Betula nigra, the river birch, is a very common shade tree in the Midwest. This is especially so since the introduction in 1979 and gradual recognition of the Heritage River birch cultivar (Betula nigra ‘Cully’), which culminated in it winning the 2002 Urban Tree of the Year award as determined by responses to an annual survey in arborist magazine City Trees. This magazine serves as Journal to The Society of Municipal Arborists (SMA) and it’s readers select a new tree to honor each year.
The three most common birch species grown in urban environments in America are paper birch, European white birch, and the heat-tolerant river birch. River Birch, or Betula nigra, seems to be the only birch truly adapted to the hardships of urban conditions. It is also the only one that is resistant if not practically immune to the bronze birch borer, a scourge of white-barked birches.
Dwarf River birches for urban settings
While river birches are some of the best birches for urban settings, they are also LARGE trees often reaching 40 to 70 feet high. This makes them a bit large for a lot of garden uses. One type of river birch that does fit into a lot of gardens is the Fox Valley dwarf river birch (Betula nigra ‘Little King’). This tree was discovered and introduced in the late 1970’s by Jim King of Oswego, IL and in 1991 promoted through the Chicagoland Grows program. It is a dense compact growing tree with great exfoliating bark that only grows to 10 to 12 feet after 15 years or so.
This dwarf river birch can grow into a dense shrub-like form that so effectively blocks out light that the entire inside “dies out.” That is how this one appeared before I thinned it, as exhibited by this photo.
As you can see in the photo about, in the summer you cannot even see past the outer shell of the plant to its attractive exfoliating bark.
Pruning the dwarf river birch
By selectively removing branches from each of the five main trunks, I was able to quickly thin out the canopy.
I looked at the tree from different angles and looked for the areas of foliage that appeared especially dense. I then went back to these areas and thinned some more branches out. I then looked at the plant again and this time from the outside of the tree, selectively thinned out the clumps of whorls of branches. This was so that instead of 6 small branches occupying an area, only 2 or 3 did. These were much smaller branches I was cutting, perhaps only ¼” thick.
When pruning birches including dwarf river birches, it is best to avoid Spring and Fall pruning when the sap is flowing as this will stain the branches and trunks by “bleeding” sap.
A late August or early September pruning is probably best as the leaves have produced most of the energy for the tree that they will produce and the hottest most stressful part of summer is past.
Pruning load is the percentage of foliage that is removed from a tree during a pruning session. Some trees can handle a larger pruning load than others. Birches are sensitive trees. Therefore, I limited the pruning load to 15-20% for this session.
Conventional standards recommend no more than 25% of the foliage to be removed, but at Anderson Japanese Gardens where I work, we routinely remove 50% to upwards of 70% of a tree’s foliage with no ill effects.
Keep in mind those trees have been trained every year since they have been planted and have adapted to this level of pruning. They are also not 70 foot high shade trees. But instead have been kept for the most part under 25 feet, so they do not have the structural requirements of a large shade tree.
While this dwarf river birch was not heavily trained as would occur in a Japanese garden, by exposing more of the exfoliating bark and also opening up the canopy to allow more light to shine into the tree’s interior, I think this subtle pruning resulted in a nicer looking and healthier tree. What do you think?
For more information on this dwarf river birch see http://www.chicagolandgrows.org/downloads/foxvalleyriverbirch.pdf
If you have some pruning in your future, you might want to subscribe to my posts to get a copy of the Eight Gardening Tools I Can’t Live Without.
Steve ulmer says
Ordered river birch from moon valley for fall planting, region 8b, it has 4 or 5 trunks. The plan is to put it near our butterfly garden as a host tree. I’m reading they are very messy and require a lot of cleaning up after, is that true? Does a dwarf river birch do both, host and less mess? I have a mature red oak that also helps with butterfly’s.
Yes, large River birch are a tad messy dropping small twigs. I never found Little King to have this problem.
I have a 4 foot strip in which I hope to plant one of these…can it be pruned to be only 4′ wide or will that eventually kill it? It can’t go beyond 4′ as that will then block my neighbors driveway.
