native North American trees – What Tree Where

The Iconic American Elm is Still Hanging Around

An elm which had survived 14 bouts of Dutch Elm Disease was cut down while the 101 year old warden who had cared for it looked on.

The American elm (Ulmus americana), native to about two-thirds of North America, is an iconic tree and was one of the nominees for the National Tree. Although the oak received this honor, both Massachusetts and North Dakota call American elms their state tree. In the past, elms lined the streets of midwestern cities, college campuses, and the National Mall. The Oval at Colorado State University is still lined with American elms, some of which were planted in the 1880s. Elms dotted the upstate New York campus where I attended undergraduate school. I remember Dr. William Huntley lamenting the death of elms around campus, which might have been brought about by a more deadly strain of Dutch elm disease in the 1960s.*

I’m lucky to have three large elms on my property as the one on the southside tends to keep the house cool in the summer. Once a friend mentioned she considered elms the scrounge of the earth. I was surprised but then remembered the multitudinous seeds, more properly referred to as samaras, covering our sidewalk and how many seedlings I routinely yank out of flowerbeds. Without a doubt they are tenacious trees with a number of deficits, including that surfeit of seed production.

Elms may also harbor aphids which produce “honeydew,” nearly painting my white house a sticky black. European elm scale also contributes to the annoying honeydew and can debilitate a tree. Another pest, which chews holes through elm leaves, giving them a lacy look, is the elm leaf beetle. My house is now 102 years old, so I assume the trees are about the same age. I would not consider cutting them down unless they were rotten or became infected with Dutch elm disease. According to numerous sources, elms can live up to 175-200 years with an outside age of 300 years. The current oldest tree in the US listed on Monumental Trees, though, is estimated to be no older than 151 years.

Dutch elm disease started devastating stands of elms in the 1930s after the disease was carried to North America by European furniture makers in the 1920s. Known as a vascular wilt disease it can be transferred in one of two ways. First, native elm bark beetles, as well as European bark beetles, carry the disease-causing fungus. Dutch Elm Disease (DED) can also spread from the roots of closely planted trees. World-wide there are up to forty members of the Ulmaceae family but only six species are native to North America. All are susceptible to Dutch Elm Disease, but American elms are affected in the greatest numbers. Estimates are that 77 million trees were lost to the disease between its introduction and 1970. Current estimates of loss are closer to 300 million.

American elms (Ulmus americana) do still exist. Plant geneticists have created both American elm clones more resistant to DED, as well as cultivars which may prove to be less susceptible. Possibly the most famous elm tree was one which survived 14 bouts with the disease, thanks to Frank Knight, the tree warden of Yarmouth, Maine. According to the Liberty Tree Society, this elm was planted in the 1770s. Mr. Knight spent fifty years tending to Herbie, which was cut down in 2010 while the 101-year-old tree warden watched. You are able to join the Liberty Tree Society and purchase clones of Herbie, as well as support their research into viable cultivars. This site also has a timeline of the fight to save the elms

The study of DED tolerant elms continues. A cultivar developed in 1927, the Augustine Ascending elm, was once thought to have some resistance to the disease, although this has proven untrue. Of the 550 elms on the National Mall, a few of them are the Augustine Ascending cultivar. This variety may be noticeable due to its more upright nature. A specimen of Ulmus americana Augustine Ascending(B99) can be seen across the street from the tennis courts in City Park.

Another cultivar with properties beneficial to fighting scale was discovered by Fort Collins’ own Tim Buchanan, then City Forester. Scale buster American Elm (Ulmus americana Scale Buster) is located near the trolley station.

Although there is NO American elm listed on the current version of the Self-Guided Tree Tour, I have a sneaking suspicion this tree with its wooden American Elm sign is the same as the scale buster elm as a photo in the talk referenced above looks nearly exactly like the tree. This specimen is located behind the trolley station on the west side of the street. Before the leaves have bloomed it is quite easy to see its wooden sign if you are looking northeast.

