National Audubon Society Field Guild to North American Trees

The Tree the British Play With: Horsechestnut

The World Conker Championships have been held since 1965.

Horsechestnuts (Aesculus hippocastanum), also known as Conker Tree in England, are in the same genus as Buckeyes. Both are part of the same order as the Soapberry tree.

These trees are planted as street trees for ornamentation as well as shade. Both the National Audubon Society Field Guide to North American Trees and North American Trees (Preston and Braham, 2002) report them as “escaped.” The USDA maps show them as introduced in both the East and the Northwest. The tree originated in the Balkans but has been planted widely throughout Europe and other parts of the world. They may have been introduced in the United States as early as 1576.

Monumental trees lists the widest trunked tree in England, the tallest at over 120 feet in the Netherlands, and the oldest as a specimen in France, which might be as old as 500 years. The leaves are palmate, radiating out from a central point. This species isn’t listed in the National Forest Registry, but the Colorado Tree Coalition lists the largest and tallest tree in the state as one in Cedaredge. The largest Red Horsechestnut can be found in Denver.

P5180055 — The leaflets radiate from a central post

The trees flower in May in what look like cones of white flowers. Sibley reports the interior yellow spots turn red when fertilized. The fertilized flowers produce what are known as conkers, or the “nut.” This is NOT the same as a sweet chestnut, and the outer casings look quite different. The two should not be confused as conkers are considered poisonous to humans, although they may be edible once boiled. Sweet chestnuts are encased in a spiny looking ball while the outer coating of a horse chestnut looks like bumpy leather. The interior “nuts” look similar but the edible version has a discernible and palpable point while the poisonous conkers are flat. Horsechestnuts are edible for many animals and are fed to horses and other livestock.

Apparently horsechestnuts are used in homeopathy. They are touted as useful for various circulatory problems such as venous insufficiency, phlebitis, and varicose veins when properly prepared. The leaves and bark may also be useful in a number of other conditions. Lupus is mentioned.

As they are not native to North America or The British Isles, there aren’t many myths associated with them. There is a game played in England called Conkers. This game is reported to have been a favorite of Roald Dahl. Currently, Britain’s trees are threatened by a combination of moths and disease. The loss of the trees may impact the World Conker Championship, which has been held in Northampton since 1965.

A notable characteristic of the Horsechestnut are the distinctive winter buds, which are large and sticky.

Below is a short video about the Horse Chestnut in the United States.

The Red Horse Chestnut (Aesculus x carnea Briottii) is a cross between a Red Buckeye and the common Horsechestnut.

The flowers are red or pink and it is the most common large red-flowering tree in temperate zones (The Sibley Guide to Trees). The flowers are quite stunning.

City Park’s Horsechestnut (Aesculus hippocastanum) (B115) can be found just west of the intersection of Jackson and Oak streets, across from 1312 W. Oak. This tree was planted in 1997 and had a diameter of about 3.5″

To locate the Red Horse Chestnut (Aesculus x crane Briotii) (A93), continue west on Oak Street to the first turn into the park. This street is a continuation of Roosevelt Avenue. The tree is one of the few deciduous trees in the NE triangle formed by Roosevelt and Sheldon Drive.

P5180008 — Close up of the Red Horse Chestnut blossoms.

How Many Names Can a Tree Have? The Alaska Cedar

There may be 36 or more common names for this tree!

The Alaska Cedar is native to the North American continent. This tree exemplifies the classification confusion that strikes amateur tree lovers. On the City Park tour guide (revised 2015) the Alaska Cedar, also called the yellow cedar, nootka Cypress, Stinking Cypress, and Yellow-cypress, the nomenclature is given as Chamaecyparis nootkatensis. National Audubon Society Field Guide to North American Trees, Western Region (1994), and the 2002 edition of North American Trees (Preston and Graham) agree with this designation, but the Gymnosperm Database lists the same tree as Cupressus nootkatensis while The Sibley Guide to Trees (Sibley, 2009) calls it Callitropsis nootkatensis. The USDA site classifies it as Family Cupressaceae (Cypress Family), genus Callitropsis (Nootka Cypress), species Callitropsis nootkatensis. The U.S. Forest Service lists THIRTY-SIX different names for this same tree! For the moment, I will just call it the Alaska Cedar and let the botanists argue. The University of British Columbia discusses this same dilemma and solves the problem by using the nomenclature C. nootkatensis.

Although some sites list this tree as growing for 300 years, conifers.org states the oldest tree has a ring count of 1834 and lists the tallest as a specimen in British Columbia of over 200 feet. The lumber of the tree has been used for exterior purposes such as shingles, decking, and posts. A few sources mention the crushed leaves of this tree do not smell good. When used as firewood, the wood has a high BTU output. Wikipedia mentions that a tree may last 100 years as firewood! Seems like it would have to be a very large specimen, though. Some of the unusual uses it has been put to is as stadium seating and toys.

