This is the post excerpt.
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.
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.
- Sibley, David Allen. The Sibley Guide to Trees, 2009.
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.**
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
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.
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.
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.
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.
*The Sibley Guide to Trees, David Sibley, 2009
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.
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
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!
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.
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)
None of the six tree books I consulted even mentioned this native tree
The possumhaw is in the genus Ilex, which consists of over 400 species of holly, some of which are evergreen and many of which are associated with Christmas. Alas, this neglected and oddly name shrub or small tree is not one of those with a legendary past. One source suggests its name comes from opossums feasting on its berries.
Most of the year, except for its shiny leaves, it is barely noticeable. It is, though, native to North America, growing mostly in southern states. The national champion tree is found in North Carolina and is but forty-two feet in height with a trunk of three feet in circumference.
One thing this humble plant does seem to have is a plethora of names and spellings—Possumhaw, Possum-haw, Possumhaw holly, swamp holly, meadow holly, prairie holly, winterberry, bearberry, welk holly, deciduous yaupon, deciduous holly—the last two names because, unlike the more famous hollies of holiday fame, this tree is not evergreen. No mention is made of uses for this shrub’s wood. Apparently it has no known medicinal value nor is it edible to humans.
Why then would you want to grow this? Birds and small mammals eat the berries in the winter. It may be a host to a species of butterfly as well as bees and other nectar insects. And the berries are delightful in winter, providing color to a bleak landscape.
If you are looking for E61 Possumhaw (Ilex decidua Grace) on the City Park Tree Tour in winter, it should be easy to spot in the enclosure across from the pool, near the miniature train station. Of course it is located in the same spot the rest of the year, but you may need to look more closely to find it!
Lumber from the tree was crafted into prosthetic limbs.
When you look at the Ohio Buckeye (Aesculus glabra), it isn’t surprising that it is in the same family as the horse chestnut tree. Along with the maples and soapberries, buckeyes are members of the order Sapindales. The genus of the tree, Aesculus, is derived from the name of the Greek god of medicine.
Not surprisingly, the Ohio Buckeye is the state tree of Ohio (designated in 1953) and the symbol of Ohio State University. Despite its name, it is also native to many of the eastern states and Texas. The current champion tree can be found in Kentucky. It may be one of the few trees associated with a political campaign, that of William Henry Harrison in 1840. Buckeyes were also one of twenty-one species under contention to be the National Tree but lost to the oaks.
The “nuts” of the buckeye are poisonous when eaten raw but are edible once the tannins are leeched out or the nuts are roasted. When boiling the nuts, the resultant tannins can be used to tan leather.
A powder made of the buckeyes was also used by Native Americans to stun fish in ponds. If the above makes the idea of eating the nuts sound less than pleasant, there are also medicinal uses, such as using the powder in a salve for rashes and sores. The buckeye may have also been used for cerebral spinal treatments. A tea made from the bark may also help varicose veins and hemorrhoids. Lumber from the tree was put to another unusual medical use as it was crafted into prosthetic limbs!
Even though the fruit of the tree may not be something you want to eat, there is a candy called buckeyes. Basically they are a peanut butter ball dipped in chocolate.
To locate A86 Ohio Buckeye (Aesculus glabra) on the City Park Tree Tour, park along City Park Drive near the pool The Buckeye is in a line of trees between the two playgrounds. It is the largest of the trees and two in from the street.