The old marker designating the American Elm

*Sibley, David Allen. the Sibley Guide to Trees. 2015, Alfred Knopf.

Piñon Pine: Tastiest tree in the Southwest

Euell Gibbons may have proclaimed the piñon nut “the most palatable wild food.”

As you approach Santa Fe, you may notice hillsides covered with shrubby piñon trees. Nothing quite says you are in the Southwest as the crisp air carrying the scent of piñon pine. The smell of it burning wafts across the plaza in downtown Santa Fe. Plenty of stores carry piñon pine specialties, like piñon brittle, candies, nuts roasted with chile, and piñon coffee.

This species features in the traditions, legends, and ceremonies of many Southwestern cultures as described in a 1930s pamphlet from the National Parks Service. It may have been a major source of protein for Native Americans, including the Utes. For a modern discussion of the significance of the piñon to the Apache, this short blog includes a video and mentions piñon branches as smudge sticks. According to the site Pinenut.com, the nuts have had an economic benefit to the Navajo and in the 1930’s provided “more than the combined value of both rugs and silver which they produced.”

Piñon pine, Pinus edulis, is also known as Colorado piñon, Pinyon, common pinyon, New Mexico pinyon, Colorado pinyon, mesa pinyon, two-leaf pinyon, two-needle pine, nut pine, Rocky Mountain pinon, and Pino dulce. The preferred spelling, piñon, is Spanish and is interchangeable with most of the variations above. Although the USDA shows the trees throughout the Southwest, other sources indicate they are found primarily in Colorado, Utah, Arizona, and New Mexico. This discrepancy could be related to the existence of related species such as the single-leaf piñon, Pinus monophylla. Sibley* and others note the various species hybridize, making identification difficult.

Pinus edulis, the state tree of New Mexico, are “bushy” trees. They are slow growing but long-lived, possibly living up to 1000 years. The oldest verified tree was dated at 973 years, while the largest is located near Santa Fe, NM. As an alternate name suggests, this pine has two leaves in a fascicle, with the needles usually between 0.6 and 2.0 inches in length. The cones of the piñon are small, about an inch in diameter, and very round.* This species may not produce any cones until the trees are a quarter century old, with good seed production not starting until the specimen is 75 to 100 years old. As the fertilized seeds are comparatively heavy and not disbursed far by the wind, the species is dependent on birds to sow the seeds. Four species are primarily involved in this task: Clark’s nutcracker, Steller’s jay, Mexican jay, and the pinyon jay.

Although the seeds are what this species is known for, it is hard to beat its wood for a fire. The aroma is distinctive and quite pleasant. According to many sources, it provides nearly as many BTUs as hardwoods and has been called the “hardwood of soft woods.” Unfortunately, most sources lump piñon in with other pines, which might make sense on the national level. The benefits of burning in areas where it is available should not be overlooked. It is often cited as the best wood for chimineas.

The sap, or pitch, of the piñon has been used by Native Americans in the Southwest for various tasks such as mending cracks in bowls, waterproofing baskets, and as an adhesive. The medical uses of piñon are, in general, lumped in with the properties of other pines. A tea of the needles is used to ward off scurvy** or for its expectorant effect***. The inner bark could be used to dress burns and other skin conditions. Piñon is said to have an antiseptic quality. These last two factors are why it is used to make natural salves today. Mother Earth News suggests the antiseptic qualities make it a good bathroom cleaner and air freshener.

Today the nuts themselves are the stars of the piñon tree. Multiple places proclaim their nutritional value, from saying they are as protein rich as beef, to suggesting they may be a good source of polyunsaturated and monosaturated oils.

My first encounter with piñon nuts involved the difficulty of shelling them. My friends who had gone to college in Santa Fe, insisted the best way to crack them was with your teeth. Although this method is okay if you are going to ingest them raw or roasted for yourself, the idea of cracking nuts with that method and cooking with them for others seemed objectionable to me!

