Best time to take crabapple cuttings?

[zxcvbob]

Was gonna ping Giga, but who knows who else might be knowledgeable about such things...
I want to take cuttings from a crabapple tree at the county wastewater treatment plant.  I don't know the variety (I think it's Dalgo) but it's the only crabapple tree I've found in the whole city that has fruit good for making jelly, or for eating fresh if you like sour apples.   I'd like to propagate it.  I've looked online and I'm finding conflicting information.  I would air-layer it in early summer if it were on my property, but of course it's not.

I think maybe softwood cuttings in late spring right after it blooms?  Make a few vertical slits in the base of the cuttings with a razor blade and dip in rooting hormone powder (Rootone), then plant in a 50/50 mix of sand and potting soil.  Does this sound about right?

[RoadKingLarry]

Go for it, worst that could happen is nothing grows. For a crabapple I would also think planting from seed would do fine since it likely isn't a hybrid.

[Regolith]

If crabapples work like regular apples, you'd need to do a graft onto some rootstock to make sure you get the same type of fruit. Planting from seed could get you anything, since apples don't breed true, and I don't know that a cutting would root.

ETA: Doing some more research, it looks like grafting is preferred because it has a much higher success rate. I guess if you took enough cuttings, you might get one or two to grow.

ETAII: More research: https://www.hunker.com/12339553/how-to-plant-apple-tree-cuttings

Says to take them in late spring.

[GigaBuist]

Not something I do but online instructions seem pretty on target to me.  Here's the first thing that popped up:  http://homeguides.sfgate.com/grow-apple-tree-cutting-63550.html ... nothing seems suspect to me there.

With regards to grafting that's done to control the size of the tree.  Rootstock trees are bred to control size and taste is bred elsewhere.  Honestly most of the rootstock is bred in Russia and the University of Minnesota breeds most of our new apples then puts them under patent.  The Badgers are crossing trees willy-nilly to get something with a new taste and when they hit gold they patent and release it.  Problem is most apple trees want to be 30-40' tall which doesn't fly for a commercial orchard or even a home owner, so they graft them on the Russian rootstocks to keep them small.  True dwarf sizes only get about 7' tall but they're weak as heck and need support so you only see them at actual orchards. Semi-dwarfs get 12-15' tall but can stand on their own so that's what you're typically buying as a consumer.  Snap a whip off a 7' tall SweeTango at an orchard and root it and you'll probably get a giant beast tree.