Hazelnuts summer 2021

A new beetle attacking hybrid hazelnuts

Copyright © 2014 tom murray

This is one of the jewel beetles, Agrilus pseudocoryli, that can cause the dead and dying branches of wild and hybrid hazelnuts and may be causing damage in the Lino Lakes area.

While visiting my son in Lino Lakes, MN, I noticed some dead branches on his hazelnuts.

Below the dying branch was a swelling of the stem. I also notice dead branches on 3 other hazelnut plants.

There was a D shaped hole just below the enlarged area of the branch.

I shaved off the bark and found that a bark borer had girdled the branch causing the upper part of the branch to die.

I pruned out the dead branches and found the D shape hole in all the branches.

I contacted the Northern MN Hazelnut Cluster group and Brian Aukema, the forest entomologist at the U of M, responded with this information.

Brian Aukema                         Fri, Jul 30, 4:38 PM

NORTHERN_MN_HAZELNUT_CLUSTER

Yes, we've noticed increased borer activity this year and have been looking into it. These are native Agrilus beetles (same genus as Emerald Ash Borer) that leave D-shaped exit holes in the stems, usually slightly above cracked stem swellings. 

One our technicians, Patrick, has been working with Hailey Shanovich this summer (both copied) and provided this little summary:

"There are at least two species that use hazel as a larval host in our area. The beetle we've been seeing in large numbers is Agrilus pseudocoryli, a species for which there is very little published information. Adult beetles emerge in late spring to early summer - we saw the largest emergence this year around the second week of June in St. Paul and Rosemount. We have noticed the exit holes on a substantial number of dying branches this year."

We are working on quantifying the extent.  We did a small feeding assay in the lab, but do not think the adult feeding contributes to branch decline.  I'm sure the drought has exacerbated this problem.

I would like to thank the Northern MN Hazelnut Cluster group, Brian Aukema, Lois Braun, and Greg Schwese for their help in identifying this pest.

Not only where their dead branches on the plants, but Japanese Beetles as well.

As you can see they do a good job stripping the leaves.

I'm glad the borer and Japanese Beetles have not made it to my orchard in North Dakota, but I know they're probably moving this way.

One pest I do have is the Hazelnut weevil. 

I finally got a good picture of a adult weevil and sent samples to Patrick Beauzay, NDSU Research Specialist, Extension Entomology, who identified the adult weevil as Curculio obtusus, a species that is common on hazelnuts in the eastern U.S. and less common as far west as eastern Manitoba and eastern North Dakota.

This is the larva of the weevil emerging from the hazelnut after the nut was cracked.

This picture was taken on the 6th of August. I had no idea they emerged from the nut so early.

This year the weevil larva has emerged early before I could pick the nuts.  I count on controlling the weevil by picking the nuts as early as possible and catching them in trays on my drying racks. This technique may not work anymore if the weevil larva as already left the nut a week before they're picked. 

I might have to look into other options for controlling this pest.  

This is another type of weevil identified by Pat Beauzay as a Green Immigrant Leaf Weevil. The adult green weevils feed on leaves and the larvae feed on roots.

I think they may be damaging the immature nuts when they're small because I found them inside the husk next to a damaged nut. I also found  many of them hiding in the husk next to the mature nuts.

Early squirrel damage

I was surprised to see so much squirrel damage this early until I checked the hazelnut plant and found some were ready to be picked. 

Here is my first plant that I harvested which is a week earlier than last year.

I think it was either due to the early warm weather this spring or this year's hot dry summer.

I estimate the squirrels removed about half the nuts before I got there.

Here I am picking hazelnuts and trying to stay ahead of the squirrels.

This is a close up of the hazelnut cluster. Before picking the cluster of nuts I always make sure the nut rolls easily out of the husk. Just below my hand are the catkins developing which will pollinate next years crop in the spring.

This is a close up of the catkins (male flowers). I pay close attention to their location and try not to remove them when picking the hazelnuts.

 

Here I'm showing the general height of this hazelnut plant. This plant may be about 20 ft tall. 

This is the base of that same plant. I plan on removing the center stems, because they have started to produce smaller and less nuts than the stems on the outer portion of the plant. 

Could it be possible that the outside stems are girdling the center stems?

Different types of hazelnut husks (involucre)

This one has a long leafy inclosed husk almost like a Beaked Hazelnut.

