What Tree Where

Bristlecone Pine–Cursed Tree or one That Changed History?

They are slow growers and may add as little as one 1/100 an inch of girth in a year

There are two species of bristlecone pine, both native to the southwestern United States. Pinus aristata, known as the Rocky Mountain bristlecone, hickory pine, or Colorado bristlecone, grows in the mountains of Colorado, New Mexico, and Arizona.

Pinus longaeva, native to Utah, Nevada, and California, is called either Great Basin bristlecone or Intermountain bristlecone. Both species are long-lived, but the Intermountain Bristlecone holds the record as possibly the oldest living specimen on earth. At first glance the name bristlecone seems to be due to the small branches with their short, stiff leaves which cause them to look a bit like bottle brushes. A third moniker for the Colorado Bristlecone is foxtail pine due to branches resembling those of foxes.

Close up of a branch — Small branches looking somewhat like a bottle brush

Originally both species were classified as foxtail pines (Pinus balfouriana) but were reclassified in the 1800s and the two types of bristlecone were further distinguished in the the 1960s. The actual reason longaeva and aristata are called bristlecone pines is due to a bristle on the young cone.

Both species belong to the five-needled or white pine group of Pinus. In Colorado, bristlecones typically grow from an altitude of 8300 to 13000 feet (Ackerfield.**) At higher altitudes they are slow growers. According to one source they may add as little as 1/100th of girth in a year. Often bristlecones grow with both limber pines and Engelmann spruce and sometimes near treeline with common juniper. Their seeds are tiny. Unlike most other pine species, they are winged. The trees do not produce seeds until they are between ten and forty years old, but may continue to reproduce throughout their extremely long lives. Most references mention these evergreens retain their needles for many years, with one article stating the needles may persist for decades. Often the needles are sprinkled with white resin spots, making the tree look like it has suffered a case of dandruff.

Bristlecone closeup — Close up of a branchlet of a bristlecone pine

When discussing edibility or medicinal use of the bristlecone, sources such as Edible & Medicinal Plants of the Rockies (Kershaw, Linda, 2000) and Medicinal Plants of the Mountain West (Moore, Michael, 2003) tend to lump them in with other five-needled pines. Both sources mention pine needle teas to enjoy or use for coughs and fevers. Both sources warn an excess of the tea may be detrimental, especially to pregnant women. Pines may also provide resin and be used for firewood, although in national parks, all bristlecone pines are protected.

Dirr and Warren* mention the bristlecone for the landscape, especially in dry areas with poor soil. They do need full sun and are usually sold as cultivars. In the yard they may have the look of whimsical holiday trees. At higher altitudes they have the appearance of large pieces of misplaced driftwood.

Although Pinus aristata has evolved numerous survival mechanisms, and the ability to adapt to hardships may be part of the secret to its longevity, climate change may be playing a part in new dangers to these old trees. In the early 2000s, bristlecone pines were documented to have died from mountain pine beetle infestations. White pine blister rust and dwarf mistletoe are also known to endanger these long-lived trees.

A Pinus longaeva specimen known as Prometheus was counted as nearing 4900 years when it was cut down by graduate student Don Currey. There are various stories about how exactly this tree was destroyed with the exact facts in dispute. A full reckonning of the acrimony and confusion surrounding the Great Basin bristlecone pine designated as WPN-114 has many facets of today’s fights about climate change. To make the death of this tree a greater tragedy, when the pith of the tree was sent to the University of Arizona’s Laboratory of Tree Ring Research after Don Currey’s death, a more precise dating of the tree was determined. Now some estimate Prometheus may have been 5100 years old.

In a piece developed for Radiolab, the hosts play a recording of Don Currey telling part of the story of WPN-114’s demise. The piece on Prometheus begins around 15:00 minutes. Although interesting, there appears to be at least one mistake in the update. Prometheus lived in the Snake Mountains in what is now Great Basin National Park, while the White Mountains and the disputed new oldest tree is in California.

In 2014 the artist Jeff Weiss produced an exhibit, or as he calls it “a thing,” to mark the 50th anniversary of the cutting down of this great tree. (There is a film about this “thing” discussing the history of the tree and the art; the story starts around 9:48. Although the information is overall interesting, there are a lot of extraneous comments.)

