Current recommendations for street trees

In my part of the country, Acer truncatum is very seldom used, virtually unheard of.

As I have got a few growing from seeds, now I'm concerned. Is Acer truncatum behaving badly anywhere in the states, or the world, for that matter?

I know of an Acer ginnala growing on a property nearby, and have reports of this being invasive. And, while I do see an annual flush of seedlings coming up in the mulch ringing the tree, I have never seen so much as a single seedling in the extensive woods and open ground around the home. I'm wondering if I would if there weren't way too many deer on the property?

Scott

I have seen no volunteers here at our place from A. truncatum, and not all that many from A. platanoides, but we are always fighting A. ginnala and sometimes A. campestre.

Our worst woody weeds are all shrubs -- Lonicera maackii, Elaeagnus umbelata, and Rosa multiflora, in that order. The Lonicera just jumped from #3 to #1 this past year, so things evolve and change with time. We don't even have serious buckthorn problems here, like they do up around Chicago, but someday we might. Kalopanax ranks fourth here, and is the worst tree-sized pest.

But move a few counties up or down, and it's a different pallette of problems. Everything is regional.

Guy S.

Guy, yes I have to agree everything seems to be regional. I have grown A. ginnala for about 10 years in my shrub border, and no problems. But the whole border is mulched quite heavily with wood chips to prevent weeds.

I was wondering what problems might be encountered trying to grow Betula nigra 'Heritage birch' as a street tree.

DonnaS

I would say that the problem might be droopy branches as the tree grows. You might have to prune them up to have room on the sideway for for parking cars. SB

The City of Minneapolis has used River Birch quite successfully as a street tree. I think they're probably 'Heritage' based on the attractive salmon bark color, but I'm not certain of this. I don't think anything can match the beauty of a street lined with mature American Elms, but the River Birch I've seen lining streets in Minneapolis made for an impressive sight. They were around 30' tall and grown as single stem trees.

Now there's an idea for physical diversity we don't see enough of. Thinking out of the box and using normally clumped trees as singles and singles as clumps. Does clumping normally single trees cause them to grow differently from competition? Ken

Might be challenging for single stems to be companion planted in close proximity to produce the aesthetic look you want but I don't see why River Birch couldn't be pruned back to a single stem. We have some plantings of River Birch around here and with the advent of the computer and kids preferring to stay inside these days fixated on their brain drain x boxes and such... I don't notice half the peeling of bark by unsupervised children that I would have seen just 10 years ago. There are some River Birch that have had their bark peeled that were planted at the entrance to the Bass Pro Shops at Gurnee Mills but those seem to be withstanding the abuse quite nicely. The River Birch are very nice trees.

As far as Elms, I would agree. In Lake Forest IL we still have some American Elms left standing and they are absolutely magnificent. My husband said when he was growing up that the streets of his neighborhoods were lined with them. I'd seriously consider checking into some of the DED resistant Elms as that was a great suggestion.

Having had fortune touch me by blowing river birch seeds into the seedpots of stuff that either died or never came up, I can report that river birches are naturally single-stemmed--at least the vast majority of them. The clump form is an artiface of the nursery, I suspect, to make them grow more like the paper birches everybody would rather grow but can't.

Scott

Hi Scott - same applies to Paper Birch too. They're not naturally multistemmed, either. The clumps in gardens are similarly deliberately engineered, and any clumps in the wild are regrowth from stumps after cutting or browsing (by deer, beavers, people, road crews, etc)

Resin

Alright, having knee surgery means never having to say you're sorry.

I seem to be a half-day late and a dollar (£0.562 and €0.823) short to the river birch (Betula nigra) habit discussion.

Working amongst native river birch, and having admired many mature single trunk plants around Louisville parks and elsewhere, I've wondered what people see in the multi-stems (other than more bark). As Resin and Procumbent have stated, the extra stems are created on purpose as a marketing device (obviously plenty of takers willing to part with their cash) and are otherwise superfluous suckers unsliced.

DonnaS: The issues with river birch will probably be cultural. This is typically a lowland to wetland type species, which more often inhabits soils on the acid side of neutral. Doesn't mean you can't grow it elsewhere; just be aware of it's tendencies. On a more positive note, it is such a vigorous grower (and it is always in surplus in nurseries around here, for give-away prices) that you could actually afford some trial and error with it. It would be worth a shout to Minneapolis to find out how they constructed their planting sites to allow for the success related by Maackia.

If you want to wait, I'll ask myself as I may get up there for the ASLA conference in October.