This one has more of an open leafy husk and it's one of my best plants with a large nut that separates easily form the husk.

This one has more of a thick juicy husk that is hard to dry down and it tends to dry around the nut making it hard to separate the husk form the nut.  

Here we have a husk that almost aways stays on the plant and the nut will just fall out when ripe. These are similar to the European Hazelnuts that are swept off the ground.

 

This is another one of my better plants with a large nut that separates easily from the husk.

The husk here is from a wild American Hazelnut which drys around the nut and the husk has to be pealed away from the nut which is a little tough on the fingers. 

This is one I prefer not to pick and the squirrels will not usually touch these until all the other hazelnuts are gone. 

Here is another open husk in which the nut easily drops out.

The husk here is one that tends to dry around the nut but is easier to remove in the mechanical separator.

This one has a smaller nut that drops out of the leafy husk.

On this plant I lay a tarp down and shake each stem. The ones left on the plant I remove by hand.

This is the one I hate the most with the small sticky hairs on the outside of the husk and when dried down the husk becomes a hard covering. This is one the squirrels will not touch and when dry the squirrels burry the whole husk and nut.

Another harvest under way for 2021.

The green house, aka drying shed, makes a safe place away from all the pests to dry down hazelnut clusters.

 

Hazels in Willamette Valley Oregon

While visiting our daughter in Corvallis, Oregon in the first week in March, we toured some of Oregon State University's greenhouses and test plots.  I found it very interesting, especially the hazelnut plant research, and thought it would be interesting to show some of the things we've seen on our trip. 

 Oregon State University

 

We first toured the hazelnut test plots that OSU uses for testing their fruit and nut trees. This picture is of the older hazelnuts, which are most all identical clones. Because hazelnut plants are not self pollinating, they need a different cultivar to pollinate the cloned plants.  The pollinator is painted white which is on the right in this picture. There are also a pollinators on every 5th plant in the same row. All of these hazelnuts are in full bloom with pollinator producing large amounts of pollen.

Right beside the hazelnuts where these apple or cherry trees pruned to about 5 or 6 feet high.

I was surprised they pruned them so low.  If my apple trees where pruned that low the deer would have nipped the new branches and eaten the apples.  I'm wondering if they even have deer in the area.  

In this picture the hazelnut plants were planted about 2 feet apart. I was told they were going to be dug up and used for bare root planting.

What have they done to these hazelnuts? 

As I looked closer I realized they were mound layering these plants to clone them. It looks like they just removed all the layered suckers. 

This  green house was filled with this plant. Can you guess what it is?

Here is another look at the hemp that they were growing. Some of these plants were almost 10 ft high.

I don't think I could work in this greenhouse because the heavy smell from the hemp.

I just could not believe at all the new hazelnut plantings in the area. 

In this picture the hazels are in full flower and have just been pruned.

I'm guessing these hazelnut trees here are about 3 years old and about half are flowering.

 

In this field I could believe how large these new planting are, the row must be about a mile long because I could not see the end of the rows.

I noticed some of the trunks painted white to indicated that they must be the trees used to pollinate the rest of the field.

Here you can see the ground is yellow from all the pollen being shed from the hazelnut plants.

I just happened to bring some of the pollen back with me to try to pollenate some to my hazelnut plants.  I just wish I knew what cultivars they are.

This is an older field of hazels. I just couldn't believe how flat and weed free the ground is.  

It just didn't look right with no ground cover, but in a commercial operation you need it to look like this if the nuts are going to be swept off the ground.

North Dakota Hazelnuts

Back home in North Dakota, my hazelnuts just started blooming on 20th of March which is really early. It's usually been about the first week in April.  I also hand pollinated these with the Oregon pollen, and hoping for some Oregon crosses.

 

Here is a 2 year old clone that was flowering and should produce nuts this year.

Here is that same clone with the catkins (male flowers) and the red stigmas (female flowers) at the end of the buds. These were also pollenated with Oregon hazelnuts.

These are some the new plants that were stratified and just germinated on the 21 of March.

Now we wait to see how the plants overwintered, work on germinating more seedlings, and transfer plants to the greenhouse for spring.

