Serendipity is defined as "the occurrence and development of events by chance in a happy or beneficial way". Not sure the following actually conforms to the definition, but I found it sorta neat.

In order to neutralize some acid, I mixed up a couple tablespoons of baking soda in about 12 ounces of water. I used a short piece of 3/4X3/4 red oak as a stirrer (it was handy). I laid it aside for a few hours and it dried to a pleasing dark (aged?) brown. 
Don't know if this was a reaction to the tannins, or what. Gonna try it on some maple, poplar and walnut. If it does the same with the poplar, might have a solution to the green streaks that relegates poplar to a secondary wood status,

Gene,

Here's a link to something similar-

http://www.wikihow.com/Age-Wood-with-Baking-Soda

Lew, 

Adding tannins, like tea, might help with woods with less tannin acids. Any thoughts?

This video has some information about several products to "age" wood

I believe ammonia fume will also age wood guys but I've never tried it.

Ammonia Fuming of white oak was a finish popularized during the A&C period by Stickley. Not all woods will react in the same way as the ammonia reacts to the tannins in the wood. White Oak works well but Red Oak will tend to get a greenish color. Here is a short video from Fine Woodworking about fuming an A&C style table. It is a pretty straight forward process.

http://www.finewoodworking.com/how-to/video/how-to-fume-furniture-with-ammonia.asp

I did a little experiment. The results were somewhat illuminating.

Dipped a stick each of walnut, maple and poplar in a solution of 1/2 cup of water and two tablespoons of baking soda. That darkened the poplar somewhat, the maple not at all and the walnut quite a bit.

Then, I made some tea. A one quart sized bag in 2 cups of boiling water. Let it steep for 1/2 hour. Washed a stick of each wood with the tea. Let it get pretty dry and then dipped it in the baking soda solution.
The maple took on a really golden honey color, quite nice. The light part of poplar got pretty dark and the green part turned brown. The difference between the light and dark became quite muted. Still discernible but not nearly as stark as before. The walnut got a shade darker than the piece just dipped in the baking soda solution.

With all but the poplar, I think the same effect could be had with stain. But, my experience with staining poplar leads me to think that a pre-treatment with the tea and baking soda would at least produce a more even color after staining.

As to white oak, Phyllis and I experimented with fuming using ammonium hydroxide to darken our white oak A&C style kitchen cabinets. While the effect was very nice, we decided that the process didn't lend it'self to a whole kitchen of cabinets. We opted to dye them and were successful in achieving nearly the same effect.   

Guys, don't forget about simply leaving your project out in the sun all day to deepen in color as well before you finish, it will turn many shade of dark in a day of sun.

Sun? What's that?

Left to right: Walnut, Poplar, Maple.
Untreated on the left of each treated sample.
Crappy camera. The poplar’s untreated piece didn’t show it’s contrast between the light and dark. But, there is quite a contrast.

well Gene sun is what we get alot of here in Texas,and i never thought of puttin my poject out in the sun,will have to try that an post pics of it for yall

Sun? What's that?

I'd like to know too.

Sun? What's that?

I'm not sure Gene,

After 10 days of below freezing temperatures we were rewarded with 1day of 32° and 3 days of 40's-50's.

It has rained all 4 days, and will be snowing this afternoon. We are forecast for another week of below freezing temperatures.

It must be Nocember, or Nanuary here.

We are heading for the high 80a here in CA!

We are heading for the high 80a here in CA!

Now that's not Nice.   

 

Rub it in, Rub it in.   

 

But You CA people couldn't handle what we're getting.  

47º here on the mesa but, headed for 70º by midweek. 

We are going to Tucson for Christmas. Supposed to be in the 80's. 

My old bones are too brittle for skiing anymore, but when I was stationed down there, we went skiing on Mt Lemmon Christmas morning and went swimming in the base pool that afternoon.