I've read that arm and hammer's Super Washing Soda and soda ash are the same thing. But I've been looking around the internet and it seems soda ash might be more harmful than A&H's Super Washing Soda. Is this the case? I've been using washing soda for making homemade detergent and heard that soda ash at the farmer's co-op is the same thing.
Hey, thanks. I went ahead and used it based on that suspicion.
I found this to be a bit helpful http://www.wisegeek.com/what-is-soda-ash.htm
Been doing some reading. There is a naturally occurring form of soda ash derived from plants. Most soda ash is made by the Solvay process which involves mixing chemicals (such as ammonia) together.
http://www.robinparis.co.uk/sustainable/soda-ash.htm (there is a section here about natural soda ash)
I've been looking and have yet to find a source for plant based soda ash in the US.