 

 

 

Winter 2020 Hazelnut Coppicing

Culling the Orchard

We had an exceptionally warm fall this year, which gave me time to cut down and start removing some of the inferior hazelnut plants.  Most of these plants had small, thick shelled, or bad tasting nuts and other plants suckered badly or had EFB (Eastern Filbert Blight). 

All the plants you see above are resistant to EFB.

 

I originally thought it would give more spacing for the better plants, but found that some of these plants were still in groups too close to each other. I prefer 5 ft spacing with 8 to 10 ft between rows, but because of limited space I plant them a little closer. 

As you can see in this picture I have some large open areas that will have to be filled with some of my better hazelnut plants.

These are about 120 plants that were cut down.

To eliminate suckers from coming up from the stump next spring, a herbicide is painted on the stump and then covered with soil. 

The plant stems that I found this year that were infected with EFB where burned immediately to help reduce the spread of the fungus. The green branches didn't burn very well so I had to add some dry ash logs which did the trick. 

Eastern Filbert Blight

The other pictures looked so black and white so I thought some color pictures would look nice and I could explain a little bit about EFB.

In the spring the fungus first infects young new shoots, but does not show up visibly on the branch for the first year. Sometimes I can spot an infected stem in the fall by a flat spot on the stem and a brown color in the flat area when the bark is removed. The picture above is a two year old stem and starting to show the tell tale black cankers in a row going up the stem.

I try to remove the infected stems as soon as possible to reduce the spores infecting other plants.

This plant had EFB for about 5 years before I spotted it. 

Some plants produce good nuts but are not resistant to EFB, so I prune any stem that is infected, and also remove all the catkins (male flowers).  The catkins are removed to limit the plant passing on its        non-resistance to EFB.

Here is a close up of an infected branch that is 3 years old.

If Eastern Filbert Blight is not pruned out every year the hazelnut plant will look like this in 10 years.

Right now there is no fungicide to slow down or kill the fungus so removing the plant with no resistance to EFB or pruning is the only option.

I've started training the new cat to hunt squirrels, but so far he hasn't been able to climb as fast as the squirrels. I wonder if a mink would do a better job.

Here's to a good hazelnut crop this year!!

Hope everyone has a happy and safe 2021:)

Great Fall Colors, 2020

 Fall 2020

This year the fall colors on the hazelnuts were better than I've ever seen. With this unusually mild fall the orchard showed its best colors.

In this picture you can see that some hazelnut plants have turned a nice red color. Who needs maples when you can have a bright red hazelnut that also produce tasty nuts.

In the next pictures you can see every plant has a little different coloring

 

These hazelnuts are the some of the wild plants from southern North Dakota by Lisbon. This is one plant with many small stems and lots of suckers.  

This plant with some nice color is a hybrid with few suckers and  nice structure.

This is a 4 year old new hybrid with one trunk.  It will be interesting to find out what type of nuts it will have next year. I'm hoping for large, thin shelled nuts.

This is another new hazelnut plant that had one major trunk, but was badly damage from rabbits last winter. All the branches above 2 feet where damaged and had to be pruned. This plant recovered with over 3 feet of new growth, but it produced 2 suckers which might have to be pruned off. It also lost all the mature stems that would have produced nuts for next year, so with a little pruning it will be producing nuts again in 2 years.

This is a 15 year old plant that has a nice structure with 5 stems and produces large nuts. The small stem to the right is a new stem that I'm cloning by layering. Next spring I'll remove it from the mother plant if it has a sufficient root system and pot it up. I'll leave it for another year if it has a limited root system. I have found that some types of hazelnuts take 2 years to produce sufficient roots before it can be remove from the mother plant.

This year we had a very poor crop of hazelnuts, but in late summer the plants have produced an over abundance of catkins, which is the male flower that will open in the spring and release pollen for next year's crop. I'm hoping this is an indication of a big crop for next year.

Problems in 2020

The beavers have been busy this year. This is not a hazelnut plant but a Boxelder tree and close to a row of hazelnuts.

Here is that row of hazelnuts with what is left of an oak tree in the bottom of the picture.

A few years ago a beaver did major damage to a row of hazelnuts and now any hazelnuts close to the river are fenced.  So if you are planting along a river you must protect your nuts.

This year I thought there wasn't any deer damage but I was wrong.

These next pictures are more damage from a buck who thought he'd let me know he's back.

Fall colors in my back yard where also spectacular this year.

It sure as been an unusual fall.