Thanks TXEB!

Hadn't heard of "forbidden rice" before, so went and looked. I quickly discovered that it's whole grain black rice. I believe that means it is, effectively, a seed. If you put that directly in your soil I suspect you will get rice sprouts. So chemistry aside, it's probably NOT a good thing to add directly to soil.

Forbidden Rice is sold as a food but rice is a seed and as a seed has all of the nutrients the plant needs to grow until it can start to photosynthesize and manufacture the nutrients that plant will need to grow to produce more seeds.
You could add that rice to your soil and if the conditions are right that rice may germinate and grow. I have not seen rice on the list of green manure crops but it might work for that.

I wonder if it would draw pests? Certainly the birds would eat it off the surface, but that may not be a big deal.

Have you considered freezing the excess, or donating to a food bank? Seems a shame to waste edible food.

I know that Basmati rice is best if its aged several years, they do this in India, Iran, etc. I wonder if Forbidden Rice could be aged as well.

IOW, if you sell food or medicine in the US, by law you have to put an expiration date on the container. Maybe Forbidden rice can be kept for 4-5 years and it would taste even better......

I was also wondering about the rice going 'bad'. Certainly white rice can be stored for years. Does this rice have an expiry date on it? Brown rice in my cupboard has a year's date on it but I will certainly ignore that if I still have it then. Or, as toxcrusadr said, you could always freeze it.

I too like forbidden rice. I do know that rice absorbs a lot of moisture so just keep that in mind. I do believe Forbidden rice is the only rice with its hull in tact. I have been researching this very thing and I'm torn about using it. On one hand i think the whole rice will help aeration in the soil and deposit nutrients once it breaks down. And will also help clay soil not stay as wet from heavy rain. On the other hand you would probably need to consider how much moisture rice absorbs when watering the garden and adjust it to compensate. I have mostly found information about rice hulls not much out there about the grains themselves. You can always do a test area and see how it goes.

Also it takes an obscene amount of water to grow rice. So even if it sprouts it will not survive unless you are intentionally trying to water the area for it to live to maturity. And you can compost or otherwise use anything that does grow. Or till it under in the fall.

And if stored well and away from moisture any rice will last years past the best by or expiration date

You were talking about having a grinder or mill. I know rice water is great for plants look into that as well. You can create lactic bacteria from rice water.

If I had an overabundance of rice or any grain and also had a grinder, I'd consider making flour or meal to use in other recipes. Plenty of things can be made from rice flour.