Shagbark Hickory

Carya ovata

by John Brouwer

Shagbark hickory is characterized by its dark bark which forms long narrow plates curving outward giving the trunk a shaggy appearance. It produces large sweet nuts which are prized by people and squrrels. The squirrels usually win. Shagbark is also known as kingnut as it has the largest nut of all the hicorkies.

Hickory trees belong to the walnut family which also includes pecans and some other nut-bearing trees. Hickory grows to 80-100 feet and may live up to 500 years. Trunk diameter can be up to 3 feet. This is the northern limit of its Carolinian range. Although I have heard rumours of shagbark hickory in Waterloo woodlots, the only shagbark I found was in the Guelph arboretum.

Shagbark is likely scarce as it is very difficult to transplant. The germinating seedling forms a long taproot and in the initial years there is very little topgrowth as all the energy goes into the development of this taproot. In most cases the tree has to be started in place with seed or with carefully tended one year old seedlings. As a result shagbark is not found in nurseries although it does develop into a good landscape tree providing excellent shade with an attractive shape.

Native Americans ground up the nuts. After boiling the meal in water, the heat separated a cream-coloured pasty material which was used asa spread and ingredient in corn cakes and other dishes. Early settlers adopted the process, called it hickory milk which became valuable in trade – a quart of hickory milk was valued at 18 pounds of pork.

Hickory wood is very strong and flexible. It was used for bows, wheel spokes, textile looms, drum sticks, lacrosse sticks, It continues to be valued for tool handles and furniture. Hickory and ash were used for baseball bats. Formerly "reading and writing were taught to the tune of a hickory stick". Hickory wood is used in barbeques and smokers as it produces an aromatic flavouring smoke.

Hickory wood can not be used in veneers as the wood tends to split along its growth rings making it impossible to peel off thin veneers.

Because hichory has a very high heat value, a cord of hickory was equivalent to a ton of coal or 175 gallons of fuel oil, settlers prized hickory as fuel and used the wood smoke to cure ham and bacon. This led to the removal of hickory from woodlots and combined with the difficulty of reseeding and transplanting, is considered the major cause of hickory scarcity today.

A largely unknown but critical ecological role for shagbark hickory is its role as a roosting tree for bats. Bats require narrow chambers for roosting. As the bark is formed in plates which are only attached in their central sections, the tops and bottoms of plates provide numerous narrow cavities ideally suited for bat roosts. As bats control misquitos and other night-flying insects, quality roosts are essential for controlling insect populations. Trees have to be around 20 years old before their bark becomes suitable for roosts. But it becomes a longterm roost as the tree lives for several hundred years. In some areas, forestry departments have programs encouraging landowners to plant shagbark hickory in order to support bat populations.

The co-op presently has two shagbark hickory seedlings. One is in a cage behind the left visitor parking as you enter the co-op. The other is growing in the area behind the community center. As hickory seedlings focus their energy on growing a tap root during their first 3-4 years, it will be some years before these reach sapling stage and then another 15 years before they can become roost trees. Unless some enterprising beaver creekers start building bat houses, we can look forward to another 15 years during which mesquitos will have the upper hand.

July 2009