Should I use fresh or can dry sumac powder be used?

I've used sumac for years in cooking, only found the red powder version for cooking and never saw fresh on sale.
Apparently, sometimes the berries are sold for food use.
But be careful of foraged sumac, as there is a poisonous variety.
See article for more info.
https://www.masterclass.com/articles/what-is-sumac-learn-how-to-use-sumac-with-tips-and-8-sumac-recipes

I think it’s the dried powder. A tablespoon is a lot of sour! I’d add it to taste.