How about this plan: can it be trimmed up on the bottom to resemble a tree rather than a shrub to the extent of clearing an SUV..e.g. so the car can drive under?
It can be limbed up but will never get tall enough to look decent doing that.
Bruce Dobson says
I have a beautiful little king river birch. It is about 15′ tall. My problem is I noticed that yellow leaves started falling off it is the end of june. Come to find out there are two birch trees around the corner with NO leaves on them. I started cutting the branches of my tree that looked bad. I did not know that you cant cut the branches til sept..
I never had the top canopy trimmed. Is my tree done. Any way to save it?
Mary bartman says
We live in Columbus Ohio. Have contacted most all nurseries in our area but none carry the dwarf river birch. Where can I purchase one.
Mark Thompson says
Jim – Great site…thanks for all the info. I live near D.C. and would like to plant a Fox Valley birch on my patio in a container. If that is possible, what size container should I use, assuming I want it for a decade or more? It gets morning and early afternoon sun. Thanks for any guidance.
Jeanette caleca says
Just bought one of these beauties today and so looking forward to planting near my water feature! Thanks so much for posting all the tips and the pruning tip is just the best
Richard Eastman says
We have two matching Dwarf River Birches. After a long winter , both sprouted well this Spring. However, one is showing strong signs of wilting. We are in Northern NH and have had the driest Month of May in 40 years. The new growth is looking as is it is wilting and there are even brown curled leaves on it. Looking at the leaves, they appear to have lines in them. Another problem is that the past two years, the leaves had pimply growths on them. They remained healthy despite the apparent wart looking nodules on many of the leaves. Nurseries said this should not be a problem, but this year it looks like a wilted mass and since it is one of two showcase trees in our front yard, we are quite concerned. I would appreciate your thoughts. You can email me at firstname.lastname@example.org. Thank you Richard Eastman
It does sound like drought stress and maybe something else. Did you water them during the May drought at all?
Kathy Darr says
Jim, We had a little king river birch planted last fall and now it doesn’t look very well. There are some
leaves on the tree but a lot of it is bare. The place we purchased said it was 30 years old and it
would be beautiful. Do you think we made a mistake? Please help me as this is the beginning of spring
here in North Carolina and maybe I am rushing the tree to grow the pretty green leaves.
Thanks a bunch,
I have no idea. I have snow on the ground here and hardly a leaf on a tree.
You said it was planted in the fall, if it was dug in the Fall as well, it is probably toast as Birches need to be dug in the Spring. If it was dug in the Spring and just not planted until Fall it should be OK.
I have a hard time believing it was 30 Years old. If it was, it must be very large (for it being a dwarf) and probably had massive transplant shock.
The only thing to do now is take care of it with regular watering and see how it does.
Nancy Bonoli says
Love your article. I bought a little king 2 years ago and it didn’t do well the first year. I didnt give up on it, did some orining in Sept and this year WOW! I wsnt to trim the lower limbs to expose the trunksand bark. I will wait a few of weeks. I am in Quincy MA
Sally Fenton says
Thanks for the article and the blog post responses, it’s all helpful. We are in Western Massachusetts and have a 7 year old dwarf river birch that is about 10′ tall. It is a beauty! The challenge is that the birch is the centerpiece in a fron yard landscape and is crowding out some French lilacs. I am thinking that I would like to bring up the canopy in order to let the lilacs have some sun and air. Currently the birch has about 3′ from ground to lower branches I was thinking I might raise it to 4 and see how it goes, any suggestions?
You can certainly raise the canopy like you described, I did the same thing on mine many years after this blog post.
Charles Wood says
Hi – nice article on pruning this lovely dwarf. In reading this, it seems it likes moist roots. I have a low spot that can get pretty soggy – standing water much of the spring (Iowa). Would you recommend this species for such a wet location or maybe a little higher ground?
Yes I thnk it would like that spot assuming it gets enough sun.
Charles wood says
Geat, full sun, maybe a little shade in the morning. Thanks!
