A Little Hazelnut History

Do hazelnuts grow in North Dakota? You may be surprised learn that hazelnuts are a native shrub that grows naturally in both North Dakota and Minnesota. They might even be growing near you.
I read that hazelnuts were some of the first plants to colonize this area after the glaciers melted about 10,000 years ago. I was a little skeptical at first, but after finding hazelnuts in so many places in North Dakota, and the fact that each plant had such different characteristics. Some were very short about 3 feet high while others were over 15 feet high and the husk which covers the nut on some are a smooth leaf like structure and others have a very fat, juicy husk with little hairs.  Some are growing in heavy high ph soils, some growing in sandy dry soil, and some growing in low ph bogs with blueberries. For the same plant to occupy so many different types of locations it must have taken many years to adapt to all these different types of ecosystems.
Officially there are two species of hazels native to this area, the American hazelnut (Corylus Americana) and beaked hazelnut (Corylus cornuta).

This is one type of American hazelnut that I've found in the northern part of our state.
It was about 4 feet high and had a leafy type of husk with 2 or 3 nuts in each cluster.
This plant is a multi-stem suckering shrub and the stems are usually less then 1/2 inch thick.
This one plant can take over quite a large area, and is probably something that you would not want in a small garden.

The small green cylindrical columns hanging from this American hazelnut branch are catkins (male flowers) that develops on the plant in the late summer and will open the next spring to release pollen for the female flowers on the neighboring plants. Hazelnuts are not self pollinating, so two or more plants are needed for a good nut crop.
On this plant a single catkins hangs underneath each leaf node. I've found most wild hazels in North Dakota have this characteristic of single catkins, which is unusual because most other hazelnut varieties have multiple catkins hanging from one leaf node.

This beaked hazelnut is usually found as a understory shrub located around some lakes in low ph sandy or loamy soils. The nuts have a long hairy beak like husk, which can irritate your hands when picked. They usually are in cluster of 2 but I've also seen them in clusters of 4. The nuts are small with a thin shell with a fair taste.

The leaves of both types of hazelnuts are very similar being alternate, simple, with double toothed margins. As you can see the best way to identify which type is by the husk or the catkins. 

I've tried growing these beaked hazels in heavy high ph soils in this area of the Sheyenne River and have only managed to grow just the one shown above. 

These are the dual catkins of the beaked hazel, and are always pointing in an upwards direction.

This makes identifying a beaked hazelnut during the late summer, fall, and winter very easy.

The female flowers of both hazels are really hard to tell apart, except for the fact that beaked hazelnut blooms a week later then the American hazelnut. 

The big differences of the American hazelnuts have really fascinated me. This plant was growing in an open area in the Sheyenne Grasslands south of Leonard ND and is over 15 feet tall and with stems that are over 2 inches thick.

The fruit of this hazel that grows in this open area has a fat and juicy husk around a thick shelled nut.

I found hazels growing south of Valley City in small state park with a creek. The trees in this area are mostly oak. Some of the under story shrubs are choke cherries and hazelnuts with buckthorn taking over parts of the under story. 

Here I'm investigating the hazelnuts on the edge of this wooded area in the park. Most of these plants were about 5 feet tall and produced large amount of nuts every year. I assume that the squirrels concentrated on the large amount of acorns that ripen earlier then the later thicker shelled hazelnuts.

These are the hazelnut from  Little Yellowstone Park.

The husk on these are almost perfectly round, and juicy.

It has a medium sized nut with a thicker shell then most American hazelnuts, and the taste isn't too bitter.

These hazelnuts growing in Oregon are European hazelnuts (Corylus avellana) and would be multi-stem shrubs but they remove the suckers and are trained to grow as small trees. 

There are also hazelnuts that grow as a large sized tree called a Turkish tree hazelnut(Corylus colurna). These 40 to 50 foot trees produces low numbers of small nuts and takes 7 to 10 years to produce nuts.

This European type of hazelnuts is one of the larger nuts that drops out of the open husk when ripe. They are then swept up off the ground, washed, and processed. 

These are the catkins from a European hazelnut. 

These type of hazelnuts always have multiple green catkins hanging from one leaf node.

Easter Filbert Blight (EFB) is a fungi that affects most European hazelnuts which have little or no resistance and usually succumb to this disease in 2 or 3 years.

Most American hazelnuts are resistant but will carry EFB.  There are now a few universities and other groups crossing hazelnuts from around the world to find a resistant verities of plants with these same large nuts.

Almost all of these European hazelnuts are not hardy enough to grow in North Dakota.

I started an orchard near Horace, ND in 1978 with some native American hazelnuts from Northern Minnesota and later added collections from elsewhere including the Sheyenne Grasslands. I then purchased some hazelnuts with the European back ground including some three way hybrids. Almost  all of these did not make it through our winters, but a few did and with that genetic diversity I began picking and growing out nuts with a larger size, thinner shell, and the better flavor like that of the European filberts, but with the cold hardiness of the American hazelnuts.

I also began picking other traits such a non-suckering, more of a tree like structure, and a plant in which the nuts could be easily removed from the husk.

I also found that some of these new varieties were not resistant to Easter Filbert Blight and I lost some of my best plants. Now EFB resistance has become another trait I'll have to consider.

The hazelnut in the picture above is one of my plants with more of a tree like structure, but does produce one or two suckers every year. Even more important is that it's resistant to EFB.

My latest projects are hand pollinating and cloning some of my best plants.

The hazels in this picture are all either hand pollinated or clones, and this spring almost all will produce nuts for the first time. 

This is not a hazelnut but the nut of a buckeye. 

I thought you might what to see something another then hazelnuts

Hazelnut Harvest 2019

Fall 2019 and just finished another harvest.

