Couple possible issues
1. I was playing around with my Druid and I selected this trait and was going to use Produce Flame as the spell but Produce Flame is not on the list.
2. The wording of the trait says pick a spell. It doesn't say pick a spell you can cast or pick a spell from your spell list. Unless their is errata or something it seems you could pick ANY spell even if you can't currently cast it.
1. I was playing around with my Druid and I selected this trait and was going to use Produce Flame as the spell but Produce Flame is not on the list.
2. The wording of the trait says pick a spell. It doesn't say pick a spell you can cast or pick a spell from your spell list. Unless their is errata or something it seems you could pick ANY spell even if you can't currently cast it.