Scarified in 95% Sulfuric Acid for ~45 minutes then stratified for 30-45 days. Worked like a charm...they started germinating in the fridge. Not sure what the rate was but I had more germinate than I could plant....it was probably 75-85%.

I soaked in water a few days and then filed through the seedcoat with a nail file (BTW, this technique works much better on Kentucky coffeetree seeds - they are bigger, easier to file, and I got better germination rate). Got 20-30% germination maybe. Gave up the experiment though - the parent trees succumbed to our zone 4 cold, and they weren't high on my list.

Where can you obtain sulfuric acid? Is there a specific concentration (Mol I think?) that works?

I get nervous about using it - that I'd burn either myself, or, more likely, the seed embryo.

This post was edited by hairmetal4ever on Mon, Aug 11, 14 at 10:42

Small numbers...I'd just nick the seedcoat with a nail file or a little snip with nailclippers - just enough to let water get in to the interior.
I guess if one is doing large numbers, the sulfuric acid deal might be worth fooling with, but I'm not gonna mess with it.

@hairmetal4ever
http://www.sigmaaldrich.com/catalog/product/sial/258105?lang=en&region=US

You are right to be nervous. I'm lucky, I had a lab I could use with all the glassware, safety gear, and procedures already available.

After 30-40 minutes, the seeds started to bleed color (like a teabag) into the acid. I diluted the acid and then rinsed the seeds at ~45min.

You could try a lower acid concentration and leave the seeds in until you saw the color bleed starting. HCl (Muriatic Acid) for a pool or battery acid (Sulfuric Acid) can be bought fairly easily. You may need 2-3 hours or more of soak time b/c they are at much lower concentration than the 95% Sulfuric.

I've grown a few of these by seed. I started by taking a file from my toolbox and filed away the seed coat. Don't be shy about this. It'll go from dark brown to light brown to whitish. You're through when you hit the white. Then I put them in a glass of water for a day or two. You should see the seed swell up from absorbing water. Then plant. I've had seeds several years old germinate.

Bumping this since I ordered some seed from Schumacher's.

Is the seed shaped in a way that it's obvious where the embryo is? If I nick or file it I don't want to cause damage to the embryo or seed leaves?

Which brings the next question - do the cotyledons turn above ground or are they hypogeal?

If you're going that route, IMO, plant seeds where you finally want them. After a couple yrs, they're difficult to transplant & don't handle it well. The shellbark hickory I transplanted hardly noticed, but transplanted KCT suffered badly for yrs & the stem finally died, but has resprouted from the roots.

I have the seeds. The seeds are almost identical in appearance to Cercis canadensis seeds.

So it sounds like the 60 days stratification recommended by Schumacher is overkill?

I'm shooting for a sprout date of April 1. In root pruning containers outdoors-by April 1 to threat of hard freezes is usually past (below the mid 20s) and the 2 to 5 nights we might get below freezing after that, it's easy enough to protect them, bring them inside etc.

The 60 days stratification as recommended by Schumacher is indeed overkill.

As said above, use a nail file and carefully file away a small part of the seed coat. This is a @#$%^ job, especially if you have large fingers. Alternatively, you can put the seeds between two sheets of sandpaper and rub these against one another.

Then soak the seeds for some time. Seeds should swell. If not then file anew.

Now you can sow the seeds. They will germinate in 1 to 3 weeks time.

Hair,
Blackgum was the first tree I started from seed. Out of 5-6 plants that I began with, I had one at 14", another at 24", and the rest were 18"-20" in height at the end of the growing season. So be prepared to pot up over the course of the growing season. I started with small peat pots for the seed, that I then transferred to a larger pots without removing the peat pot. Used Osmocoyte Plus monthly, and watered daily, full sun.

Arktrees

Hair,
Hit the wrong thread by mistake. I was answering your size expectation thread. Sorry for the confusion.

Arktrees

No problem, Ark. Thanks for the help regardless.

As far as the Yellowwood, I did a small "test run" on three seeds. Filed a spot with fine sandpaper until I saw white. Did three seeds and all of the swelled when soaked in warm (100F) water than I allowed to cool overnight.

I then put them in moist paper towels. One did show a radicle after three days with no stratification.

I also figured out the best spot to file them. The seed look like tiny little beans, and the scar on the side, which is where was presumably attached to the pod, is slightly off center. The root emerges from the end closer to that scar. So to avoid potential damage to the embryo if using the filing method, I will file the opposite end.