Another Pinus longaeva, Methuselah, is a mere fifty years younger and still living. And a third, even older tree is rumored to have been located by the same man (Edmund Shulman) who found Methuselah, but this has not been verified. The tree is said to be living in an undisclosed area of the White Mountains and was 5067 years old in 2019. The oldest Rocky Mountain bristlecone, which is located in Colorado, is a mere 2436 (in 2020) years of age.

According to the Gymnosperm Database, the largest specimen of Pinus aristata is located in New Mexico. The tree may be of dwarf stature at high elevations but may reach 40′ at lower altitudes. The 2018 champion tree in Colorado was found in the San Isabel forest and reached a height of 59′, about twenty feet higher than the next candidate. Lower altitude trees may not reach the great ages of their counterparts closer to treelike. They may become victims of heart-rot, decreasing their longevity to around 300 years.

Bristlecone bark — Bark of the Rocky Mountain Bristlecone Pine

The Rocky Mountain bristlecone’s relative, the Great Basin bristlecone pine has also played a part in calibrating carbon dating techniques and helped correct the historical record. This was done by overlapping tree ring patterns from living tree core samples and intact patterns of deadwood. This technique has enabled dendrochronologists, archeologists, and historians to examine climatic and other patterns over 10,000 years and has earned the Intermountain bristlecone pine the moniker the Tree that Rewrote History. Here is a link to a 2009 poetic documentary, The Oldest Tree on Earth: The Curse of the Methuselah Tree. It includes a clip of Don Currey discussing the cutting of Prometheus and information from the person who claims to have found an even older specimen.

The curse of the bristlecones implies those who touch/cut the trees will have brief lives. Edmund Shulman who cored Methuselah in the 1950s died at 49, while a 32-year-old Forest Service employ who helped carry a slab of Prometheus off the mountain suffered a heart attack on the way down and died. Currey, who one would assume would be the most cursed, died at 70, diminishing the likelihood of a curse in my mind. A highly recommended 2020 New Yorker article by Alex Ross, “The Past and Future of the Earth’s Oldest Trees,” discusses the curse, dendrochronology, the controversy over the bristlecone’s possible submission to climate change, and other aspects of this species.

bristlecone against the sky — Colorado Bristlecone pine hiding amongst the spruces.

To find C170 Pinus aristata in City Park, go to the intersection of Mulberry Street and Sheldon Drive. On the northeast corner is a small grove of trees including some spruce and deciduous trees. The shortest of the conifers should be the Colorado Bristlecone pine. Last I looked, I did not see its tag. This tree was planted in 1978 when it had a diameter of eight inches.

*The Tree Book:Superior Selections for Landscapes, Streetscapes, and Gardens (Dirr, Michael and Warren, Keith, 2019)

**Flora of Colorado (Ackerfield, Jennifer, 2015)

By the Beech

An unusual use of the buds in the spring is as a toothpick.

When interviewing Molly T. Roche, Senior Forestry Coordinator for the City of Fort Collins, back in 2018, I suggested we take her photo near one of her favorite trees. She selected the European Beech. We took the photo that summer, but I was hoping to include another when its leaves had turned. A cold spell and snow ensured the leaves on most trees crinkled up and turned brown. I waited through this fall but once again, didn’t get a photo.

Molly by the Beech — Molly by the beech, summer 2018.

Although there is an American Beech (Fagus grandifolia) which is native to the East and Utah, the tagged tree in City Park is a European Beech (Fagus sylvatica.) This species has been introduced to North America and similar to the native Fagus, grows in the east and Utah. Beeches belong to the Beech, or Fagaceae family, which includes the oaks, chestnuts, chinquapins, and two other genera that grow mostly in Asia.

The young leaves of the European beech are edible. Some say they have Sunlight through the beech leaves a taste somewhat like sorrel, which if you’ve never eaten it, has a lemony flavor. The leaves can be steeped in gin to create an alcoholic drink or made into a tea. And although this is NOT mentioned often, at least one company in the US makes a syrup Beech syrup from the American beech (Fagus grandifolia) sap. Granted this is not the same type of beech as in the park, but it is still interesting. A study done in Maine has cited a change in Northern forests from maples to beeches due to climate warming. Possibly a switch to Beech syrup can help save some of the current maple sugaring jobs.

