Oh my. Five years, huh? How big are these trees?

Personally with Norway/Silver Maples I say it would be cheaper and less trouble to mail order 3ft tall easily transplanted bare root trees in the spring.

They'll establish quicker than the larger transplants and these trees grow fast! Its also neat to see something you planted do well.

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On a side note I'd love to see pictures of the material around the roots. Something to show doubters in the industry.

Some industry burlap is advertised as biodegradable. Many many companies leave it on for ease in transplanting. For the love of nature I don't understand why they can't at least cut the sides off after the tree is in the hole.

is there any reason you are attached to the maples????

there are a plethora of columnar confers that would add so much more to your landscape ...

ken

Columnar Norway maples in Denver?!?!?!?!?!?!?!?!?!?!?!?!?!?!?

Nonetheless, bad choice notwithstanding, I am involved in a lawsuit over this very thing. For some reason, there are a lot of contractors around here that simply are incompetent boobs and this is, sadly, common enough to not be a surprise. Stapleton has literally hundreds of trees that suffered this same fate - incompetent boobs, dead trees in wire and burlap. Start over. But not with columnar Norway maples - a worse choice for this area would be hard to come by. Sorry.

And in this place, burlap does not break down quickly. Even planting out in peat pots is ill-advised.

Dan

I am definitely not in love with these maples, or any maples in Denver for that matter. I have learned much in 5 years and one lesson is never to let a contractor substitute different trees for your original (better researched) choices. This guy lobbied hard but I think it was because he could not find the tree I specified in the size requested. The root balls were wrapped in true burlap (not the plastic burlap) inside of a wire basket and then wrapped outside the basket with clear shipping plastic. I have seen this done on other occasions to hold the burlap tight and thus the root ball in place during trucking. Honestly, removing the plastic wrap is a 20 second job. Once in the ground, the burlap had mostly disintegrated inside the plastic wrap, but the tree roots were girdling inside the plastic, or growing over the top of it to get out. This particular contractor offered a two year warranty on trees and actually replaced two others that flat out died. But these were dying a slower death. I suppose I could claim shoddy worksmanship and see if a settlement could be reached.

Which columnar trees (excluding arborvitae and conifers) would be better choices? The location is the east side of my house and I do not want year round shade.

Lots of substitutions in Denver because not too many trees grown here. When I used to to Plan Review to the south of here, I had lots of substitution attempts and not a lot you can do about it except reject their (usu uninformed) choice or live with it or wait 'til next year. There are a couple columnar English oaks you see around here that are OK, but I don't care for them. Downtown there are plenty and the light rail station at Alameda has maybe ~1 dz. They hang onto their lvs for several months in winter.

Dan

Well, my wife wants the trees. How about this idea - dig up the entire tree and lift it out of the hole (this won't be hard since the roots are girdled, and then remove the plastic and replant it. Any chance of survival if I do it before the tree leafs out this spring?

Not a good plan and not likely worth the effort. If the roots are girdled/circling similar to one removed, you are only delaying the inevitable. And removal costs down the road could easily be more than they are now. Also the potential liability of a failing tree falling. Better to make a clean start - remove the trees and replant correctly with a more appropriate choice.

If you want a columnar tree form, consider hornbeam, Carpinus. Both European and American hornbeams come in columnar/fastigiate models and they are tough, tolerant and pretty much pest-free trees.

I don't know about how Norway maples grow in Denver, or the nature of the particular cultivar you are growing, but Acer platanoides is one of the most invasive trees in the Northeastern US. They are a scourge here and have been prohibited from import or sale in my state. I spent a lot of money removing 4 (out of 5) large Norways and wish I could snap my fingers and have the last one removed too, but it is huge and would probably cost at least $1K.

These trees are hardly worth heroic efforts. The fact your trees were planted in plastic has probably already ruined the integrity of the root structure. From what I understand, this species has some issues with girdling itself to death anyway.

Why would your wife want a poorly-adapted and sickly tree unlikely to flourish or in this case, recover?? She's gonna have to deal with the reality of this situation (he says from far away).

Carpinus get marginal leaf scorch here on the Front Range and some sooty mold from aphids, but if you can put up with that and ensure it gets plenty of water, it will work here too, and it is on Denver's private tree list.

Dan