Do they make big water-softeners for irrigation? I know there are stones that can buffer excess acid..are there stones that can do the same for excess alkalinity?

Can you collect rain water from your roof to use in the area around the tree for at least part of the year since it will have a lower pH and no dissolved solids? Also, IME long, slow deep watering is better than short watering times more frequently. Longer times will allow water to soak in deeper to encourage deeper rooting.

Location, location. If you're in an arid climate where the only substantial precipitation is your irrigation, than you have a potential problem. If you're in a more mesic environment and irrigating only to compensate for periodic dry spells, than you're probably ok.

"Do they make big water-softener for irrigation? I know there are stones that can buffer excess acid..are there stones that can do the same for excess alkalinity?"

Residential water softeners substitute calcium and magnesium ions for sodium ions. That ion exchange makes the sodium rich water worse for irrigation than water w/o sodium (just calcium & magnesium TDS)

Alkali soil

I do have a small rev. osmo. unit, but produces only enough for the potted plants.

I'm in Inland Orange County, CA.

How often is leaching (slow deep watering) needed, in order to keep the salt down? Perhaps a soaker hose (under tree) would work after the lighter lawn watering. I want to avoid overwatering the lawn, in order to leach under trees, and thus causing run-off (waste).

Barring another shower or two, the rainy season is over.

in essence.. ed is right .. it is a water softening type system ... but not quite what we would all associate with what happens in the house ...

i have visited many greenhouses ... where ... if you look or ask ... they inject fertilizer into the water .....

there would be no reason.. if they wanted.. they couldnt adapt the system to balance pH ....

im not interested in researching this much further.. but the link should lead you down the road ... the 4th link looks interesting ... btw .... a very short perusal of that link .. have you have a professional soil test done ... to truly define your problem????

ken

https://www.bing.com/search?q=irrigation+injector+for+pH&pc=MOZI&form=MOZTSB

A winter of good rainfall such as we just had in Southern California does the trick. If only we got that rainfall every winter! Collecting rain water and distributing it for extra soil cleansing may help.

What trees do you have that you consider vulnerable to alkaline conditions and tds?

Acer Truncatum. It does better than most maples. Since it doesn't start to burn until late summer, maybe I should leach in June or July. I may try Redpoint Maple, also, it is advertized as being quite tolerant of alkaline soils.

Supposedly pine needle mulch, pine bark mulch, catalpa leaves, and sphagnum moss acidify the soil. It's been established they aren't enough to significantly change the pH of soil that is alkaline...but if the alkalinity is coming in gradually from the water maybe they would help.

Are you looking for more trees? Bur Oak (Quercus macrocarpa) is tolerant of alkaline soil and salt. Yellowood (Cladrastis kentuckea) is tolerant of alkaline soil and gorgeous.

Yellowwood requires winter chill to bloom; ain't gonna get it there. If you are ever over by Mono Lake they use maples as street trees right outside the visitor center in town. I don't remember which maples but they have really attractive white-ish trunks and the overall tree looked really nice. Check them out if you're nearby; they would do well in your climate and presumably can handle the soil pH. (The pH of Mono Lake is about 10, but this is a few miles away.)

Wow, Sara that really surprises me. Are you sure they aren't not London Plane Tree? I will try to google street-level map of the area on Google.

Ok, I found them in Lee Vining. Just my luck though, they are dormant in the streetlevel pics.

I found an article that says the street trees that were installed were red maples.

They sure don't look like any red maple I've ever seen! And yes, they were in Lee Vining. I was with a group of plant nerds and none of us knew what they were, so I seriously doubt Acer rubrum, unless they were a cultivar that I've never seen before (which is entirely possible.) We were all surprised that any maple looked so good; it was August and about 100 degrees and bone dry air.

I would be willing to bet it is Redpointe. The shape of these trees appeared pyramidal, as Redpointe is. It is somewhat new, intro'd by Schmidtz. They found it growing wild at the nursery, beside an area growing Freeman's and other Red varieties: http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=/netahtml/PTO/srchnum.htm&r=1&f=G&l=50&s1=PP16769.PN.&OS=PN/PP16769&RS=PN/PP16769

Could certainly be. The reason that this tree is so distinct in my mind is that the group of us (five plant nerds) all remarked on how great these trees looked in such an inhospitable climate.

After Easter, I'll call the town landscaping division. It's probably one guy or two. They'll at least know where they got them from. I wouldn't doubt it, if they purchased them from a place in Visalia, CA. Can't remember the name of the nursery. It's even more surprising that they are surrounded by cement sidewalks. That concrete gets quite hot, too. Also, consider the cement leaching all that lime down into the rootzone. I wonder if they use salts on their sidewalks after winter snowfalls.

Yeah all of those reasons are why we were surprised to see them there, looking so good! We asked inside the visitor's center but of course they didn't know what they are. If you find out, update this; I'm curious.

I will.

You can acidify the soil with Sulphur pellets. It's what I use on my Proteas that want acidic conditions.

Yes, my other concern is the amount of salts in the water I irrigate with. Hoping I can flush them below the roots.