A Red Oak with extreme chlorosis in Toronto is indicative of highly compacted soils and/or a thin veneer of topsoil over subsoil (typical new development tactics). A less likely possibility (assumed), poor drainage.

Katsura prefers rich consistently moist well drained soils and is fairly drought intolerant. Probably not a good choice if you are having problems with a Red Oak.

Zelkova is more tolerant of adverse soil conditions however, unless you are south of the 401 or near the lake east or west, Zelkova can get cold damage in extremely cold winters. May not happen often but when it does.... In Kingston, Ontario, that winter seems to come every ~15-20 years judging by the Zelkova I've seen.

Consider Chinquapin Oak or Bur Oak if you want to stay with an Oak.

Some of the Elm varieties too...eg. Accolade, Prospector, & Frontier

Ginkgo

If you have Katsura growing already and they are happy, sounds like you'd be ok with another one. Personally, I'd stick with an oak...both Bur and Chinquapin are native oaks and will thrive in rocky limestone (alkaline) soils....or soils laced with limestone gravel.

Once established, Bur Oaks grow at a similar rate to Red Oak around here. Ditto for Chinquapin Oak. Chinquapin Oak is native to SW Ontario (Hamiliton to Windsor) and Prince Edward County to past Kingston.

My neighbor has a bur oak and it’s growing very fast. Correct placement and soil can go a long way. He may fertilize too. I wouldn’t doubt it. I know he does the lawn around it.

If you are open to something out of the box, check out the newer Ogon Zelkova. I planted two. They prefer full sun to maintain the yellow leaves, but the bark and branches are a vibrant orange, even fro afar. You may have to do mail order because they are new, but heck, they grow fast and if you are only doing one tree, might as well be something out of the ordinary.

Thats why I suggested mail order. Funny, but I have been meaning to squeeze in a Red Fox Katsura in my already crowded 2.5 acres. Have you experienced the burnt sugar fragrance or is it overstated? I have walked by them in a nursery, but experience even a whiff.

When does Katsura normally change to fall colour? Mine is on its second year and has been burned by hard frosts both times before changing colour...

"When does Katsura normally change to fall colour?"

You're still in Edmonton? In southern Ontario, it's a 'mid-season' tree. After the Maples but before the Oaks. Your transition from summer to frost/freeze is much more abrupt though, and is catching the out the Katsura. It's native range is much more similar to eastern NA where cooler temperatures prevail for weeks before a hard frost/freeze arrives.

Plant Love, your experience with Katsura (Cercidiphyllum japonicum) mirrors mine, and I think Smivies has it right about the seasonal transition.

I've tried this tree twice (once at each property), but neither lasted more than a few years. I keep thinking I just have to find the right microclimate, but I also suspect it may not be quite hardy enough for z4 WI. I'll probably try it again, but I'm less smitten with this tree than I once was.

I can't smell a thing on my Katsura's autumn leaves, tho they often just freeze dead/fall off without coloring in my frost-hollow. Otherwise it is a good tree.

Anyone else have the same experience as Beng? I maybe able to squeeze one in. But the fragrance would be a big plus in trying to decide.

Hmm, before oaks but after maples. Well it seems that where I live, there is no set time for change as all the different types change at completely different times. This is probably because we don’t have native maples and oaks and they are all different varieties that people have planted. To be honest, I feel like my problem has been the ridiculously early hard frosts the last two years. That being said, I’ve seen trees ”learn” to change earlier after getting burned off.

This happens a lot because we get trees from warmer climates like Washington and British columbia and the trees aren’t adjusted but they learn lots of the time after one bad year. Clearly not all of them learn though. This was the weirdest year I’ve ever seen. Coldest two weeks of September in history and yet the trees changed weeks later than a more normal year last year. And many trees didn’t even change and just burned.

Clearly there is more that makes trees change then just low temps.

Smilies: I moved from Edmonton to a colder zone northeast 200km and i bet you wouldn’t even believe It. The Katsura took -39 last year and only lost the tips where they burnt from the hard frost because they were brand new shoots. It was hands down the coldest winter I’ve ever seen and brutal spring till mid April.

This Katsura is unbelievably vigorous and put on a good 16” this year. It looks like everything hardened off except about 2” that burned. The terminal buds look nice and pink like they should.

My new autumn blaze pear has been the thoughest tree in my yard and is still completely green with some purples starting to show. We had -6c so far about 18f and most of the trees in my yard burned even the poplars and manitoba maples which is unbelievable.

