thanks for the link, and advice.
I was planning to replace with acidic soil. Is there any type of acidic soil that works better with red maples?
The water is an issue. Collecting rain water is one thing I am planning to do, as well as treating the water from the pipes, if possible.
I have many maples, japanese and sugar maple, but only the red maple seems problematic.
Thanks again.

Pine needles and composted pine bark are some of the best acid adjusters to soil.

It usually takes time to build or reduce the Ph of soil. Consider also that amended Ph in soil, if left alone, quickly reverts to the original Ph.

Thanks for the suggestion. I'll check into the pine needles option. I already use pine for the mulch. So you are saying I should periodically work pine needles and bark into the soil?

it depends on how much ph adjustment you need. If it is a moderate amount then virgin planting soil mixed with composted pine bark would be a good idea and later just a mulch of fine pine needles will most likely work for you.

If your soil needs a large amount of ph adjustment, then I would mix composted pinebark into the virgin soil in an area at least 6 times the diameter of the tree's root ball and at about 2 feet deep. Mix enough in with the virgin soil to make a 50/50 mix. Then continue using pine needles for mulch until you get enough red maple leaf drop to compost and use them for mulch.

I have also heard that lots of people in Fort Worth Texas go the the Fort Worth zoo and get manure. If such manure is given the proper time and treatment to be composted enough not to burn the tree roots, mixing it with the soil might also be enough to make your red maple happy.

One thing that you need to be careful of is to be certain that no horses will have access to your red maple tree's leaves after they fall from the tree. Horses like to eat red maple tree leaves, but it makes them very sick. If a horse eats too many of the leaves the horse could even die. I only mention this because not many people realize this fact. I even know of a local landscaper who planted two 10 feet tall October glory maples for a friend of mine who lives in a new housing neigborhood and who's yard borders a horse stable. As if that was not bad enough He told her it would be fine if he planted one of those trees less than 4 feet away from her concrete driveway. Now she is out the money she paid for the trees and the labor cost. She also is finding it very hard to choose to replace the trees with others that will be safe for the horses and that will not over time do root damage to her driveway.

thanks for the info. I'll definitely look into the pine needles option.
No horses where the trees are, only cats.

Supplement micronutrients instead of incorporating acidic amendments. Digging in coarse materials like needles or peat can also create excessive drainage, this could be quite a bother with a thirsty red maple. Any method involving planting into the existing soil, instead of on it (in a layer of different soil), will be subject to the influence of the existing soil. After the amendments decompose or the micronutrient supplementation is discontined the present conditions will resume.

So do you advocate first dumping acidic soil on top of the existing soil, creating a first layer of more acidic soil, and later supplementing with micronutrients as the soil PH starts to go up?

What type of micronutrients are you thinking about for this kind of tree? (Any specific brands that you recommend?)

Thanks a lot for the info.

We had lovely canopied Tulip Trees as sidewalk trees in our San Jose, CA. area neighborhood but they have been removed due scale infestation. The town allowed our street to vote on what replacement trees we wanted the town to buy ( from an approved list). It came down to a choice between the London Plane or the Red Sunset maple and the majority voted for the Red Sunset maple. a) Was it a good choice over the London Plane which evidently can get mangy looking with anthracnose or mildew and b) what suggestions do you have for us tree-naive homeowners to get the Red Sunset maples off to a good start and have them thrive long term?

The town expects us to plant and care for the maples - the town will purchase 15 gallon saplings for us and will provide stakes. Our soil is generally clay-like, our street gets full sun, our temps are pretty mild year round though it gets pretty warm for approx a month ( July) hitting high 80's/low 90's; no rain at all May-October either. Otherwise pretty balmy 70's-80's May through the end of October. We get approx. 20 inches of rain total January-April.

I've read that the Red Sunset maple is fairly adaptable, but is it this way from the start as a sapling or does it get adaptable and low maintenance after it has established itself? What about the Tulip tree roots - do we need to remove every last root tip before we plant the Red Maple in the old hole? Sorry for all these questions, but any suggestions would be very welcome.

Hopefully dumping suitable soil on top would enable you to get around the incompatibility of the tree with the site conditions, although eventually it would root into the native soil unless you provided a HUGE mound of more friendly soil. It's going to be pretty hard to completely defeat the fact that you are trying to establish a large plant in an apparently hostile location. With comparatively small items like azaleas or blueberries it is more feasible to provide a special bed, but 'Franksred' is a full-sized tree.

San Jose should be planting something more tidy than hybrid plane, a brontosaurean tree, adept at getting into utilites and lifting sidewalks, as well as emanating quantities of irritating hairs. Then there is the disease issue...Yes: it is silly that they are requiring you to plant one of two trees that they have chosen, yet neither of which is a better informed selection than you might easily come up with yourself. When specifying a red maple - a not very Californian item at all - they might at least come up with one known specifically for performing well in the South, such as 'PNI 0268' (marketed under the registered trademark October Glory).

Plant it in existing soil. Mulch and water in well, keep liberally watered (one of the common names of Acer rubrum is swamp maple).

Can you - or anyone else - recommend the micronutrients that would help a Red Maple over the years cope with a less acidic soil than it might ideally require? (Any brands?)

Same treatments as for rhododendrons or blueberries would probably be appropriate. But suspect soil should always be sampled and sent to a soils lab for analysis before products are purchased and applied.

Wow.

I just stuck my Red Sunset, October Glory, Autumn Glory, Autumn Flame, Brandywine, Somerset, and a bunch of other reds into the ground. Talk about blind luck, as they're doing beautifully.

Now, I have to worry about my new, growing Japanese Maple collection....

Christine

Thanks, Ron B, for all the info.