I'm often asked, "how do you know if they're ripe and ready to be picked?"

On some plants when the husk starts to change color to a darker tone it's a good indication that they are close to being ready.

Another indication is when the nut turns a dark brown as shown in this picture.

On this plant the juicy husk begins to dry up and change color.

This hazelnut husk has no color change, but it still might be ready.

On this picture I'm checking for a little darkening of the nut.

The next step is to try to roll out the nut with your thumb.

If the nut rolls out easily it is ready to be picked. 

I do this in 3 or 4 locations on the plant to make sure the whole plant can be picked.

This is that same plant after all the nut clusters have been removed.

Each of these mature hazelnut plants usually fill a bag like this one.

The next step is drying and removing the husk.

Every one of my plants is a little different, and on this plant the nuts drops out of the husk when ripe.  To pick this one I lay a tarp on the ground and just shake the stem letting the nuts fall on the tarp. The biggest problem is not all the nuts are ripe and ready to fall at the same time, so I have to shake the plant every day for a week until all the nuts are gone.

These are pictures of hazelnuts that may look like they are ready to

pick but they are not, because they failed the roll out test.
If they were picked at this time the husk will never release the nut even when dried down.

Another question I'm often asked is "How do you pick the nuts when they are on tall stems which might be over 15 feet?"

Hazelnuts have very flexible stems which can be easily bent down as show above.

I lay down a tarp then bend the stem and shake it. This will drop about half the nut clusters on the tarp and the rest will have to be picked by hand.

The next step is drying down the husk so the nut can be removed.
 I first place them on drying racks for a few days and then in mesh bags when the husk is completely dry.  After harvest I will run them through a separation and cleaning process.

In this picture you can see how drying down the hazelnuts took over my whole green house.

These are a few that have been cleaned, tagged, and bagged.

Next step evaluation.

Few interesting things this year 

I was surprised to see nuts growing on one of my layered clones that I just planted this spring.

While visiting the Aneta Community Orchard, I thought these where my hazelnuts but Bill Miller later informed me that they were from St. Lawrence Nursery and the ones Bill got from me were in a different part of the Orchard.

Bill Miller has done a great with the Community Orchard and if anyone is in the Aneta area they should stop and take a tour of the orchard.

I also visited Greg Krieger's home where he was showing me the nuts on this hazelnut plants that he had purchased from me. We also looked at his many other plants and fruit trees. We enjoyed sampling  the fruit from his apple and pear trees.

These are hazelnut clones from green cuttings that Jim Walla propagated.

This is something that I thought couldn't be done but Jim propagated these 15 from one of my superior plants. I'm just amazed at the things he does.

Now it's my job to harden them off and see if they make the winter.

This is my favorite T-shirt that I received on my birthday from my daughter Kelsey.

Thanks Kelsey😏👍

Well, it looks like fall when the wild hazelnut starts to change color.

This plant is my first hazelnut that I planted in 1979 from Albert Lee's farm in Northern Minnesota  near Roseau.  

Squirrel devastation

Squirrels have started removing the hazelnuts on 19th of July. This is the earliest that I've ever seen them go after immature hazelnuts.

I have 5 live traps and 4 rat traps and started using my pepper spray.  In less then a week I removed 11 squirrels.

I've even seen the smaller red squirrels hanging from the branches eating the unripe nuts.

The larger grey squirrels finish off the ones that fall on the ground.

This is what it looked like the first day that I noticed the problem.

The next day really took me by surprise and I thought this may be really serious, so I mixed up my pepper spray and bought some more traps.

This is the pepper spray recipe I use for my squirrel deterrent, but now I started adding 4 cloves of garlic with the peppers in the food processor.

Hot Pepper Spray for Squirrel Deterrent 

(WEAR GLOVES! Goggles aren't a bad idea either)

Red Cayenne, Jalapeno, or habanero fresh peppers (cayenne for stronger mix)

Put 3 Peppers in a food processor with enough water to make a liquid.
Strain through cheesecloth into a quart jar
Add 2 tablespoons Olive/Vegetable oil
Squirt of Elmer's glue
2 drops liquid dish-soap

Use 1 part of mixture to 10 parts water

Shake well
Spray on plant with spray bottle.

(Don't make it any strong then 30%)
Be careful not to get this in your eyes.

The new crop of hazelnuts 

This is some of the new crop protected by the pepper spray.

This is a large leafy hazelnut husk that usually matures the end of September.

I'll have to spray once a week to keep the squirrels off this plant.

This is another one of my better plants that ripens around August 18th.

On this plant the nut tends to drop out of the husk in the first week of September.

This is another one of the better plant that will have to spay to keep the squirrels away.

I just noticed a weevil hole on the husk which I've circled. Just one more pest to deal with.

This plant has a large juicy husk that squirrels do not like, but the nut is also hard to remove when ripe.

This is another one that squirrels tend to not like.

This is one that squirrels really tend to go for so I'll have to spray this one.

This is not one of my better plants, but I like the unusual look of the husk.

Field day at the Carrington REC

During the field day at Carrington REC, Kathy Wiederholt showed a row of my hazelnuts that they are testing in their  hardy fruit evaluation project.

This is a close up of some of the developing nuts at Carrington REC.

This hazelnut plant that Kathy showed here has very large clusters of nuts. 

It looked like there might be 8 or more nuts in each cluster, which some times makes it hard to remove the nuts from the husk. I prefer no more then 4 nuts in a cluster.

This is another type of hazelnut in the same row, which just has singles and no more then 2 in each cluster. This type of plant is usually easier to remove the nut from the husk.

I would like to thank Kathy Wiederholt, fruit project manager in Carrington, for doing such a great job evaluating all the different types of hardy fruits that will grow in this area.