About – What Tree Where

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

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?”

Ussurian Pear: the Most Cold Hardy of Pear Trees

This pear is hardy to USDA Zone 3!

Like all pears, cherries, apples, and hawthorns, the Ussurian Pear is a member of the Rosaceae or rose family.

OLYMPUS DIGITAL CAMERA — The flowers of the Ussurian pear tree. These were one of the first trees to bloom in the park

The tree, also known as the Harbin pear or Chinese pear, is native to China, Japan, Korea, and the Ussuri river area, which forms a border between Russia and Manchuria. It is the most cold-hardy of the thirty or so pear species and will grow in USDA zone 3.

The seeds for the tree were brought to the United States in 1926 by a professor from South Dakota who gathered them near Harbin China. This date is disputed by the Morton Arboretum, which states their tree was planted in 1922. The pome of this species is said to be small, hard and not particularly delicious although it might improve in flavor after a frost. The amount of sugar the fruit contains varies widely between varieties.

Some sources suggest it might be used for jellies. Although this website lumps the Harbin pear in with other Asian pears, it says the fruit may also have a tenderizing agent, making it good for marinades. In a chat group, another respondent suggested it might be worth trying to make a perry from the fruit.

In any case, the trees take up to eight years to produce fruit (pomes) and may live up to 300 years. The fruit is eaten by small mammals and birds. In the landscape the trees are used as a windbreak or as a specimen tree. Like most pears, Ussurian pears contain a compound that has antibacterial properties and may also serve as a flea and tick deterrent.

The Ussurian pear (Pyrus ussuriensis) in City park was planted in 1993 and had a trunk diameter of 3.5″. To find this tree: if you start at the intersection of Sheldon Drive and City Park and walk from the South East corner in a straight line south and east from the point of the intersection, you would find the tree between the the two playing fields.

Why a Blog about Tagged Trees?

It wasn’t until my twenties when I started wearing glasses on a regular basis that I realized trees weren’t green blurs, and most people could distinguish individual leaves. Soon after I noticed trunks in all their artistic contortions, various types of bark and burls. Later I tried my hand at marquetry and became enamored of the grains and patterns in wood.

2013-01-03 18.43.06 2 — Example of simple marquetry using four woods.

Earlier this month, I joined a short class, All About Trees, taught by local naturalist Kevin Cook. He handed out the list of trees in our city’s City Park. I live near this park. A few years ago, I noticed tags started appearing on various trees. Through reading the tags and utilizing the map the Forestry Department provides, I started to learn the species of trees, some with wonderful names. Currently I know where many of my favorites are located–the championship larch, some old redbuds, a Siberian Larch, crabapples, and weeping mulberries.

P4100045a — Blooming Redbud near a City Park exit

I liked the challenge of finding and learning more about each of the trees listed in the Self-Guided Tree Tour and thought my husband’s renewed interest in photography would make for an interesting project to tackle together. My plan is to highlight two or more trees per week until we’ve covered as many of the 220+ we are able to locate. Along with pictures of the trees during the season we’re doing the initial writeup, I hope to go back and add photos for the trees during other seasons.

My hope is this blog will be useful to others who are interested in trees in general and those in City Park in particular.