Beech seeds, also known as beech nuts, according to most sources are quite tasty, although they may take a bit of work to prepare. Some may roast and grind seeds as a coffee substitute. Although a few seeds may be produced by the time the tree is 10 years old, trees do not fully produce nuts until they are 40 to 80 years old. An unusual use of dried beech buds is as toothpicks in the winter!

According to Monumental Trees, the beech tree trunk with the most girth, over 28′, can be found in Germany as can the tallest (>161 feet). According to the Sibley Guide to Trees (Sibley, 2009), a more usual height for a tree planted in North America is 50-70 feet. The internet site lists the oldest known Fagus sylvatica as a tree in Italy of 520 years. A “tree” planted around 1850 in Massachusetts is listed as the oldest known European beech in the US.

Sources vary on how useful the wood of a beech is for woodworkers. Most mention some furniture making as well as use in parts of instruments such as drums. Beeches in Europe have been used to construct cabins and furniture. Logs are used as firewood. They split easily and burn well. They may also be turned into charcoal or used to manufacture creosote.

The verdict seems to be out on using beech wood or chips for smoking foods. Most lists on the internet leave it off. One says it is long burning but has a strong flavor. Another says it is mild, similar to apple or pecan. This last mentions it is popular in Germany and used to smoke dishes such as Nuremburg bratwurst.

Beech trunk — The gnarly, elephant look of the beech trunk

There is controversy about the medicinal use of the beech, too. Although many sites mention some uses for its oil, leaves, and bark, most warn about toxicity or difficulty in procuring enough seeds or oil to be of much use. Other sources suggest even the bark may be ingested to improve digestion, and decoctions of seeds have been used to improve kidney function. Poultices made of the leaves have been used for headache relief and a tar made from the beech may be considered an antiseptic and has been applied for toothache relief.

A bestseller written in 2015, The Hidden Life of Trees: What they Feel, How they Communicate–Discoveries of a Secret World by Peter Wohlleben, which has received many good reviews, talks about the life of various trees but features beeches. The book isn’t without controversy, though, as seen in this article from The Guardian. The book almost reads like a novel but is backed up with scientific studies. It will certainly change how you look and think about trees.

To find Fagus sylvatica, go to the section of the park bordered by Oak Street, Roosevelt and City Park Drive. The tree is somewhat in the center of the corner of Oak and Roosevelt. Currently it also sports a bright green box that might look something like a birdhouse but is actually a trap for some sort of bug. A second tagged beech in the park may be found along the lot line with the golf course.

Fully leafed out beech

Beech in early spring

According to The Tree Book ( Dirr and Warren, 2019,) the first cultivar of a European Beech was developed in 1770. Fagus sylvatica, Dawyck Purple is of the fastigate type and according to Dirr and Warren may grow to a height of 40-50′ (p.353.) This specimen has lovely, purplish-red leaves.

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Fagus sylvatica Dawyck Purple

The Purple European Beech may be viewed along Jackson Ave, almost across from the intersection of West Olive Street.

Arizona Cypress: Drought Tolerant or a Fine Specimen Christmas Tree?

Its retained cones look like jingle bells

P3120017 — An opened cone with another closed

Continue reading “Arizona Cypress: Drought Tolerant or a Fine Specimen Christmas Tree?”

A Rare Evergreen with a lot of Names: the Modoc Cypress

Modoc Cypress is listed as Vulnerable.

Modoc cypress does not have a widespread natural range and is found naturally only in northern California and southern Oregon. At least one source calls this species the northernmost and hardiest of its genus, but its need for sunlight and susceptibility to fire seem to contradict the hardiness designation.

In 1898 this species was discovered in Modoc County, California by the botanist Milo Samuel Baker, an important collector and teacher during the early years of the last century. Not only is this tree known as Baker Cypress, Modoc Cypress, or Siskiyou Cypress but there appears to be controversy as to its scientific name. Proposed Latin names are Callitropsis bakeri, Hesperocyparis bakeri, Cupressus macnabiana, or Neocupressus bakeri. The second name is currently used in the USDA plants database. The nomenclature used on the tree tour map and often on the web, is a fifth destination, Cupresses bakeri, one of the older names given in the Gymnosperm Database.

