p. 44 MitS

It states that using a number of alchemical radicals equal to the force of the focus reduces the TN for enchanting by a modifier listed on the enchanting table. However, I can't seem to find the modifier listed on the table or in the errata.

Can someone help me out here?

The part "Alchemical Radicals" at the bottom of the table on that page, just before orichalcum. It takes (force) units of a single material to count as one material.

Ah the second part is what I was misunderstanding.

So, if I had a force 3 focus and I wanted to -4 modfier for three materials, I'd have to have 3 herbal, 3 mineral, and 3 metal radicals?

That would be a valid combination to get the effect.

Actually, after re-reading it again, you'd need, 1 herbal, 1 mineral, and 1 metal radical (minimum) to get the modifier.