Hazelnuts are one of the most popular nuts in the world. They have been used since ancient times and they were even mentioned in the Bible! Today they are grown all over the world and sold at every grocery store. They are also cultivated for their delicious flavor. There are many varieties of hazels available, but there is only one type that produces edible nuts: Filberts or American Hazelnuts (Ficus religiosa). These nuts are named after the town in Virginia where they were first discovered.
The name “American” refers to the fact that these nuts originated from America. Some people believe that they came from North Carolina, however no evidence supports this theory. All of them originate from Ficus religiosa trees native to the eastern United States. The tree is found throughout much of Maryland, Delaware, New Jersey and Pennsylvania.
These trees produce nuts in two ways: by seeds and by fruits. Seeds are tiny, oval shaped and white. When the tree flowers, it releases thousands of small blackish-white seeds into the soil. These seeds germinate within a few weeks to a month depending on temperature conditions. If temperatures remain above 70 degrees Fahrenheit for several months, then the seedlings will develop into young trees with large leaves and fruit before reaching maturity.
Each seedling produces about 30 to 70 nuts. The trees flower between the months of May and July, and production of the fruit-type is highest in June and July.
The second way that American hazelnut trees produce nuts is by means of a fruit known as a “drupe.” These fruits are native to the eastern United States and are also found in Europe and other parts of Asia. They are small, oval-like fruits bearing a hard shell and a soft inside. Each fruit can contain one to three small, oval-shaped nuts.
A special process is used to grow these trees in a nursery, because they do not come from seeds. The trees are cut down when they are about 7 years old and the trunks are dried in the sun for about a year. Then, the bark and outside layer of the wood is stripped away. Next, the dried wood is sawed into flat pieces and dried again.
These flat pieces of wood are called “slabs.” They are stacked together into bundles and shipped to different parts of the world, especially to South America where they can be found growing wild. People cut down the trees and saw the logs into slabs just like they do in America. Then, gardeners plant the seeds or insert the slabs into holes in the soil.
In America, we usually insert one slab into the ground and just let it grow.
Sources & references used in this article:
Testing compatibility of hazelnut crosses using fluorescense microscopy by SA Mehlenbacher – IV International Symposium on Hazelnut 445, 1996 – actahort.org
Stigma Development and Receptivity in Almond (Prunus dulcis) by W Yi, SE Law, D Mccoy, HY Wetzstein – Annals of Botany, 2006 – academic.oup.com
Interspecific hybridization in hazelnut (Corylus) by V Erdogan, SA Mehlenbacher – Journal of the American Society …, 2000 – journals.ashs.org
Hazelnut pollination by JL Olsen, SA Mehlenbacher, AN Azarenko – HortTechnology, 2000 – journals.ashs.org
Pollination requirements of nuts in the Pacific Northwest by CE Schuster – 1941 – ir.library.oregonstate.edu
Hazelnuts (Corylus) by SA Mehlenbacher – Genetic Resources of Temperate Fruit and Nut …, 1991 – actahort.org
Pollen-stigma interactions following compatible and incompatible pollinations in hazelnut by CR Hampson, AN Azarenko… – Journal of the American …, 1993 – journals.ashs.org