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corylus avellana

Importance to Oregon

Oregon’s Willamette Valley offers an ideal climate for growing hazelnuts. In fact, over 99% of all the hazelnuts grown in the United States are grown in the Willamette Valley.

In 1989, the hazelnut became the official state nut of Oregon. Hazelnuts, also called filberts, are grown for their delicious flavor. They are extremely nutritious, being an excellent source of Vitamin E, protein, and antioxidants.

Hazelnut orchard


Hazelnuts have been important in the diets of humans since prehistoric times. Evidence of the nuts has been found in many Mesolithic and Neolithic sites in Sweden, Denmark and Germany. Archeologists have also found the remains of filberts 5,000+ years old in prehistoric excavations from China.

Throughout history, people have believed that hazelnuts have mystical powers. Their branches were used as divining rods to locate underground springs, buried treasure, and minerals.

Doctors and herbalists have used hazelnuts to treat the common cold, persistent coughs, and even baldness. In ancient Rome, hazel torches were burned during wedding nights as a token of fertility and to ensure a happy marriage.

A historic 1636 image of a hazelnut tree
Photo source: The Herball or Generall Historie of Plants, John Gerarde

Hazelnut Names

Hazelnuts are known by many names including: filbert, cob nut, and Pontic. Its many names are a result of the varieties of nut sizes, shapes, and husk lengths. The name “hazelnut” applies to the nuts of any of the species of the genus ‘Corylus’. The term “hazel” comes from an old Anglo-Saxon word meaning “hood or bonnet”. The word “fil bert” comes from “full beard” and refers to the fringed husks which cover the nuts.

For centuries, the short-husked types were called hazelnuts and the long-husked types were called filberts. Some historians also think the source of the name filbert comes from St. Philbert’s Day, which happens in late August around the time when hazelnuts ripen and are harvested. In Turkey, the world’s largest grower of hazelnuts, they are called Findik.

In the early years of Oregon’s hazelnut orchards, growers adopted the name “filbert” to distinguish their superior nuts from the native, wild hazelnuts. However, in order to improve marketing, growers are now using the name hazelnut, the most universally recognized name.

What They Look Like

In Oregon’s Willamette Valley, the commercial varieties of hazelnut trees grow to be 20 to 40 feet high. The trees, which are naturally multi-trunked, are pruned into a single trunk tree by removing the lower limbs or suckers. This shape makes it easier to manage the trees and harvest the nuts.

Leaves: Hazelnuts are deciduous. This means the leaves drop off in the fall and new leaves emerge in the spring. The leaves are rounded, about 6-12 cm long and across, with soft hairs on both sides, and they also have a doubly-serrate margin, meaning the leaves have forward pointing teeth (serrations), and each tooth has smaller serrations on it.

Flowers: Hazelnut trees are one of the few trees that bloom and pollinate in the late winter before the leaves emerge. The flowers on the hazelnut are called monoecious. Monoecious plants have both male and female flowers on the same plant. The male flowers on a hazelnut are long, yellow catkins. The female hazelnut flowers are tiny red, purple flowers that are nearly hidden by the buds. Wind carries the pollen from male catkins to a tiny red female flower, where it stays dormant until May when the nut begins to form.

Fruit/Nuts: The fruit of the hazelnut tree is actually the nut. Hazelnuts are cross pollinated. This means two different varieties of trees are needed for the tree to produce nuts. About 6-10% of the trees in an orchard are pollinizer trees.

The nuts grow in clusters and are about the size of acorns. Each nut has a protective husk that covers all or part of the nut, depending on the variety. The nuts mature around the end of August, early September. The developing nuts are green. When they mature, the nuts turn a chocolate brown or hazel color. The nut falls out of the husk when ripe, about 7–8 months after pollination.

Catkins, male flowers
Catkins, male flowers

Female flower
Female flower

Hazelnuts in fringed husks
Hazelnuts in fringed husks

Ripe nuts are a chocolate brown or hazelnut color
Ripe nuts are a chocolate brown or hazelnut color


In the US, trees are planted in rows 15 to 20 feet apart. They start to bear, or producenuts about five years after planting. A mature tree can produce 20-25 pounds of nuts per year. Hazelnut trees on average can produce nuts for more than 50 years. Many Oregon growers are third and fourth generation orchardists.

A mature orchard is heavily shaded and the floor of the orchard is flat with very little grass or vegetation. This makes it easier to gather the nuts during fall harvests.

Hazelnut orchard


Hazelnuts are harvested annually in late September and October after the nuts have fallen to the ground. Unlike orchards in Turkey and Europe where harvesting is done by hand, US hazelnut harvests are mechanized.

Using a machine called a harvester, farmers sweep the nuts into rows and then vacuum them up. The harvester separates the nuts from twigs and other debris it vacuums up. The nuts are dropped into wooden tote bins that are then shipped to nut processing plants where they are cleaned, dried and sorted by size. About 50-60% of the nuts are sold in the shell.

The remaining nuts are shelled and sold as natural or roasted kernels. They may also be further processed by slicing, dicing, or grinding into meal, paste, and butter.

A sweeper makes its first pass as it centralizes the materials on the orchard floor

History of Commercial Growers in the US

The first commercial hazelnut stock Barcelona came to a nurseryman in New York around 1737 from Spain.