Thanks Jim……I believe that Birches are beautiful trees and still like them but just wanted to make people aware of some of the issues that individuals may be confronted with these trees (because of their extensive root systems) when they are planted/grown near driveways, parking lots, sidewalks, sewer lines, septic lines, foundations etc. It can end up being a costly mistake and the tree ending up being taken down. It is always important size any tree correctly – make sure that there is plenty of space for it when it reaches maturity. I like to size on error too. I have cultivar (grafted) Japanese Maple – “Pixie” which is “supposed” grow only 6-8 ft. The one that I planted next to my house as a dwarf tree/bush has now 16ft tall and is still growing. It has used all the space up….I did not expect it to grow that big. It is in very advantageous micro climate, full sun, well drained rich soil, shielded from the cold northern winds by the house. It is 3 times the size of other Pixie, I have planted in the front which is actually 2 years older……amazing.
Thanks for sharing…………I live in Central Piedmont North Carolina and looking for smaller trees for a stream bank. Birches love water. How big have you seen these “dwarfs” get? We had a River Birch at our last home, it was a beautiful tree. I did not care that it was “sappy” and shed a lot leaves during the hot summers here. It had to be cut down because this was a townhome community and where it was planted was the wrong place. The non- dwarf birches can grow more than 100 ft tall with large root systems. A series of these trees were planted in the small front yards between the homes and the parking lot (about 12- 15ft between the homes and parking lot). They soon grew too large……they started cracking the side walks and when one crushed the sewer line for one of the units…..they all had to go…..$1500 to replace the line ….because of their root systems it would be only a matter time before the other units would have the same experience. I did not care either for all the sap and leaves on the cars. Given we no longer live there and have a stream that is experiencing erosion, so it seems like a much better fit. I do not want a large tree – nothing over 30 ft. 10-15 ft mature height being ideal. I would guess that they could handle the summers if the river birch can. My other concern, is the Birches tend to attract bugs….especially aphids. Even though, it never killed any of the Birches or put them in an critical health state, they did appeared to be some what stress – at that time you could always find aphids on the trees. What do you think? Not to sound negative…. What are the “Cons” to this tree? Thanks for your time.
The height of this tree will work for it, it will never get that big. It will have all the same pests as normal river birch, so aphids may be a problem if they have been on other river birch in your area.
Peter Sorl says
Hello: It’s great to find your site with so much attention paid to this beautiful tree. We have it in front of our house. Full southern sun in the Toronto, Canada area. Planted this spring May 2016. It’s quite young and came from a 15 gallon pot. It’s about 4 feet tall. We received from a reputable nursery. It came with very small leaves all over it. Very even looking and nice. Over several weeks, we noticed rapid new growth in some parts of it. Very green, large leaves. However, the rest of the leaves, the original ones, now have more of a crispy brown edge on all of them and they remain very small. And slightly curled. None have fallen. This looks odd. But is it normal and healthy? We give it a good deep watering with a drip hose every 5-6 days. I imagine this will sort itself out next year. Thanks in advance for your comments. I have links below in case you are able to take a look at a few pictures of our tree.
I think this is weather and moisture related, but who knows sometimes plants just do odd things. I think you are correct in thinking it will probably grow normally next year.
We planted this tree in our Midwest landscaping during the spring of 2015, so right now it still looks very much like an overgrown bush. Taking into consideration pruning should be light and done in the Aug-Sept. time frame, how old should the tree be before we start shaping it? Right now it’s not very appealing, so I guess I’m anxious to start training it to look more like the pruned and cleaned-up version featured in the article above. When I do prune the first time, do I need to be careful not to go too high? Would doing so ruin the look of the tree as it ages? Thank you for your help and advice.
Yep they are definitely bushes in their early years. Patience will be rewarded.
You should definitely NOT prune it up too high. Start raising it up slowly and try to leave some branches lower.
It’s a lot easier to take more off later then to get branches to regrow where you chopped them off. I think Opening the canopy a bit to let some light shine into the inside canopy and branches is a key to getting the most out of these.
