Do they make nuts? Do you want nuts? Are the plants otherwise good in your landscape? The answers would dictate how many suckers to prune.

They make good nuts, but not many in the last years. The nuts grow on the previous year's wood, which is why they should be pruned.

Most of the nuts seem to be clustered at the top of the tree (about 15' high) if the birds are any indication. And I don't see much on the ground (the birds know to leave the ones with no meats).

Sue

In most cases, I consider small Hazelnut plants a nuisance weed in the garden. Large ones are hard to remove. I've used a bulldozer on them a number of times.
They don't seem worth the effort to harvest the nuts. A lot of them are infested with worms.
They take up a lot of room, and the Fall color and branching pattern is nothing to brag about. In short, they don't earn their keep.
I'm sure some others have a different opinion and circumstances.
Mike

I must not have been clear in my original message.

I do not want opinions on whether or not to keep them, I want info on how to deal with the overgrowth, if such a solution exists.

Sue

I guess you could walk around them and cut off anything that is hanging in your way.
Are they growing out over the driveway, sidewalk, or lawn?
My solution on how to get rid of the 'overgrowth' is to get rid of the Hazelnuts. Otherwise you'll be nibbling away at those suckers from here on out and there is usually not enough room to get a saw in close enough for a proper cut down low. Suckering is the nature of the beast. Why fight it?
Mike

This looks like it has some good information:

http://www.ehow.com/how_5078833_prune-hazelnut-trees.html

with aggressive pruning they can look great. orchard trees are pretty good looking. and if you like winter interest, man they look great in jan/feb.

my solution to this issue would be to remove the tree and start over. they grow decently fast.

i have a neighbor that has a poorly trained hazelnut, the bottom 2 feet are UGLY. just a mass of suckers that they cut off once a year.

Commercial orchards using commercial varieties are a whole 'nother ballgame. Those are trained as a tree right from the beginning. They sure look nice!
My wife has a relative with 20 acres of Hazelnuts in Gaston, Oregon.
Mike

Commercial orchards using commercial varieties are a whole 'nother ballgame. Those are trained as a tree right from the beginning. They sure look nice!
My wife has a relative with 20 acres of Hazelnuts in Gaston, Oregon.
Mike

totally agree, thats why my solution is to start over and get them trained young.

The original question seemed to have an obvious answer, that is why I probed for details.

If you want some nuts, prune off all but a half-dozen suckers and cut those way back so eventually you can have nuts closer to the ground. Keep any new suckers cut down.

Otherwise, you can't get rid of the plant by pruning, you have to resort to digging.
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My relatives had filbert acreage near Aurora, I grew up eating roasted, salted filberts in season. An old filbert orchard is spooky at night, as you can imagine from the above photo.

That's what he's looking for in the picture - to see where the spooks went.

I always thought summer pruning is what you do to control growth.
Pruning now after the leaves have sent all their food down into the roots contributes to even more water sprouts and suckers in the spring when there is not enough plant structure to use all that energy. ( Is that still the correct teaching or is there new research on this? anyone? )

What I would do is prune off only the parts that are most in your way now.
Then keep all suckers PULLED off while still young as they occur during the spring and summer.
Then really go at it in late August/ Sept and cut off most of what you don't want. ( you could take 2-3 years to do this if concerned about stressing the plant too much i.e. remove 1/3 each year)
Then keep at it with continuous young sucker removal.

I glanced at an orchard textbook at Half Price Books ~a few years ago and happened to see where it said studies had found that heading back in summer (instead of winter) didn't, in fact reduce the amount of sprouting. I haven't seen any additional, newer information on the subject but I haven't been looking.

'Mowing down' is essentially coppicing. It is the hazel's ability to regenerate after regular coppicing which was the basis of their importance to the UK landscape and economy for centuries. The resultant poles were a valuable crop used in many ways including weaving into wattle for building and fencing. So - no - mowing them won't control them. It will encourage them. If you would like to grow your own bean poles and plant stakes and provide valuable early nectar for the local bees hazel will do a good job. And nobody has mentioned the attractive catkins which are one of the very earliest wild flowers here. Some larger country gardens have attractive coppiced nut walks underplanted with early spring bulbs.

Here is a link that might be useful: Example of a nut walk

Yes, the filbert winter catkins are quite striking in Willamette Valley orchards.

If they get Eastern filbert blight and they're not resistant cultivars then you may end up taking them out for that reason.

Many Willamette Valley orchards have youngish trees for that very reason. That and the decline in grass seed production led to many acres converted to nuts.

It occurs to me that the preferred marketing term, hazelnut, has not found its way to the disease, filbert blight.

Ok, my suggestion may sound a little crazy, but bare with me.

I planted hazelnuts(2) when we first moved to our property, one other was already here.. All have nice trunks, but do sucker. Since yours are all suckers my guess is someone has already done the "chainsaw guy" thing and this is the result.

I would start selectively harvesting some of the whips until you have a size clump you want. Then I would braid and intertwine the outside suckers. They will grow together with an very interesting trunk formation over time. I have used the cut limbs for intertwined fencing over the years and it is very pretty. Only draw back is it rots relatively fast.

My three filberts have not been pruned, except to limb up to walk under or provide more sun for the shade garden under for the last ten years. (I used to prune them religiously, but....) They are each multi trucked and are a focal point in the yard. The trees got rave reviews at the engagement party held in the back yard a couple of years ago. They have a paths weaving around a variety of ferns, hellebores, pacific bleeding hearts, sweet woodruff and other woodland plants in their shade.

The catkins provide winter/early spring pollen and feed for the Anna's hummingbirds, and the nuts provide food for scrub and stellar jays. Of couse there are the squirrels too.

Good luck on your project. I love our filberts and hope you can get yours looking the way you want.