Explorers Lewis and Clark recorded eating native hazelnuts on their journeys and collected specimens to be used as nursery stock for propagation, research and sale. However, no successful commercial orchards were able to be developed in the east, Midwest or southern United States because of unfavorable growing conditions.

In 1871 Felix Gillet, who had established a nursery in California, believed hazelnuts would prosper in the maritime coastal valleys of Oregon and Washington. The hazelnut stock he offered, Barcelona, was some of the first to be planted in the area. Today, Oregon’s Willamette Valley, with its moderate climate, produces nearly 100% of the U.S. hazelnut crop.

Local Hazelnut History

While Oregon hazelnut orchards were initially dominated by European commercial varieties like the Barcelona, growers in the US have developed new varieties of hazelnuts that are suited to local conditions and resistant to the Eastern Filbert Blight. Examples of blight resistant local varieties include Lewis, Clark, Jefferson, Yamhill, Santiam and Sacajawa.

Local Timeline

First cultured hazelnut tree planted in Oregon by retired Hudson’s Bay Company employee, Sam Strictland in Scottsburg.

First significant planting by David Gernot: 50 trees planted along a fence row in the Willamette Valley.

George Steel buys 165 second-generation seedlings from Gillet, and plants them in Portland.

George Dorris of Springfield begins the first commercial orchard with over 200 Barcelona trees. The Dorris Ranch Living History Filbert Farm is still operating and open to the public.

Homer Kruse of Wilsonville, Percy Giese of Gresham, NE Britt of Newberg, Thomas Prince of Dundee and John Forbis of Dilley, purchase nursery stock from Gillet, and are considered pioneers in hazelnut growing. By the end of WWI, planting begins in earnest.

Where Hazelnuts grow in the World

There are native species of hazelnuts throughout the North Temperate Zone including Europe, Asia and North America. However, the ideal conditions for commercial growers of hazelnuts are more limited. Commercial growers need climates with mild winters, cool summers, moist, well drained soils near large bodies of water.

The top countries for hazelnuts are Turkey (70% of world production), Italy (18% of world production), and Oregon (3-4% of world production).

Despite their limited commercial growing area, hazelnuts are the 4th largest tree nut crop in the world, behind cashews, almonds, and walnuts.

The areas in red are where commercial hazelnuts are grown


Hazelnuts can be used raw or roasted. They can also be ground into a paste or flour. Hazelnuts are added to a wide array of dishes from cereals and breads, to soups, salads, yogurts and main dishes. Plus, hazelnuts are often found in confections, ice creams and pastries.Hazelnuts are also main ingredients in popular foods like Nutella. Hazelnut oil, pressed from hazelnuts, is strongly flavored and used as cooking oil.Inferior nuts are made into industrial oil. Some hazelnuts are used for livestock feed. Even the shells are used for mulch and landscaping.
hazelnut oil
Hazelnut Oil

hazelnut meat
Hazelnuts out of shells

hazelnut flour
Hazelnut flour

hazelnut shells
Shells are used for animal feed


Hazelnuts are rich in protein and unsaturated fat. They contain a high amount of essential oils and supply a well-balanced mixture of vitamins and minerals.

Hazelnuts also have a high concentration of vitamin E and it is also one of the few nuts to contains vitamin A, which is a natural antioxidant and has cancer-preventing properties. About 80% of the fat in hazelnuts is mono-unsaturated and thus heart healthy. Hazelnuts are also a source of folic acid, which decreases the risk of birth defects and heart disease.


Homemade Nutella


2 cups raw hazelnuts
1/2 cup unsweetened cocoa powder
1 cup powdered sugar
1/2 tsp vanilla
1/8 tsp salt
3 Tbsp hazelnut oil


Heat the oven to 400 degrees. Spread the hazelnuts evenly over a cookie sheet and roast until they darken, about 10 minutes. Transfer the hazelnuts to a damp towel and rub them to remove the thin outter skins.

In a food processor, grind the hazelnuts until they are smooth and butterlike. Scrape the sides as needed so they blend evenly, about 5 minutes.

Add cocoa, sugar, vanilla, salt and oil to the food processor and continue to process until well blended, about 1 minute. The finished spread should have the consistency of creamy peanut butter. If it is too dry, add in a little extra hazelnut oil. Put in a container, cover and refrigerate until needed. It will keep for at least a week.

Because it thickens when refrigerated, let the spread to come to room temperature before using.


the first commericial hazelnut stock to come to the US in 1737 from Spain

to produce nuts or fruits

the male part of hazelnut flowers

when two different varieties of trees are needed for the tree to produce nuts

a type of tree that loses its leaves in the fall and grows new ones in the spring

a leaf that has forward pointing teeth (serrations) and each tooth has smaller serrations on it

when male and female flowers on the same plant

roughly 6-10% of the trees in the orchard for cross-pollination to occur

the lower limbs on a tree trunk

AITC Resources

Oregon Hazelnut Video
Oregon Hazelnut Video

Grandpa's Orchard, Based on a True Story of an Oregon Family Farm
Grandpa's Orchard

Oregon Commodity Granola
Oregon Commodity Granola

Hazelnut Chocolate Spread
Hazelnut Chocolate Spread