Coriander by the gallon?

I'm working on cloning a Belgian Wit from a WI brewery and ran across something odd in the info I found. The brewer said he "adds about five gallons of coriander for each 15-barrel batch". I've never heard of coriander by the gallon. Is he making a coriander tea? Anybody hear of this before? A little googling didn't lead me anywhere.
The other odd thing is he said the grist is about 1/3 wheat which seems pretty low for this style but whatever.

No, he is literally adding a gallon of ground coriander to each 15 bbl batch. 15 bbl = about 465 US Gallons. If you have ever worked in a restaurant, a lot of spices come in huge gallon containers. He is probably buying something like that through a restaurant supplier. If I were you, I'd look at a few homebrew recipes and figure out how much people typically use instead of trying to scale that down. You are probably looking in the 1-2 oz range.

I've never worked in the food industry but buying in sizes that big makes sense for them. Thanks for the tip.

I use 1oz in a 5 gallon batch. That's BM's Black Pepper wit recipe.