seeds are produced in balls that can have between 5 and 56 viable seeds, depending on climate conditions.

Sweet gums are intolerant of shade. While many trees are more delicate at a young age, sweet gums are able to withstand conditions as young trees that become increasingly insufferable as the tree gets older.

While diseases are not particularly dangerous to sweet gums, animal grazing and fires are very damaging.

Liriodendron, Tree Species

Liriodendron tulipifera

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Tulip poplar, Liriodendron tulipifera, is also known as yellow poplar, tuliptree, white poplar, and whitewood. This tree has a tall, straight trunk with no lateral branches beneath a certain height, and is taller than any other Eastern United States broadleaf tree. It can grow up to 200 feet in height with an 8 to 12 foot diameter trunk. The tree often lives 200 to 250 years, but can survive to 300 years.

While its distribution stretches across the Eastern United States, the tallest tulip poplars and most abundant groves are found in the valley of the Ohio River as well as on mountain slopes.

Because its distribution is so expansive, tulip poplars have been known to face a wide variety of climates, from harsh winters to mild, almost entirely frost-free winters. The average number of frost-free days reflects this, ranging from 150 to 310 days.

A notable impact of preferred climates and conditions is the local topography in which the tree is found. Further north it prefers lower elevations of under 1,000 feet when compared to its typical appearances in the southern Appalachians, where it is more abundant on higher slopes. Further south, where temperatures are highest, it prefers moist, low elevations near streams.

Overall, the tree appreciates moist, well-drained soils and does best when rainfall is distributed evenly throughout the growing season. The tulip poplar prefers loose textures soils and does well on alluvium, talus slopes, and gravelly soils. While there have been some correlations between chemical properties of the soil and growth, tulip poplars are much more depended on physical properties. The trees prefer lower slopes or sheltered coves. The best slopes are concave with a lower gradient and a north or east aspect.

Tulip poplarshave distinctive flowers, which bud as individuals along the branch. Each flower is 1.5 to 2 inches wide with six petals. The center of the flower is greenish yellow, and the petals are each a similar greenish yellow with an orange band running horizontally through the center. Flowers first appear when the poplar is 15 to 20 years of age, and will appear annually for a further 200 years, between April and June, lasting for two to six weeks. While insects often pollinate, self-pollination also occurs. Seeds then fall from mid-October to mid-March. Tulip poplar produces a large number of seeds, which are produced in cones with perhaps an average of 8 to 10 viable seeds per cone. Seeds are larger in the southern portions of the distribution area.

Though shade intolerant, tulip poplars grow fast and produce large amounts of seeds, letting them dominate areas easily. It is also remarkably unaffected by insects.

The tulip poplar is often used commercially for its versatility and is a good source of food for wildlife. It is also an excellent honey tree, capable of producing 8 pounds of nectar (4 pounds of honey) per season even below the age of 20.

Magnolia, Tree Species

Magnolia acuminata

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Cucumber magnolia, Magnolia acuminata, is also known as cucumbertree, yellow cucumbertree, yellow-flower magnolia, and mountain magnolia. Cucumber magnolias were thus named due to the cucumber-like fruit, which ripens in late August to September.

Of the magnolia trees native to the United States, cucumber magnolias are the most widespread and hardiest. They are the only magnolia native to Canada. Even though these trees are widespread, they are not abundant over their distribution area.

The biggest cucumber magnolias are found in the mixed hardwood forests of the southern Appalachian Mountains. Cucumber magnolias prefers cool, moist soils in mountainous terrain, with humid to subhumid climates. Growing seasons last between 110 and 260 days, with 150 to 230 frost-free days. Cucumber magnolias can survive brief extremes in temperature.

Cucumber magnolia flowers can be found from early April to early June, after the leaves begin development. At night, the flowers close, but still only last 2 to 4 days. Self-pollination is rare, as even though the tree produces both male and female parts, pollen is not ripe until after the individual tree’s female part is not receptive. Most pollination is then carried out by insects. Each “cucumber” fruit makes 10 to 60 seeds, with good crops appearing every 4 to 5 years.

The short period of pollen shedding and receptivity as well as the delicate nature of the flower may adversely affect the reproduction of cucumber magnolias. Additionally, the seeds are especially sensitive to temperature and moisture, to an extent that may outrival any other tree seed.

Cucumber magnolia can reach a height of 100 feet with a trunk diameter of 36 to 48 inches. Cucumber magnolias are considered mature by 100 years and rarely survives beyond 150 years. That means rapid growth.

While there are no diseases that particularly affect the cucumber magnolia, it is sensitive to fires and frost. It does have an intermediate shade tolerance.

Campus Tree Project

Campus Trees

Cercis canadensis

Cornus florida

Fagus grandifolia

Fraxinus americana

Gleditsia triacanthos

Gymnocladus dioicus

Ilex Opaca

Liquidambar styraciflua

Liriodendron tulipifera

Magnolia acuminata

A look at the trees on the Lafayette College campus