According to an undated article in New Mexico Magazine, a secret shelling machine was invented by the founder of Buffett’s, an Albuquerque mainstay since 1956. The article also states you can purchase shelled piñon from them but I was not able to find any for sale on their site at this time, shelled or not. You ARE still able to buy piñon candy from them, including piñon brittle.

Numerous sites discuss the differences between “hard shell” nuts, those which are from Pinus edulis, and the soft shell nuts, Pinus monophylla, or Nevada nuts. The nuts of Pinus monophylla are larger, more resinous, and not considered as tasty. Euell Gibbons may have proclaimed the piñon nut “the most palatable wild food.” Many websites warn against buying Nevada nuts when you are after piñons. The New Mexico Piñon Nut Company ships nuts. Pinenut.com explained the 2021 supply is limited as the quarantine kept pickers out of the trees.

Not only the Native American population of the Southwest harvests piñon; many Hispanic families also gather the nuts in the fall. In many areas of New Mexico you see cars parked along the interstate and people scurrying amongst the trees. Harvesting your own nuts is the most economical. Although it is legal to gather nuts for your personal use in certain areas, it is best to know the laws. Some people shake the trees to remove the nuts or cones, but the traditional method is to pick off the ground as seen in this short video. Less traditional methods of picking and preparing nuts are discussed in this article where the author suggests breaking open the nuts with a rolling pin.

Although most articles mention eating the pine nuts raw or roasted, recipes for their use abound. Fancy recipes such as pine nut soup, pine-encrusted pork, and a chocolate tart are including in this article from New Mexico Magazine. A number of recipes including candy and cookies can be found here. Native American Feast Day cookies feature piñons.

The piñon pine has also been used as a Christmas tree, living or cut. As is true for other features of the piñon, most lists of best trees for Christmas neglect to mention the species. New Mexico State University recommends them as having a good shape and says they are easily available for residents to cut. Every once in a while another publication will mention this conifer as a holiday possibility such as this bulletin from Washington state, which seems a bit out of their natural range!

A recent article discusses threats against piñon nuts and the trees themselves: climate change and cheap imports from other countries. Recent droughts have weakened the trees, which then are attacked by the ips, or bark, beetle. A study from California found higher temperatures decreased the viability of piñon pollen., while other studies have implicated heat death as the cause of the loss of between 40 and 80 percent of the trees. Not only are the trees and nuts endangered, but up to three quarters of the bird population may have disappeared in a decade.

Although it does little to solve the larger problem of the demise of the trees, it is still possible to use the logs as firewood if measures are made to destroy remaining beetles. In another glimmer of hope, the study mentioned above about the effect of heat, mentions a fungus that often grows with piñons may confer some drought protection.

By some reports nut harvests have decreased in yield by nearly seventy-five percent in less than fifty years. Indeed not all of the decline in piñon economy can be assigned to the change in climate. More than one article mentions the penchant for bulldozing trees in favor of ranchland or mineral and oil development as another factor leading to the decrease in productive piñons. The lower cost of imports doesn’t help the case for gathering the increasingly scare native product, either. In 2020-21 the cost of the nuts soared due to Covid-19 keeping pickers away.

In a 2014 publication, Rocky Mountain Forests at Risk, the authors discuss the importance of iconic trees in the Rockies and show possible scenarios related to drought, heat, and wildfire. They state the piñon-juniper woodlands are the most extensive type of forest land in the United States. They also mention piñons cultural significance as well as its role in water quality.

The Colorado pinyon (or piñon) pine in Fort Collin’s City Park

The Colorado pinyon (Pinus Edulis) can be found in City Park just northwest of Club Tico and across the road, near a power box. There are only two conifers in that area, and both appear to be piñon pines.