Modoc Cypress is listed in Threatened Conifers of the World and on the Red List as Vulnerable. This may have to do with fire suppression practices as the cones do not normally open to spread seed unless subjected to heat, but the tree can be susceptible to fire damage. The thin, curling bark of the younger trees may also be detrimental in a forest fire. OLYMPUS DIGITAL CAMERA The reproduction cycle of this species is discussed on the above site. When the small, hard cones open, the seed is distributed by wind or rain.

Modoc detail — Cone and leaves of the Modoc Cypress

The tree may grow to fifty feet, but as one nursery website put it, “not in your lifetime, maybe your kids or grand kids.” No tree of this species is listed in Champion Trees, but the Gymnosperm Database lists a specimen in Oregon at 127′ as being the biggest known.

Although there is some information about the medicinal use of cypress, it is also classified as a neurotoxin and is often associated with death. The same website mentions some species are planted in church yards and cemeteries. In the correct dosage some species of cypress may have medicinal and cosmetic properties, but no specific mention is made of the Modoc Cypress.

In City Park Modoc Cypress (D197) may be found near the frog sculptures, closer to Sheldon Drive. To me the cypresses can be identified by a hazy aura around them, probably an illusion from their interesting leaves.

Leaves of the Modoc cypress

Closer view of the leaves

Chinkapin oak, including the Story Behind its Latin Name

The Latin name for this tree features a misspelling.

Once again, like many other species of oak, the chinkapin oak is native to most of the United States east of Colorado as well as in two states sharing a border with the Centennial state, New Mexico and Oklahoma. This species, Quercus muehlenbergii, is also known as chestnut oak, yellow oak, common chinquapin oak, rock oak, rock chestnut oak, and yellow chestnut oak. It is one of those oaks whose leaves the uninitiated might not consider to be oak leaves. Instead, with their ragged or sawtooth-like edges, they could be mistaken for elm or chestnut leaves .

The acorns of this species of white oak are considered of the best eating quality. They are an important food for a variety of birds including woodpeckers and turkeys, as well as black bears and many small mammals and deer. The Chinkapin oak could be considered instrumental in the mobility of this country as the logs were once used as fuel in steamships. Later, logs were used as railroad ties. The wood is often fashioned into cabinets and furniture. The tree also has a few medicinal uses as an antiemetic and astringent.

In the wild the trees grow to 60-80′. Cultivated, they may only reach about fifty feet. The current champion tree in the U.S. grows in Virginia. It stands 66′ tall with a crown spread of 113′. The four trees listed as Colorado champions, all of which are in Denver, range from 62 to 66 feet in height but the largest tree has an overall point value (height plus crown spread plus trunk circumference) of less than half that of the national champion.The oldest recorded tree in the US is around 343 years old and can be found in Springfield, Ohio.

Where did this species get its common name? It bears a similarity to a tree in the same family (Beech) but a different genus and species, Castanea pumila, which has an overlapping range with the oak species. The Allegheny chinkapin, also called a drawf chestnut, is a small tree or shrub with a single burr containing a nut. The leaves of this species look very similar to those of the Chinkapin oak, but the lack of an acorn should be a distinguishing feature.

The American Gotthilf Henry Ernst Muhlenberg (1753-1815) is credited with describing this variety of oak along with the German botanist, Carl Ludwig Willdenow. Muhlenberg was an ordained minister, college president, and botanist who published at least two influential books. A genus of grasses, Muhlenburgia, was named after him. He also discovered a turtle, which was called the Muhlenberg’s tortoise until the name was changed in 1956 to the bog turtle.

The Latin name of the chinkapin oak has a convoluted history, complete with a misspelling. In the past this species was considered to contain three varieties of trees, but on reclassifying and renaming, the species was given the Latin name Quercus muehlenbergii by George Engelmann, which would account for the full name Quercus muehlenbergii Engelm.

And the misspelling? When Engelmann honored Muhlenberg, he used the German spelling with an umlaut, which when transcribed resulted in the muehlenbergii spelling. Both spellings are now sometimes used.