Hi Donna you are a busy person. I'll keep it short. A 30 to 40' tall very columnar Aspen is the Swedish Aspen. Not to prone in my garden to have runners (after 5 yrs) Also it has beautiful golden red/green new growth and deep green Summer growth and beautiful Aspen yellow fall color. Great shape in winter with branchs. See pictures. I also like my European Hornbeam. Not as pretty with colors.

Nice tree. Great shape. Everything here has either a full skirt:
conifers, or a vase shape: clump maple and basswood predominate. Some single stalks, probably what the cut-over crew did not want. Have to protect from the beaver though.

What does everyone think about the Freeman maple hybrids? They're recommended as a replacement for green ash. They are pretty to look at, but I wonder if they are going to be as weak wooded as thier silver maple parent.

Thanks everybody. I have been doing a lot of googling. We (the four of us from gc on the tree board) are having a meeting next Tues. to try to narrow down our prospects for street trees in this normally very dry area.

Soferdig, I am wondering how the aspen would perform in the middle of a sidewalk in the summer time. I have myself only had contact with the native aspen, which I like except for the root runner aspect.. Loved your photo.

escambiaguy, I will see what info I can get googling the Freeman maple hyb.

DonnaS

Hi
I did landscaping for buildings being built in NYC.
One of the more memorable ones is on 54th and Madison,
and I had nice Gingko's put in. this was about 30 years
ago, before anyone knew what a gingko was.

Aspens are short lived. Be careful.

I also used weeping trees a lot. And then did them bonsai style
or cut off the trailing stems so they all looked like umbrellas.
Outstanding!!!!

Some folks were recommending too tall trees. You said you
had to be careful of power lines. I shudder to see poor pinus
sliced down the middle to accomodate the stupid power lines.
And the big honkin sugar maples with half of their crowns gone.

There are a few Elms being grown now by the Botony shop.
they have survived the Dutch Elm and have reproduced. They
have some of the 100 footers and then they also have some
that are about 40 footers. the National Arboreteum has grown
these and they are doing well.

Hope this helps too.
Regards,
sheri and plantanus

I had a chance to look at the River Birch over in Minneapolis and thought I'd share a pic of them. They're planted on about a 10-block stretch and all seem to be doing well. Surprisingly, no indication of vandalism.

Thanks for the photo Maackia, they really look good. I presume the downtown climate there would be similiar to here. My River Birch does very nicely here in my yard, but I don't know how the heat reflection from sidewalk and street would affect looks and growth in a city situation. Thanks for your help

DonnaS

I can't see using River Birch as a street tree. As the owner of two 35 year monsters, I can attest to their tendency to drop limbs by the bucketful. They shed a lot of branches throughout the year, and seed out like crazy in my woods. They are also very prone to chlorosis around here in many yards, AND they don't call them RIVER birch for nuthin'! They suffer around here when not getting they water they desire.

Kevin, thanks for your input. I guess because conditions are different here, my Heritage River Birch doesn't drop limbs and I have never seen many seeds and no seedlings. But I still wonder about it being a good street tree.

DonnaS

I still think the best street tree is a different one at every house. Just keep in mind your priorities (no heavy or messy fruit dropping on cars, no cascading lower limbs to block visibility, no thorns at eye level, no invasive propensity, no serious epidemic diseases, no soil/climate problems, etc.) First weed out the obviously problematic ones, then mix things up. Try a few of the birches, but don't bet your lunch on them (or on any monoculture). Diversity is a good thing.

Guy S.

Guy S, thanks for your help. We are only planting trees in the small downtown area, probably if we are lucky to find available money, only the two main blocks . A large, and only hardware type store burned completely last Easter sunday. It was located in the middle of downtown Tonasket. the owner is rebuilding, and just finishing the shell or outside of building now. Hopes to be open for bushiness by the end of April. He is going to plant 6 trees at his expense on the corner, 3 each side. So at our last meeting we gave him our suggestions as to the 6 trees he will plant this spring. Our sug. were Patmore Ash, Spring Snowflake Crabapple andChanticleer Pear (against my objection). So we will see what happens there. I doubt if any more will be planted this year as haven't gotten the ordnance passed by city council.

DonnaS

Would Sassafras make a good street tree? They have nice fall color.

The national champion sassafras is a street tree in Owensboro, Kentucky. It has no thorns, no fruit problem (male tree), erect sympodial branching, strong central leader, pleasant aroma, no pathogens of consequence, and tolerates poor soil. The species does tend to sucker a little (more if disturbed) and occasionally will drop some limbs in heavy storms. Sounds promising though, especially in the Southeast and Midwest where it is native, if you can find nurseries that grow it.

Guy S.