* David Allen Sibley, The Sibley Guide to Trees (Alfred A. Knopf, 2009, p.12)

**Linda Kershaw, Edible & Medicinal Plants of the Rockies (Lone Pine Publishing, 2000, p.36)

*** Michael Moore, Medicinal Plants of the Mountain West (Museum of New Mexico Press, 2003, p. 196)

The Difficulty of Defining a Fruit Tree, featuring Plums.

A tomato is actually a fruit but legally it is a vegetable!

What exactly is a fruit? My unabridged Random House dictionary has five definitions including: the edible part of a plant developed from a flower; part of plant growth useful to humans or animals; the developed ovary of a seed plant. (Random House Dictionary of the English Language, Unabridged, 1987.) More than likely the average person would say something along the lines of “the part of a plant that we eat” or name a few examples, such as a banana, raspberries, or apples.

Saying a fruit is the part of plants that we eat does not distinguish a fruit from a vegetable, but then some botanists would say there is no such thing as a vegetable. Instead they might identify what we call vegetables as the specific non-fruit part of a plant which we eat, for example, the stem (rhubarb, celery) or leaf (kale, spinach) or root (beets, carrots). The botanical definition of a fruit is simply an organ which contains seeds, but complicating matters is the legal case defining a tomato as a vegetable. Nix vs Hedden was settled in 1893.Yes, a tomato is actually a fruit but legally it is a vegetable!

The purpleleaf plum leaves at their greenest later in the year

All flowering trees (angiosperms) produce fruit, not all of which we eat. According to Gollner, there are between 70,000 to 80,000 plant species which produce edible fruits. Of these, only about twenty species provide the majority of what we consume.* Other sources are even more pessimistic and say the human species relies mostly on TWELVE species of plant.

Excluding citrus trees, nearly all trees producing the common fruits we eat are members of Rosaceae, or the rose family. Genus Prunus includes plums, cherries, apricots, peaches, and almonds, all of which are drupes or stone fruits. Apples and crabapples fall into genus Malus. Their fruits are collectively known as pomes. Pears, in the genus Pyrus, are also pomes. Fruit cultivation probably began somewhere between 6000 to 3000 BCE, primarily in the Fertile Crescent and Eygpt. Some of the earliest domesticated fruits included figs, dates, and olives.

For eons, fruits eaten raw were suspect, with Pliny stating pears were not digestible and Galen suggesting fruits were “troublesome in everyway.”** Early crops looked little like what we now consume. This link provides a few pictures of early fruits.

Prunus is the largest genus in family Rosaceae with the cherries and plums representing the most species. We do have native plums in North America, but information on all the species, often merely labeled “wild plums,” is difficult to come by. Some internet sources allude to many species, but the only place I found multiple species, about 30, enumerated was on a comprehensive map of wild plums throughout the United States. The accompanying blog post explains wild plums are becoming endangered due to the loss of animals (bears) to disperse the seeds.

The list of trees in City Park includes one native American plum (Prunus americana) tree. For nearly a year I have passed by where this tree is said to be located but have not been able to find a tag or determine any definitive characteristics (like evidence of fruit). It either isn’t there or is hidden in plain sight. Most sources list this species as being either a small tree, usually no taller than 25′ or a shrub with prickly twigs. The leaves, like others in this genre are serrated. The bark becomes scaly with age. The white flowers bloom prior to the leaves as early as March. Fruit is 1″ and turns reddish.***

Purple leaf plum was introduced to this county from Asia, is found mostly on the east and west coasts, although older literature shows a swath of the middle of the US as suitable habitat.

There are three purpleleaf plum trees in City Park, Prunus cerasifera Atropurpurea, also known as cherry plum, myrobalan or Pissardii. According to Dirr and Warren, the Atropurpurea variety is from the 1880s and may be the forerunner of many more recent cultivars. Although I have been observing these dark-leafed trees for a number of years, I have not noticed any fruit on them. This could be because, like the American plum, the fruit is only about an inch long. They do have beautiful pinkish white blossoms early in the spring. The foliage changes over the summer from deep purple to a dark green.