There are two chinkapin oaks identified on the Fort Collins City Park Tree Tour. One is located in the quadrant bordered by Jackson and W. Mulberry. This specimen (C159) is in a group of trees and may have lost its identifying tag. The second tree (E16), located behind the fire station in the southwest corner of the park, was planted in 1996. It also appears to have lost its tag. The tree can be found on the peninsula between the parking lot and the roadway, near a fake rock.

Bur Oak: largest native acorns

In Texas the acorns may be the size of golf balls!

While the spelling of bur oak is sometimes burr oak, according to Sibley* it is also called a mossy-cup oak or blue oak. The Lady Bird Johnson Wildlife Center adds more names to this list, including Savanna oak, overcup oak, prairie oak, mossy-overcup oak. To add to the confusion, in certain terrains it can be referred to as scrub oak. It would appear some of its names are related to the various habitats in which this species, Quercus macrocarpa, grows. Alternatively, it refers to the appearance of its acorns.

This white oak is native to much of the eastern and midwestern United States and Canada, although its characteristics vary depending on its location. According to Iowa State University, this tree has the most variable characteristics of any of the oaks. For example, its acorns are large in its southernmost growth area while they can be about a fifth the size in the northern regions.

The overall height of the tree also varies by its habitat. In northern climates it may only grow to half the size of the same species in southern latitudes. This year saw a new national champion bur oak be honored in West Virginia. This specimen is a bit over 107 feet tall and has a trunk circumference of more than 278 inches. Models of climate change have predicted bur oak may have an increase in its range, but the locations where it thrives may also shift. Due to its long taproot it may be able to withstand drought conditions. OLYMPUS DIGITAL CAMERA

Its acorns can be the largest of the native oak species and are well fringed, hence its mossy-cup moniker. Its Latin name is related to the acorns; marco means large in Greek and carpa refers to fruit. One author states burr oak acorns in Texas are golf-ball sized! Iowas State University allows the trees do not bear fruit until they are 35 years old. Most sources state the trees can live 300 to 400 years. The university site also states the lumber of the tree can be used like white oak, but isn’t as valuable due to its many branches. The USDA mentions the most valuable bur oak trees for lumber come from Iowa and Illinois where it is usually marketed generically as white oak.

The trees provide food to 96 or more species of wildlife, including black bears. According to this article, acorns are the primary high quality food source for black bears in northeastern Minnesota. Cattle and other livestock may ingest seedlings and acorns even though this material may prove poisonous in large quantities. This same source specifically mentions the Cheyenne of Montana as having eaten a mixture of acorns and buffalo fat.

Like other trees in general, and other oaks in particular, parts of the bur oak have been used medicinally. A unique mention is made of tree galls used to treat intestinal problems and as an antiseptic.

The tagged Quercus macrocarpa in Fort Collins City Park was planted in 1979. It is located between the reservable shelter and the road to the golf course. Look for the electrical box painted with a black cat. If you point to the east at a diagonal from the box, you should be in line with the tree. OLYMPUS DIGITAL CAMERA

Sibley, David Allen. The Sibley Guide to Trees, 2009.

Native Oaks of Colorado–the Ubiquitous and Dichotomous Gambel’s Oak

Quercus gambelii is a tree native to the Southwest, including Colorado.

On the Fort Collins City Park Self-guided tree tour two oaks are listed as native to Colorado, the bur and the Gambel. Jennifer Ackerfield, Flora of Colorado, 2015, lists the Gambel oak as well as two shrubby oaks with which it hybridizes as native to this state. The USDA map shows the Gambel oak being native to states of the west and southwest, including Colorado, Wyoming and South Dakota. The USDA map shows the Bur oak as native to most of the Canadian provinces and the eastern United States as well as states north, south, and east of Colorado, but not Colorado itself.

According to the passage in Western Explorers and other sources, Gambel oak may also be called scrub oak. Ackerman agrees Quercus gambelli Nutt. can be either shrubby or a small tree*, but other authors call different species of Quercus scrub oak. Some of these also may be native to the region, and all of them do appear to be mostly shrubs. To add to the confusion, other plant databases also call Gambel Oak Rocky Mountain White Oak or Utah White Oak. This short article says Gambel oaks are well-suited to Colorado by their smaller form as they require less water than many of their relatives. The smaller size also helps them withstand wind and snow. This species is common in Grand Canyon National Park.**

Nearly all sources agree the wood from Gambel oak is mostly only good for fuel, although it might also have been used for equipment handles and furniture such as cradle.

