Not seeing any pics. Anyway, not much you can do except remove the dead portions and wait. If there is not much viable growth left I would not be going in trying to shape it- it needs every leaf it has purely to sustain itself. After a year or two of looking at it you can decide whether or not it is worth keeping. I would certainly give it that amount of time, though, seeing as you have a sentimental attachment to it.

This is the recipe that is most often recommended for long term container plantings, including any type of tree: 1 part uncomposted screened pine or fir bark (1/8-1/4") 1 part screened Turface 1 part crushed Gran-I-Grit (grower size) or #2 cherrystone 1 Tbsp gypsum per gallon of soil CRF (if desired) This is what is commonly referred to as "gritty" mix - it is extremely durable (holds up long term) and provides both fast drainage and excellent aeration. Depending on where you are located and the suppliers that service that area, it is possible to purchase a suitable bagged potting mix that very closely replicates the texture and durability of the above recipe - Kellogg Garden products makes such a mix (sold under a couple of brand names) that is intended specifically for trees, conifers and most broadleaf evergreens. But be aware that most prepared, bagged potting soils tend to be comprised of too fine particles and are too moisture retentive and therefore too liable to compaction or collapse. Growing a JM in a container is a bit more complicated than growing one in the ground. More attention is necessary with regards to watering and fertilizing, there will be a need to be aware of and make provisions for winter protection in cold winter climates (anywhere zone 6 or below) and there will be a need for routine periodic root pruning and repotting. And while I agree there is less of a need to focus on adjusting pH for JM's with a container soil mix, in areas that tend towards alkaline water sources - much of the southwest - I would recommend you neutralize or slightly acidify the irrigation water with household vinegar (1-2Tbs per gallon). There is a search function at the bottom of each GW forum page that can facilitate looking for additional info on both growing in containers and more specifically, growing JM's or other trees in containers. Just type in the topic and the results will pop up. I'd suggest you search this forum for other discussions of growing JM's in a container - there have been many over the years - and the Container Gardening forum for a broader approach, such as growing trees in containers, how to fertilize and with what and general container growing topics. And I'd suggest you start with the following attached link. It is probably the most widely read and responded to thread in the history of GW, written by a recognized authority on container gardening and containing a vast wealth of information. Here is a link that might be useful: Container soils - everything you need to know

You don't say where you live..It looks to me like a winter bark cracking if you are from a colder area or the spring freeze..but that is a bit unusual for an older tree ..I have had younger hard maples and fruit trees do this..it usually heals over time ..but it could be vermin or something else I would have your local extension service or a licenced arbourist look at it ..without on the spot inspection we might do more harm than good with arm chair diagnosis..I think it could be serious and my instinct it is a bark defoliating thing that could be a symptom of something much more dangerous..I personally don't agree with Matt on this or your statement of storm damage ..i have seen this before and it looks like a bark related thing to me NOT storm stress...but as i said your best bet is to get a pro analysis.David

I'm not sure I agree with David entirely :-) CG's are naturally weepers but the ultimate height any individual tree will attain will be based on the location of the graft and how it has been trained. If you want the tree to top out at around 4', give or take a bit, there is no problem in removing the supporting stake now - it will not break (unless there is a possibility of a very heavy snowload in winter), so no worries there. A 4' CQ is not a juvenile graft - this tree has been grown on for a number of years to attain that height. It often takes considerable time for a JM trunk to gain much girth and to leave it staked for that long a period is IMO a mistake. I'd also caution about heeding any advice regarding pruning to reduce height - this is NOT a practice you want to follow with a JM. Pruning should be limited to enhancing the natural form and branch structure or perhaps shortening any long, ground sweeping branches and of course removing any dead wood or conflicting branches but it should not be done to reduce height, particularly on a form like CQ. Some of the most handsome specimen CQ maples at our nursery are no more than 3-4' tall but with a wide, cascading canopy 6-8' across. Rather than a "Cousin It" look, these have a broad, umbrella-like appearance - very graceful but with a need for sufficient space to show them off properly.