CORK OAK INFORMATION ABOUT THE LANDSCAPE
The cork oak tree is native to North America. They are found in the southern United States from Texas southward through Florida and Georgia. They are often called the “Southern Pine” because they have similar characteristics with their thick trunk and branches reaching up into the sky.
CORK OAK TREES IN THE US: Where Do Cork Oaks Grow?
In the United States, cork oaks are not common. There are only about 1 million acres planted with them. However, there are several areas in which they occur in significant numbers. These include New England (Massachusetts), the Carolinas and Virginia, Maryland and Delaware counties along the Atlantic coast, southern Ohio and northern Kentucky. Other areas where they may be found include California’s Central Valley and mountain ranges east of San Francisco Bay.
Cork oaks are very drought tolerant. They thrive in dry areas such as deserts, mountainsides and rocky hillsides. Their bark is resistant to insect attack. In fact, it is one of the most durable hardwoods used for building materials.
They require little water or fertilizer and provide shade when grown in shady locations. In some areas they are used as windbreaks. The bark is harvested every nine to twelve years. It is an important source of cork for wine bottle closures and other products that require a natural barrier against liquids.
CORK OAK TREE FOR SALE: Can You Buy A Cork Oak Tree?
Yes, the cork oak tree for sale is available from specialty nurseries in the United States. Large commercial growers may also offer this tree for sale. However, availability in plants is limited. They may not all be of high quality and their size may be smaller than desired. If you are looking for a large specimen, it is best to find a grower in your area that can ship you one which has been harvested recently. Check with your local nursery or landscape company to see if they have trees available or know of a reliable grower in your area.
WHERE DO QUEERCUS OAK TREES GROW?
Cork oaks grow best in a Mediterranean like climate. This means they do best in hot, dry areas. The trees can also tolerate cooler and wetter conditions. They can survive in an arid desert or a humid rainforest. They grow naturally in the southwestern United States and as far north as New York. They can also be found in South America, Asia, North Africa and Oceania.
CORK OAK TREES IN THE LANDSCAPE
The cork oak tree is different from other trees due to its thick, rugged bark and unique, deeply furrowed wrinkles. It grows to be between 70 and 90 feet tall. It has a straight trunk that branches out near the top of the tree. The bark is dark gray or black and has a leathery texture.
The leaves are alternately arranged along the branches. They are dark green and oval shaped with 3 to 5 shallow lobes on the edges. They are between 2 and 4 inches long and have a bristly texture. The trees produce flowers in the spring. They are small, non-showy and grow in clusters at the branch junctions. They give way to acorns that ripen in the fall.
Cork oak trees are very easy to grow and maintain. They prefer dry, infertile and well-drained soils but will tolerate wet soils and poor soils that other trees won’t. They also do well in full sun or light shade. They have very few insect or disease problems and are not considered to be invasive.
HOW TO HARVEST CORK OAK TREES: How Is Cork Obtained?
Cork is a thick protective material that grows on the trunks of some types of oak trees. It can be harvested every 9 to 12 years without harm to the tree. The cork is stripped off and the tree continues to live. There are almost 1 million acres of cork oak forests in Europe, North Africa and Mexico. Most of these forests are not old-growth forests but plantations.
In Spain and Portugal, the cork is harvested from living trees. They are not cut down or damaged. They continue to live and grow. In Morocco and other areas the cork is harvested from dead trees.
The trunks are cut down and the cork is stripped off for processing.
The cork is made up of tiny filaments that grow between layers of wood. As the tree grows, the cork grows with it. They are very tightly compressed together so they can be very difficult to remove without damaging them. The cork must be stripped or cut off of the tree in large pieces.
They are trimmed and processed to make the finished product.
HOW IS THE CORK OAK TREE HARVESTED?
The cork is stripped from the trunks every 9 to 12 years when it has grown to approximately 8 inches in thickness. It takes about 9 years for the cork to grow to this size. The tree is then stripped of its cork and it continues to live.
In the 19th century, men called cork pullers would scale the trees with large knives. They would sit in a wet blanket tied around their waist to protect them from the thick coating of sap that would flow freely from the trees. The men would slowly work their way up the tree carefully stripping off long sheets of cork.
Once the cork pullers reached the top of the tree, they secured a thick rope around the trunk. Other men on the ground would then haul them and the cork off of the tree. The sheets were then tied together and placed on the ground to be processed into the finished product.
In modern times, a tractor is used to lift a worker up in a basket. The worker carefully cuts the sheets of cork free from the tree. The cork is then tied down to the basket and brought to the ground for processing. Large machines may be used but they are not necessary and they do not harm the trees.
The cork is then cut into pieces and sanded to make it smooth and easier to work with. To make flooring, tiles or bulletin boards, the cork is cut into different sizes so that it fits together nicely.
The cork is shaved very thin and glued onto a board. The outside slices of the cork are glued so that they overlap the next layer. This makes the board stronger and more water resistant. The boards are then cut to fit the intended flooring, glued together and sanded smooth.
Cork tiles are made from larger pieces of cork that have been glued together in different patterns to form a mat. They are then trimmed and sanded smooth.
Bulletin boards or blackboards are made from thin cork that has been glued to a framed piece of wood. The wood is shaped into the desired dimensions and the cork is glued on in the pattern desired. The back of the board may be painted or left unfinished.
CORK OAK TREE PRODUCTS
There are many different uses for cork. It can be used for flooring, tiles, bulletin boards and other speciality items. It is also used in a great many other applications.
Cork is used to make floats for fishing nets. The elastic cork is molded over a thin piece of wood and cut into various shapes. The floats help the nets stay on the surface of the water. They also keep them from sinking too deep and becoming inaccessible to the fish.
Cork is used to make shoe heels, buttons, card decks, bulletin boards, neckties and many other products. It can even be sawed into thin slices to be used as filters in water bottles and other containers.
If you are looking for a green and natural flooring material, cork is a great choice. Not only is it naturally occurring and renewable but it is also comfortable, quiet under foot and easy to maintain.
CORK TREE HISTORY
The cork oak tree is not a true oak tree.
Sources & references used in this article:
Landscape preferences in the cork oak Montado region of Alentejo, southern Portugal: Searching for valuable landscape characteristics for different user groups by D Surová, T Pinto-Correia – Landscape Research, 2008 – Taylor & Francis
Cork oak woodlands on the edge: ecology, adaptive management, and restoration by J Aronson, JS Pereira, JG Pausas – 2012 – books.google.com
Mediterranean cork oak savannas require human use to sustain biodiversity and ecosystem services by MN Bugalho, MC Caldeira, JS Pereira… – Frontiers in Ecology …, 2011 – Wiley Online Library
Drinking and protecting: a market approach to the preservation of cork oak landscapes by M Ahlheim, O Frör – Journal of Environmental Policy & Planning, 2011 – Taylor & Francis
Forest fires in cork oak (Quercus suber L.) stands in Portugal by JS Silva, F Catry – International Journal of Environmental Studies, 2006 – Taylor & Francis