Many concoctions of oaks in general (Medicinal Plants of the Mountain West, Michael Moore, 2003) and Gambel Oak in particular, have been used for gum inflammation, diarrhea and other intestinal conditions. Another use mentioned in the book is a chewed bolus of the leaves applied to insect bites. Other uses include as an analgesic for postpartum pain. Acorns have been eaten to increase sexual potency.

The acorns of this oak have very short or nearly nonexistent stems. The hairy cap covers less than half of the actual nut.*** Properly prepared acorn meal can be added to breads or soups to increase protein content. Some use acorns as a coffee substitute that does not contain caffeine. You can make your own or even buy it!

Although the Gambel Oak provides food and cover for wildlife such as deer and squirrels, it is considered poisonous for many domestic species, such as cattle and sheep. Gambel oak holds a similar dichotomous place in fire management. Under moderate conditions it may act as a firebreak, but in severe conditions it can be explosive and deadly.

Thomas Nuttall, one of the most famous naturalist of his time, named this species after a young naturalist. William Gambel was only 15 when he began working under Nuttall. Soon he ventured out to the Southwest and discovered a new species of oak near Santa Fe. Also on his journeys he found numerous new bird species, some of which also bear his name. Gambel named one of these, a woodpecker, after Nuttall. Eventually he returned to Philadelphia where he earned his medical degree and married a childhood friend. Shortly after this, he packed his bags and headed back to California for the gold rush and to set up his medical practice. During his trip, he contacted typhoid and died at age twenty-six.

To find the Gambel Oak (Quercus gambelii) specimen in City Park look for E59 on the map.

This tree is near the intersection of City Park and Bryan Avenue’s NW corner in a small cluster of trees. You can locate this cluster with the Gambel in the middle on the west side of the stone wall located between the derelict miniature train station and the road.

*Ackerfield, Jennifer, Flora of Colorado, 2015 p. 486

**Little, Elbert National Audubon Society Field Guide to North American Trees, Western Region, 1994 p.398

***Preston and Braham, North American Trees, 5th edition, 2002 p. 303

Quirky Quercus and the Leaves of its Genus

Old Ironsides was built out of a species of white oak.

Legislation was passed in November, 2004 proclaiming the oak tree the national tree of the United States. I suspect most of us think of oaks as large trees with majestic canopies and easily distinguishable leaves. Probably we think the leaves look like this:

But the number of trees in the oak genus, all of which are members of the Beech family, are reported to be between 400* and 600 worldwide. Michael A. Dirr and Keith S. Warren in their The Tree Book (2019) list the number as 530, including both deciduous and evergreen species. The outdated The Plant List includes at least 605 species and Tree Names lists 605 plants under Quercus.

There seems to be some question as to the number of oak species in North America, too. Many sources suggest there are about 90 species in the US and Canada (Dirr and Warren) while Sibley includes only 69 native species. There are at least nineteen species of oak in California alone. Many sources list the number of varieties in the US at about 90, but state there are at least 160 species in Mexico. The USDA map for Quercus shows all states except Idaho and all Canadian providences have native or introduced oaks.

On top of the large number of species, the various species easily hybridize, often making classification difficult. Within the two broad classifications of red oak or white oak, though, the trees do not interbreed. Some recognize an intermediate form of Quercus called golden oak. This subgroup may consist of only five species, although other sources state that there are none in North America.

Both red and white oak trees are used for furniture, flooring, cabinets, veneers and paneling. Historically only three species of white oak have been used in cooperage and for aging whiskies and wines.White oak is more often considered for outdoor uses as it has greater rot resistance. Live oak, a type of white oak, was used to build what is currently the oldest commissioned warship in the world, the U.S.S. Constitution. “Old Ironsides” was launched in 1797! Some of the ways to tell the difference between red and white oak trees, as well as their respective lumber, are discussed here.

