The American hazelnut (scientific name Corylus Americana) is a deciduous shrub part of the genus Corylus and the Betulaceae family that also includes the birch. As the name suggests, it is native to North America. It is found in the eastern parts of the continent, both in the United States of America and Canada.
This rhizomatous American hazelnut plants native to America can reach a height between 1 and 3 meters, with a main trunk that grows straight up. The American hazelnut plants usually form thick colonies. From the main stem emerge many thin ascending branches, forming an irregular zigzag pattern. They have a light brown bark, covered by many red hairs, with a glandular and stiff structure.
The American hazelnut is a deciduous species, which means that the leaves fall off during the winter. They have a broad oval shape and grow in alternate fashion, while the base can be round or shaped like a heart. The petioles are covered in glandular hairs with a stiff durability, while the leaves are green during the summer but turn red or orange as winter approaches. They have a length of 8 to 12 cm and a width of 12 cm and they are double serrated, with a hairy underside.
American hazelnut fruits resemble acorns in shape and size; they are wide light brown nuts not longer than 1 or 2 cm. They are encased in leafy bracts with rough teeth, similar to husks.
Every American hazelnut shrub has a large number of male flowers, which are very visible because they are grouped on long stalks. Near the tip of every branch there are two or three such clusters. Catkins with flowers only open in the spring but they form in the previous autumn.
American hazelnuts have both male and female flowers on the same plant, even if they are separate. All flowers are located near the end of branches but female flowers are hard to notice due to their very small size and the fact that bracts cover them almost completely. They are found in scaly grey or brown buds that group several flowers each and only the bright red stigmas are usually visible.
The scientific name of the genus comes from the ancient Greek word korylos, because the husks that encase each nut resemble helmets. The nuts are a major source of food for wild animals and birds. Some of the species that consume them in large amounts are foxes, deer, squirrels, northern bobwhites, woodpeckers, pheasants, ruffed grouse and turkeys. Deer and rabbits also consume the green leaves and stems. During the cold season, turkeys and ruffed grouse eat the male catkins as well. Birds and animals often use the shrubs for nesting and cover, due to the dense network of branches. Many insects consume the pollen during the spring, not only bees but also moths.
The American hazelnut bark can be used to brew a tea with astringent properties that is effective against fever and hives. It can also be prepared as an astringent poultice, which can speed up the healing of wounds, cuts or old sores.
Like all of the tree nut varieties, American hazelnuts are known to reduce the risk of heart diseases. This is caused by an optimal combination of vitamins and minerals with a role in heart health that are found in the nuts. They provide a large amount of fibers, which reduce the level of cholesterol. In addition, they include monounsaturated fatty acids that have the same effect of increasing the amount of good cholesterol (HDL) while reducing the bad one (LDL).
Several of the vitamins and bioactive compounds found in American hazelnut have a strong antioxidant action. They can neutralize the free radicals that damage cells and lead to many serious and lethal diseases like cancer. Vitamin E, which is found in American hazelnut, is a powerful anti-inflammatory agent that can prevent a number of chronic diseases and reduce the effects of aging. American hazelnuts supply a large dose of manganese, a trace mineral that is part of the structure of antioxidant enzymes. A single serving provides almost the entire daily recommended amount for this mineral. The nuts are also one of the best natural sources of PACs (proanthocyanidins), which are very useful polyphenols. Foods that include PACs, such as chocolate or red wine, have a specific astringent taste once inside the mouth.
All types of hazelnuts are considered to be some of the best foods for brain health. They provide a great mix of nutrients and bioactive compounds that maintain brain health and the cognitive function, while reducing the risk of the degenerative diseases that come with aging. Hazelnuts can be used as a natural dietary supplement, like a powerful brain food. They supply large doses of thiamine, folate, vitamin E, fatty acids and manganese.
Vitamin E has been identified as an essential nutrient for mental health and is also known as the nerve vitamin. It is needed for the health of the cognitive function and a good supply can prevent dementia, Alzheimer's, Parkinson's and other diseases that come with aging. Hazelnuts also provide manganese, an essential mineral that influences cognitive function among other roles. Thiamine is equally important for nerve maintenance all around the body and a lack of it can cause damage to the brain, so it critical to have a good supply from food. Fatty acids and proteins can repair nerve damage and reduce depression as well.
The American hazelnuts can be consumed raw but also used as an ingredient in biscuits, sweets and bakery products or cooked in soups. While the shell is very durable, the sweet kernels are well suited as a dessert. The nuts have a similar taste as other nuts but tend to be smaller than cultivated varieties. If you want the nuts to be sweeter and have a softer texture, harvest them before they become completely ripe. They mature during the middle or end of autumn and squirrels eat them quickly if they are not protected. It is possible to store the whole nut, including its shell, for about one year in a cool location. Nuts are rich in edible oil that can be pressed from them.
The American hazelnut is a popular choice for native plant gardens as an ornamental species. American hazelnut is especially valuable because it attracts local wild animals, which continue to return to the area. In cultivation, a hybrid between Corylus americana and Corylus avellana is often used. It is resistant to Cryptosporella anomala, a fungus native to North America, while producing larger nuts. It usually grows fast and produces a number of suckers; its final appearance is a large shrub with multiple stems.
American hazelnut is very tolerant, which makes it easy to cultivate. At least a moderately fertile soil is needed for good productivity but the plant will grow on very poor ones as well, including chalk. American hazelnut can also survive strong winds. Several named cultivars have been developed in the USA, where the American hazelnut is commercially grown. Like all other species from the same genus, American hazelnut can be moved even at maturity and it is very easy to transplant.
Loamy soils with good drainage are the best choice but other types are suited as well, with various pH levels. It grows best and produces the highest yield in sunny locations. It also succeeds in partial shade but it will develop slowly and the amount of fruits is reduced.
Seed propagation is a good option, place them in a cold frame during the autumn, immediately after they mature. It will already germinate by the end of winter, or sometimes during the next spring. It is also possible to use a stored seed but some preparation is needed: initially 2 days of soaking in warm water, then keep it is a warm location for 2 weeks and finally 3 or 4 months of cold stratification. At the right temperature around 20°C, germination needs between one and six months. Prick the seedlings as soon as they are large enough and move them into separate pots. At the end of spring or start of summer, you can already move them to their permanent position. Layering is easy to do and takes around six months. It is also possible to use suckers taken in early spring for propagation, which can be relocated straight away.