In short, take it slow, get your feet wet and expect you will gradually be pruning more as the tree needs more. You can just enjoy it as a big bush right now, content all those little branches are growing nice attractive trunk that you will show off in a few years. I didn’t prune my Fox Valley River Birch much for probably 5 or 6 years.
Would this species grow in North Georgia? And if so, where would I find one?
Good question. Dura heat is the best of the larger river birches for the south. Not sure about Fox Valley. Call around to your larger nurseries and you might find one that carries it. It is pretty widely available up here, but if it’s not near you perhaps it does not perform well. You could always try mail order. Forest farm carries it I am sure, but it will be small.
Forgot to mention I live in Aurora IL.
It’s a small world. That tree probably feels right at home.
Very helpful post! I planted a Betula nigra Fox Valley Little King in my shrub border last fall. It’s about 4.5 ft high. Haven’t done any pruning yet…wanted to get it established first.
Is November an OK time to prune this tree or would it be best to wait til next August/September?
Thank you. Enjoy your website very much.
I would wait.
Lorna Sherman says
I just noticed my dwarf River birch is not looking as well. Some of the leaves look eaten, some are coming in brittle, and some inside are turning yellow….. I love this tree. What should I do ???
Don’t panic. Give it a good supplemental watering weekly at least if you don’t get any rain. River birch’s will have some of their leaves turn yellow and drop in the Summer, it’s common and not a big deal, it’s just something they do.
If you are in Japanese Beetle territory, you will have some feeding. Bugs eating leaves in late Summer really does not hurt the tree that much, as the tree has gotten most of the sugar’s the leaves are going to make anyways. A defoliation in early Summer or Spring is more harmful to the tree.
Pat Hines says
Where can I purchase a Betula migrant ”Little King”?
I am not sure where you are located, but this can be found in nurseries. I would call now and perhaps they can order you one from their wholesalers if they don’t carry.
Sylvia Manning says
I have been searching for a dwarf river birch and the description given for “Little King River Birch.is exactly what I need for a small area. I have been unable to locate one in my area. Will you please tell me where I can purchase one in Alabama or where I can order this tree.
You should go to a larger nursery in your area and ask them if they can get it. Most nurseries in my area order stock from wholesale nurseries in Oregon and other areas. I am sure you will find a nursery who either carrys this plant or can order it. River birch should only be dug out of the ground in Spring though, so you may have to wait till next year unless they have pre dug plants or plants in containers.
The other choice would be too order it through mail order, but that will get you a much smaller plant. GOOGLE Forrest Farm for one mail order nursery that carries it.
Lorna Sherman says
Thank you so much for your prompt reply. And no, I don’t live in Minnesota, I live in southern Massachusettes.. I m a little impatient but I will try to wait until August.
I just bought a Little King River Birch and am anxious to trim it. Can I do a little now without bleeding ?
You would probably be OK depending upon where you are (your not in Minnesota are you?), but I would wait till late Summer.
Pruning of birch trees should NOT be done between May and the beginning of August. It has been shown that female birch borers are attracted to fresh pruning wounds and that is the time they are flying around. River birch is pretty resistant, but I don’t believe it is immune to Bronze Birch Borer (the main enemy of white barked birches).
Also go light on the pruning, ideally less than 20% of the tree pruned off.
Kurt Oehlberg says
Very good article on pruning Fox River Birch. I have two to do this year. Is it acceptable to prune them late winter (before sap flows)? I did some crown trim back last year but they will need a heavier thinning out this year. I’d hate to have to wait til August-Sept. Appreciate any guidance. Many thanks.
Kurt you will get some “bleeding” so I would minimize the size of your cuts in the winter. I would try to wait till summer for most of your pruning.
Finally found this article after spending a couple of hours trying to figure out how to save my specimen, planted too near a chain-link fence. Now I think I can do it. Thanks a lot!
Glad you found it. Take a look at some of my other pruning articles for more guidance.
Stumbled on your blog researching this river birch. Your post helped me see that this could be the right tree for my yard and seeing it pruned really helps. Thank you!
I am glad I could help. It is a great tree for residential gardens.