Acorns give a clue as to whether a tree belongs to the group of red or white oaks, as well as a way to identify the various species. Acorns are also much more variable than I believed as a kid. Some are hairy, others elongated, a few tiny and some huge.

Red Oak with acorn — Note the large size of the cap of the red oak’s acorn.

Unfortunately, we have a lot of squirrels in our park and it is difficult to come across an intact acorn, but if you have an area with an abundance of acorns, this article discusses the foraging and processing of them for use in recipes such as Acorn Mousse and Acorn shortbread cookies. Guidebooks such as Sibley and the National Audubon Society Field Guide to North American Trees will usually include a picture or description of the nut to help with identification. While many species forage for acorns, other animals apparently can be poisoned when ingesting acorns, oak leaves, and bark. Acorns contain tannins and may be bitter. This can be remedied by repeated rinsing of the mashed meal.

Another reason acorns may be hard to come by in our park is the trees may not produce until they are twenty years old and the crop might not be considered a full one until the tree reaches fifty. According to this same source and others, the more bitter the acorn, the longer it will store.

An easy way to tell if an oak is a red or a white is by the leaf. White oak leaves generally have rounded lobes while red oaks have pointy tips. In many cases you have to look very closely as the tip is as thin as a hair.

Red oak tips — Leaves from three species of red oak

With the large number of oak species, it might be of little surprise that not all oak leaves look like you might expect. Some do not resemble that typical sketch above in the least. To complicate matters, the same tree may have leaves of distinctly different shapes! (Sibley, P

There are twenty-six tagged oak trees in City Park, although a number of these are hybrids or varietals. For this first post in a series on Quercus, we look at variations in leaf form. I have ignored the leaves of the hybrids.

Burr, others — The Oregon mountain oak has a small leaf while the burr (or bur) oak has larger leaves with many lobes. The typical leaf might have a more indented mid-section.

English Oaks — All English oaks, which are native to England, are white oaks. This can be seen in these three varieties rounded leaf lobes.

Graves and MOngolian — Note the rounded ends of the Mongolian and Chinkapin Oak, indicating they belong to the white oak group.

Red and Swamp — The swamp oak is a white oak although it is difficult to tell its lobes are rounded. The tips of the northern red oak, though, are decidedly pointed!

The photo below shows the Oriental White oak leaves growing on the tree. I would never have picked out either of these two leaves to belong to the oak family!

Although I do not have a photograph, as this tree is not on tree tour, there is a species called the Maple-leaf Oak. This endangered tree currently numbers only about 600. According to Sibley this oak is related to the Shumard, although the pictures of the leaves look more similar to maple leaves than the skinny Shumard leaf pictured below.

Shumard and Gambel — Shumard Oak (Quercus shumardii) a red oak on the left with its acorn and a Gambel Oak (Quercus gambelii) on the right.

*The Sibley Guide to Trees, David Sibley, 2009

Swedish Whitebeam-Don’t Let the Tag Fool You!

What do I know about the Swedish Whitebeam tree? It belongs to the genus Sorbus which is in the rose family. This large family of over 3000 species includes apples, cherries, plums, pears, and mountain ashes, as well as the flowers known as roses. Mountain ash trees are members of the same genus (Sorbus) as white beams and therein may lie some of my confusion in finding this speciman. I kept returning to the area on the tree map where this species was said to be located, but the unmarked trees in the area seemed to be true ashes and elms. The one unusual tree had leaves that were completely wrong. I thought I knew the smaller deciduous tree was an Oakleaf mountain ash as I’d read the tag the year before.

P9280006_01 — The darker green Sorbus intermedia in forefront

As the name implies, the Swedish whitebeam is not native to North America. As it doesn’t appear on the USDA maps, it must not be considered significant in the United States, although Toronto mentions it on its parks pages. In Great Britain it is suggested as a street tree. One source suggests it can withstand harsh conditions, is hardy to zone 3, and grows on Shetland Island. It may also be a tree useful for birds and bees.

The wood of the whitebeam has been used for handles, wheels and cogs. According to a few sources, the berries have been used to make bread and jam or used similarly to raisins. They may also be distilled into spirits.

