The Hazelnut Plant
The Hazelnut Plant: origin and cultivation
The botanical name of the hazel plant corylus avellana comes from the Greek word koris, meaning helmet, and Avella, theancient Roman town near the city of Avellino.
The hazelnuts are fruits of corylus avellana, a plant dating back to the end of the glacial era ( 10,000 years ago). Fossils offer evidence that the fruits of this plant were essential part of a primitive men’s daily diet which consisted primarily of berries and wild fruits. The hazel was one of the very first fruit plants cultivated by humans. It originated in the Mesopotamian region and quickly spread throughout Europe, especially the Mediterranean and Balcan areas.
Hazelnuts were much appreciated by both Greeks and Romans for their nutritional contents and even considered to have therapeutic as well as magical effects. In ancient Rome hazel wood was used to make magical wands and hazel branches were offered as symbols of happiness. Because of its association with fertility, in medieval France the plant was given as special gift at weddings. People in medieval Italy believed even that magicians could communicate with the dead using hazel branches.
During the first and second world wars, when Europe was suffering from major food shortage, many families began using hazelnut oil as an alternative to olive oil.
Today hazelnut cultivators are concentrated in Mediterranean countries like Turkey, Italy, Spain, Greece and France. Turkey is the world largest producer ( 70%), Italy is second ( 15%) with high quality production in the regions of Lazio, Campania and Piemonte.
Large scale production of hazelnut, called coryliculture, in the Piemonte region began at the end of 1800, when local vineyards were destroyed by the phylloxera bacteria and farmers had to look for alternative cultivations. Since then, hazel cultures have increased steadily year after year. Following world war II, the high quality of Piemonte hazelnuts began receiving worldwide recognition; their demand surged propelled by new confectionary industries like Ferrero, Novi and Nutkao.
The official denomination of hazelnuts produced in Piemonte is “ La tonda gentile trilobata del Piemonte” . The nuts produced here are the “mother” of Nutella, Gianduiotto, Torrone and Amaretto.
The largest consumer of hazelnuts are the Swiss ( 2 kg/person/year): they use the nuts as a major ingredient in their chocolates.
Flowering of the hazelnut plant
The hazel plant is actually a large bush about 5-6 meters high, with long thin branches and rounded, toothed leaves, It prefers rather mild temperatures ( late frost can damage it). It produces fruits 5 years after planting ( constant production after seven years)
Flowers appear very early and have a rather unique shape. They are wind pollinated because it is still too cold for insects to be around ( between December and March)
The plant is Monoecious, meaning both male and female flowers arepresent separately in the same plant.
The male flowers, the catkins, appear at the end of the Fall on the branches from the previous year; they are pale yellow, 5-12 centimeters long and grouped in elongated “ears”.
The female flowers appear in February at the tip of the male catkins; they are very small in size with a pale red color. They get pollinated between February and March.
These flowers are the very first food source for bees during early Spring.
The female flowers must be pollinated with pollen from a different variety since they are not compatible with the pollen of their own variety.
In most of Piemonte hazel farms, pollination is done with pollen originated from wild hazel varieties surrounding the cultivar. An optimal hazel cultivar should have 8-10% plants from different and well established varieties, in order to ensure maximum pollination and large productivity.
The ideal variety to pollinate the Tonda Gentile Trilobata del Piemonte is the Tonda Gentile Romana.
The period between pollination and fertilization ( the union of male pollen with female ovules) is long ( 3-4 Months) and delicate ( it does not like freezing temperatures) and culminates with the early stage of fruit formation.
Growth of the hazel plant
The hazel plant produces its fruit on the branches of the previous season. The fruit begins forming right after fertilization and matures completely first by thickening( the embryonic hazelnut changes from a spongy mass to a soft milky seed to a hard seed) and by veraison ( the fruit changes from a milky to an ivory color).
The fruit is a nut, produced in clusters of three or five, andheld in a leafy greenHuskoften blending with the leaves of the plant.When ripened, the nut is brown in color, roughly spherical, with a woody hard shell. The nut is fully ripened in August or early September.
Hazelnuts are harvested in mid-Autumn when the trees drop their nuts and leaves ( often times they are shaken from the tree). The harvesting of the Trilobata del Piemonte is done mostly by mechanical raking of fallen nuts using large sweepers and harvesters ( they look like giant vacuum cleaners).
Hazelnuts cannot be left on the ground for too long, otherwise they risk being damaged by humidity or wild animals. After harvesting, the hazelnuts should be dried for 2-3 days in open air ( some large growers utilize industrial hot air driers for this task.
In order to preserve the flavor of the hazelnuts they should be kept in dry places.
Because of the rapid expansion of hazelnut cultivars, there are now over 30 specialized nurseries and greenhouses in Piedmont providing high quality young hazel plants for both large and small growers.
The hazel is a beautiful plant all year round thanks to its unique flowers,fruits and leaves. The plant is very easy t propagate with most economical and simple method being from the root sprouts.
All hazel plants produce numerous root suckers around the collar of the plant (at the base of the branches). These need to removed and transplanted with their roots to a pot of loose soil. Most propagation should be done at the end of the summer or beginning of spring.
Nutritional value of Hazelnuts
Since ancient times, hazelnuts have been much appreciated for their rich energy content. One hundred grams of hazelnuts contain 600 calories, 60% fats, 15 % proteins and 5% sugars and 20% other compounds ( water, minerals). The fat components present in the oily hazelnuts are monounsaturated fats, which are rich in good cholesterol and fatty acids. They promote production of Omega3 and protect body tissues from aging and from cardiovascular pathologies like atherosclerosis. Hazelnuts are also rich in Vitamin E, potassium, phosphorous, magnesium, all elements that counter the symptoms of fatigue and promote faster metabolism.
Hazelnuts can therefore be a very important health ally. Eating some hazelnuts on a regular basis during the cold season helps to better withstand the cold and to conserve energy.
Hazelnuts are also used to make various types of oils: both for cosmetic and comestible use.
Hazelnut oil for cooking has a sweet and penetrating aroma, a yellow straw color, and high mineral content.
The cooperative for the protection of the Tonda Gentile Trilobata del Piemonte produces an IGT oil for domestic use: it is an ideal condiment for salads and many other dishes.