The plum trees from their deep purple to later green

To find the purpleleaf plums (C123), walk along City Park Drive from the exit on Jackson Street until you find a cluster of trees in a space encircled with rocks. When they are in bloom, they are easily identifiable by the color of their leaves.

If you want to try and find the American plum, walk along the ditch between Oak Street and Mountain Avenue and see if anything looks similar to a plum.

Dirr, Michael and Warren, Keith. The Tree Book: Superior Selections for Landscapes, Streetscapes, and Gardens, Timber Press, 2019.

*Gollner, Adam Leith. The Fruit Hunters: A story of Nature, Adventure, Commerce and Obsession, Schriber, 2008. p 23

**Ibid. p. 48

***Sibley, David Allen. The Sibley Guide to Trees.Knopf. 2015

The Cyme and the Bract: Other Lindens on the Tree Tour

Bracts are found on many plants and come in many different forms.

During bloom time lindens are easy to distinguish by their aroma and the clusters of small yellow flowers which resemble open tulips. After the flowers bloom and the seed, or nutlet, forms the linden can still be identified by the remains of the cyme, or flower clusters, and the bracts hanging along the branches. While still on the tree, bracts and cymes look like an extra, lighter green frill hanging below the leaves.

The term bract was new to me, although on investigation, most of us are probably familiar with them in some form and think of them as “flower petals.” Instead they are specialized structures which protect the actual flowers of various species. Often, as in the case of poinsettias and dogwoods, we mistake the colored bracts for the flowers.

Most of my resources say little about the cymes and bracts of the lindens. One website did talk about the bracts on lime trees, the British name for lindens. An interesting tidbit is that along with the flowers, bracts are harvested to make linden tea, which is known to help digestive disorders. It is also used as a sleep aid. The bracts alone may be made into a “beauty lotion” for cleansing the skin

Later in the year you have a clue you are under a linden when you find thin yellow leaves, which are actually bracts, under a tree. This year at least, these seemed to fall and scatter sooner than the actual leaves, but even when they are mixed with other leaves, they are distinctive in their thin, oval shape, rather like a tongue.

There are a number of other linden trees on the City Park Arboretum tour. Most of them are either hybrids or cultivars. I can’t begin to tell a Greenspire Linden from a Redmond, although the first is a Tilia cordata and the latter is Tilia americana. According to Michael Dirr and Keith Warren in The Tree Book: Superior Selections for Landscapes, Streetscapes, and Gardens, each of these two trees, along with the many other cultivars, has its uses. The other cultivars found on the Arboretum tour are listed below with information from The Tree Book mentioned above. Numbers correspond to those on the Arboretum map.

C126 Tilia americana Sentry is narrower than most other versions and may have some resistance to Japanese beetles.

C171 Tilia americana Redmond (C171) is said to be more urban tolerant that other lindens.

C148 Tilia cordata Greenspire has the best pyramidal shape.

C177 Tilia cordata Norlin is both a fast grower and cold hardy.

A83 Tilia x flavescens Glenleven is a hybrid between the American linden and the littleleaf linden and is known at the fastest growing linden hybrid.

E22 Tilia cordata Prestige. It seems little is written about this variety but it may be pollution resistant.

C178 Tilia x flavescens Dropmore The Dropmore linden is another hybrid which is viable to zone 2.

C 149 Tilia cordata Fairview is said to have larger leaves.

Tea and Chocolate–Products of the Linden?

Honey from linden flowers is said to be some of the lightest and best available.

OLYMPUS DIGITAL CAMERA — Profusions of yellowish white linden flowers

By far the easiest way to find linden trees is during and immediately after they bloom as the clusters of flowers (cymes) give the whole tree a distinctive look, as if the undersides of the leaves have been painted a lighter color. The flowers also give off a fragrance that can be discerned from a distance. Most of the trees are quite tall and if they are tagged, it may be difficult to find the tag, but there is little mistaking a linden in bloom. Also helpful in identification when they aren’t blooming are the heart-shaped, but saw-tooth-edged leaves. The straight trunk and bark also help identify the genus.