OLYMPUS DIGITAL CAMERA — Alaska Cedar leaves

The Alaska Cedar may be another victim of climate change as a large number of these trees in Canada have died off in the last 100 years. This blog explains that the suspected cause of the die off is that these cedars have shallow roots that are susceptible to freezing, which can kill the tree. As the climate warms, the snowpack is not as deep or melts off early, leaving the roots exposed to cold night time temperatures.

The Weeping Alaska Cedar is a cultivar usually used for landscaping purposes. For its scientific name, add Pendula to your preferred name for the Alaska Cedar. It is thought that it can be grown in most of the United States.

The Alaska Cedar on the current Self-Guided Tour in City Park, Fort Collins, is E63. To find Chamaecyparis nootkatensis, head to Club Taco near the pool at the intersection of City Park and S. Bryan drive. This tree can be found across the street where the ditch and the fence around the miniature railroad tracks nearly form an angle. It is not known when this tree was planted.

The Weeping Alaska Cedar (Chamaecyparis nootkatensis Pendula) is located along Jackson Ave, across from 222 Jackson, near one of the exercise stations. This cultivar was planted in 1997.

Douglas Fir–an Imposter?

Did Hawaiians use Douglas Fir for their war canoes?

The Douglas Fir is possibly the most majestic of the trees native to Colorado and Larimer County.

P1010479 — The tagged Douglas Fir in City Park

Considering only conifers, in height in North America this species is second only to the Coastal Redwood. The tallest tree is listed at over 326 feet. Doug Firs are also listed as some of the oldest trees on the continent, with one recorded to be over 1300 years. Of course both the largest, tallest, and oldest of the trees are members of the West Coast Douglas Firs, which some consider a separate species than the Rocky Mountain Douglas Fir. Others list them as geographic varieties. (National Audubon Society Field Guide to North American Trees, Western Region, 1994; North American Trees, 5th Edition 2002.) Apparently the USDA does not distinguish between the two as the range map includes both the west coast and the Rocky Mountains.

In Colorado, the champion Douglas Fir, (Pseudotsuga menziesii) is in the San Juan National Forest. The tallest in the state was measured in 2014 at a height of 169″.

To add to the confusion surrounding this tree, it really isn’t a fir at all and has its own genus, Pseudotsuga. Some authors explain this is because it more closely resembles a hemlock while having traits of both spruces and firs. Most notably, the cones of the tree grow downward and not upward as do those of true firs.

The cones are distinctive with their fringy ends and have their own legend on how they got to look that way! P1030518

Like the true firs (Abies), needles are flat.

P1030528 — Flat needles with white stripes

This species is one of the most important trees in the western forest. Many animals use parts for food. Along with the usual medicinal uses of the leaves, bark, etc to treat various aliments, including coughs and colds, spring buds were used by at least one tribe to cure venereal disease. Parts of the tree were also ground to be used as a fertilizer. Like many other members of Pinaceae, smaller Douglas fir may make excellent and popular Christmas trees. Although the parts of the fir might not be a routine ingredient of the current American diet, the leaves can be used as a flavoring agent. A number of recipes can be found here and here. There is even a recipe for Gummy Treats.

Not only is the Douglas Fir important commercially in North America, but according to an article in WOOD magazine.com it has “migrated” to Europe, Australian, and even South Africa! Some of its commercial uses have included telephone poles, railroad ties, flooring, and paneling. The doors and most of the molding in my 1919 home are made of Douglas fir, and likely this same wood is seen in many west coast Craftsman homes. You could say this is continuing a tradition from ancient Puebloans, as they used the trees to construct their dwellings. Other uses included prayer sticks and a resin to coat buckets. The lumber is also used in boats, with the masts of the USS Constitution currently being constructed of it. The bark has been used to make a dye.

Probably one of the most surprising uses of the wood is that, even though these trees are not native to Hawaii, this was a preferred wood for Hawaiians to construct their canoes! Probably from logs that drifted ashore.

The tagged Douglas Fir (Pseudotsuga menziesii) in City Park is D196. To find this tree, head to the Northeast end of Sheldon Lake. You can park along Sheldon Drive or along the section of City Park Drive that is near the pool entrance. If you have been studying the Engelmann Spruce (D193) or Baker Blue Spruce (D194), you need only to climb up the short embankment through the tall conifers. No matter from which direction you approach this tree, if you see the huge green frogs (more Art in Public Places?) you are getting close. The Douglas Fir is south and east of the monstrosities. Depending if you are walking on the sidewalk that encircles the lake, or approaching from the street, the tree is either behind the swinging bench or in front of it.