As mentioned above, some of the confusion in finding this tree may be related to some of its attributes. Whitebeam are related to mountain ash trees and rowans. Tree Names lists fifty species of whitebeam, but also mentions whitebeams and rowans naturally hybridize. Some authors hypothesize that Swedish whitebeam are a hybridization of mountain ash and two other species or are derived from the Finnish whitebeam. With all the mountain ash genes involved, it isn’t surprising the sign on the Swedish Whitebeam

P9280001_01 — Swedish whitebeam with correct latin name on label.

displays Oakleaf Mountain Ash as a common name along with the latin name of Sorbus intermedia, or that of the Swedish Whitebeam. Seems like it just continues the confounding nature of the Sorbus genus!

P9280003_01 — The leaves of the Swedish whitebeam looking very similar to that of the Oakleaf mountain ash.

And why the two trees are so easy to confuse:

The tree on the Fort Collins City Park Self-Guided Tree Tour was planted in 1994 with a 2″ diameter. Although they are supposed to have white flowers in Spring turning to red berries in fall, no berries were visible in late September. This tree may live to 134 years.

To locate tree D192 Swedish Whitebeam (Sorbus intermedia), go to the southwest corner of the intersection of Sheldon and City Park Drives. This section is lined on the north and east by elms and ash trees with conifers making up the other boundaries. In the center are two conifers, the Engelmann Spruce and a Baker’s Blue Spruce. Of the three deciduous trees, the Swedish whitebeam is the most southerly and smallest. It is also the only one with a visible tag.

The Shellbark Hickory; A Tough Nut to Crack

Hickory ice cream is delicious

The taxonomy for the hickory tree is a little nutty. Members of the walnut family, Carya (hickories) represent about 25 species worldwide. Eleven are native to North America. Also a member of the walnut family, and of the same species as hickories, are the the trees which produce pecans.

The SHELLBARK Hickory (Carya laciniosa) is native to most of the eastern United States and Ontario. Like many other species, it has many alternate names including; big shellbark, bottom shellbark, kingnut, and thick shellbark.

Another moniker, bigleaf shagbark, may cause some confusion between the two types of hickory tree. Even though some say the flavor of the shellbark’s nut, with its difficult shell to crack, isn’t as good as that of the shagbark, a few plantations of shellbark trees have been established. The shellbark hickory can hybridize with pecans to produce a larger nut. It may crossbreed with shagbarks as well.

The wood of the shellbark, as with most hickories, is considered one of the hardest of the American native trees and is difficult to work as it tends to blunt edges. Because of the strength of the wood, it may be used to make chairs and rockers. The lumber also has a high BTU output, making it desirable as firewood. It is also used for smoking meats, such as in this recipe for hickory smoked turkey.

When in Portland, ME, I had the pleasure of eating a blueberry crumble with hickory ice cream at the Portland Harbor Hotel. I must admit while I was enjoying the very woody flavor I had no idea there was more than one kind of hickory tree. I include this recipe for hickory ice cream, which does call for shagbark chips, as well as one for hickory nut shortbread cookies.

Native peoples had numerous uses for the parts of the shellback tree, including the

innerbark for snowshoe rims and baskets and the wood for arrow shafts and blow darts. The shellbark hickory had numerous uses in traditional medicine including as an abortifacient, cold remedy, analgesic, an emetic, and a digestive system aid. Other uses included gun stocks and tool handles. The species has also been used to produce dyes and make soap.

Due to the large and long taproot, the trees may be difficult to transplant. They are slow growing as well. The nuts are food for many small mammals as well as turkeys and deer. There are many husks on the ground near the specimen tree, but none are intact, verifying their use as squirrel food.

The champion tree, crowned in 2018, is 109′ tall and found in Virginia. Although the height of the tree may depend on environmental conditions, Carya laciniosa are said to usually be about 60′ to 80′ tall. The specimen in Fort Collin’s City Park was planted in 1991 and had a trunk diameter of 3.5″.

Find D198 Shellbark Hickory (Carya laciniosa) along Sheldon Drive. The best way to describe where to find it is south of the intersection with City Park Drive. The tree is east of the shelter near the lake and almost directly west of the exercise station on the east side of Sheldon Drive. The nut husks are the give away as I don’t think this tree is labeled.

Carya laciniosa was used extensively by the Cherokee, according to Moerman (1998)