Lindens bloom between May and July, although many sources mention June as the primary bloom time. The very fragrant blossoms come with a single bract and hang down like lacy umbrellas. Others have described them as “fireworks.”

In the US the American linden (Tilia americana) is also know as American basswood or just basswood. The range of this native tree in North America is the East and Midwest. In England, its European relative (Tilia cordata) is known as a Lime tree or little leaf linden.

Most sources state our native tree grows to a height of around 70′. The National Champion tree in a Kentucky cemetery, crowned in 2017, has a height of 102′. There is a tie for the largest American Linden in Colorado, with one tree in Fort Collins and the other in Denver. Both are listed at a height of 92′. Monumental Trees lists the tallest American Linden in Europe at 101 feet and the oldest specimen in the Netherlands as about 138 years old. Other sources have suggested the species can live for a thousand years!

Monumental Trees lists the tallest Tilia Cordata at 132.87 feet. This tree resides in the United Kingdom. One source states a tree in Britain is over 2000 years old, but Monumental Trees lists the oldest as a mere 820 years. In North America, the little leaf has been introduced in the most northeastern parts of the continent, where the normal height is said to be 50 to 60 feet. The US champion (height plus girth plus branch spread) is in the state of Maryland and only towers 83 feet. Colorado’s champion can be found in Denver at 89 feet, with the second place tree, 72′, found in Fort Collins.

Native Americans made rope, netting, and baskets out of the inner bark, or bast, of the basswood tree. The wood is used for lightweight projects such as guitars and other instruments, carvings, yardsticks, and veneer. At one time basswood was the prime material for prosthetic limbs. The Iroquois carved the bark for ceremonial masks. The wood of the tree, being lightweight and fast-burning, may not be the best choice for heating.

According to the Kentucky Department of Horticulture, the American Linden was first cultivated in 1752. An oil derived from its seed pods was used as a replacement for olive oil, while the sap can be made into a drink or boiled into a syrup. Honey from linden flowers is said to be some of the lightest and best available. The preponderance of bees around the trees give rise to another of its nicknames, the bee tree, not to be confused with the Korean bee tree.

An usual product first made in the 19th century from the dried flowers and nutlets

was a chocolate-like substance. Unfortunately this concoction did not keep well and production ceased. In a short article discussing this “chocolate” the author says it is still possible to make some for immediate consumption or to freeze and includes a recipe.

The flowers of the tree especially have many uses. In France the leaves were made into a tea (tilleul) and used as a mild sedative.

Cup of Linden tea. The tea bags are slimy but the taste is pleasant.

Since the middle ages, the tea has been used to cure headaches. Alternatively the flowers could be added to a hot bath to help insomnia. Even today the flowers may be used in the making of perfume, As an early variation of “forest bathing,” sitting under the trees was thought to be helpful to epileptics.

Usually made from the European species, Tilia Cordata, linden tea is a well known use of the trees’ flowers, leaves, and bark. Unlike many medicinal uses of plants, linden tea has had a number of scientific studies conducted and papers written. Many benefits, such as relieving hypertension, stomach issues, and pain, helping you sleep, and a reduction of inflammation are reported in alternative medicine articles. Along with benefits, most of these articles mention a few drawbacks, such as possible heart problems and drowsiness.

To find the trees in City Park, follow your nose! The American Linden (Tilia americana) pictured in this blog is B98, which is across from the trolley station on S. Roosevelt Ave. There is another American Linden on the tree map at B101, which is located on north side of City Park Drive between fields 1 and 2. Tilia cordata, or the Little Leaf Linden (A 88), is also on the north side City Park Drive. It is the fourth stem in from the northwest corner of Roosevelt and City Park Drive, two down from the light post and near the little kids’ playground. These three trees almost form the points of an equilateral triangle.

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)

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.