Mackiia, what happened to yours again? Dieback every year? None of the wood that hardened off on mine died back. Honestly I have no clue how mine has done so well but I have lots of trees in my yard that should be dead and aren’t. I’ve watched many of these trees get trialed by nurseries and fail at all of them but mine are still trucking.

Might I add that they are not in protected locations. Full wind gets em.

Its all about seed source though and clearly I found an awesome source.

What makes me sad is that I can’t get a sycamore source that won’t die back. I got one from Quebec that it’s mother saw -35 yet mine died back to the snow line. I was just hoping as some areas where sycamore are native, have seen -40 lows over the years like some places in Iowa.

Do you have a sycamore source?

The winter of ‘13-‘14 did so much damage, including the trunk, I decided to remove it. Fall color really never developed in the short time I had it.

I don’t have a sycamore, but I know of a mature specimen that grows in town. It’s prety big and must be several decades old, which means it has been through some very cold winters. I don’t know if it is producing seeds, but I could do some arborial sleuthing.

That would be amazing. It’s the one tree I want in my yard that I haven’t been able to get going yet. I know they were trialing it at the Edmonton nursery last winter but they somehow kill Everything there.

They were trying London plane trees and I have no clue why. They died in a zone 5 winter that we had. They aren’t hardy at all.

How bad was that winter for you? And how cold do you think that sycamore has seen?

It was long, cold, windy, and snowy. The deer around here browse on a horticultural buffet, and they looked haggard coming out ot that winter. I lost several plants, but there were some surprises. I don’t even want to think about that winter.

I’m guessing the Eau Claire sycamore has seen -32F.

Below is my border stream in mid-spring with birch, redbud and katsuratree left to right. The katsuratree is growing in a narrow, upright fashion:

What kind of birch is that? It looks like a poplar... it’s trunk isn’t white or brown like I’m used to seeing...

Hybrid Himalayan birch I got from OIKOS. Supposedly isn't resistant to the bronze birch borer, but no problem yet. Very fast grower.....

Mail order in Canada is practically non existent!

London Plane in Toronto does well in some spots. If it is planted in a lawn without a sidewalk it does well. If planted in the boulevard it needs substantial water to do well. The city planted one in front of my house in a 8x8 area between the road, sidewalk and 2 driveways. The following winter we experienced brutal cold weather and an ice storm. From early spring I watered the hell out of it. Leafed out but about 8-10 inches of each branch tip were dead. I cut back the dead so the city wouldn't remove it. That was spring 2014. I keep watering (as well as an irrigation system), and it is thriving. They seem to need a lot of water to root well.

In regards to a Katsura having a smell, I have never experienced it although it was one of the nurseries marketing points.

ANyways, as per my original question, I have removed the oak and replaced it with a teeny tiny european beech. I had it in my front yard and transplanted it.

IME, you need the right combination of conditions for a katsura to release that tell-tale scent. And not all katsuras will offer it in the same degree - as an example, the weeping forms release no scent at all (or none that I have ever detected), named forms do to some degree and the species tree releases it most intensely. It is a naturally occuring chemical, maltol, that is released into the atmosphere as the leaves abscise (petioles separate from the stems) and drop from the tree. So best when there is some breeze or light wind to encourage abscission. And it will carry best if the air is not too cold - a sunny, warm fall afternoon is best :-) And the tree needs some maturity to it before the scent becomes very pronounced (might well be a factor of leaf volume - more leaves = stronger scent).

You can also get some light scent from the fallen leaves themselves although I find that to be very incidental compared to the actual shedding of the leaves/separation of the petiole that typically triggers the release of this chemical.

Katsuras are not the slightest bit drought tolerant and will respond to drought stress and dry summers by early leaf drop. And the early leaf drop will not produce fragrance. Same with any early frosts that would cause premature leaf drop or drying and shrivelling of the foliage before the leaves colored up and fell naturally.

This Katsura was detectable from over by the church across the pond, a couple of hundred metres away.

I went looking for it since the smell told me there must be one around somewhere.

That’s fantastic. I really hope my tree “learns” to colour up earlier. I’ve watched lots of other trees adapt through the years and change earlier when in places that have earlier frosts after a year or two of getting burnt off. That being said, these last two years have been extremely abnormal as far as killing frosts so early so it should get better.

Gardengal, how do you know so much about the Katsura? It’s fascinating to read. Do you have a background in horticulture?

GG my neighbour has a weeper and it does release the caramel scent in some years. But not this year for some reason,