Are we talking the Driftless? If so, here’s probably how I’d start
Mayfly Dries:
Adams 14 - 20
BWOs 16-22
Sulphurs 10-20
Tricos 20-24
Hexagenia 6-8
The BWO’s will take care of the BWOs, the Sulphurs will handle everything from size 10 Light Cahills to size 20 Sulphurs. The Adams can probably take care of anything in between. If you’re up at dawn, Tricos will start happening around mid-July. On the other hand, if you’re willing to fish in the dark, the Hex’s will come off in mid-June or so.
Caddis Dries:
Tan and Olives: 14-20
Black: 16 - 20
Gray: 16
Midges:
Griffith Gnats size 18-22
Mayfly Nymphs:
GRHE (various shades) 10 -14
PTNs 16-22 (wouldn’t hurt to do some with pheasant tail dyed in olive and black)
Hex Nymph (they work during the day prior to the hatch at night)
Caddis nymphs:
Mercer’s Z-wing pupa:14-18
La Fontaine Emergent Sparkle Pupa (various colors) 14-18
La Fontaine Deep Sparkle Pupa (various colors) 14-18
Czech Nymphs 10-12 (Olive, tan)
Peeking (cased caddis): 10-14
Other “nymphs”:
Pink Squirrel - #10
San Juan Worms - Pink, Wine, Tan Brown (every farm kid knows to fish worms after a rain, you should too!)
Scuds in Tan, Olive, Pink, and Orange sizes 12-18
Wets:
Partridge and Olives: 14-20
Partridge and Yellows: 14-20
Starling & Herls: 16
Terrestrials! I catch more fish on terrestrials than on anything else. I like to start right after the MLB All-Star Game
Ants: 16-20, winged and unwinged
Beetles: size 14 (lots of people go smaller). I tie mine in foam
Crickets: Size 12 and 14 (2xl)
Hoppers: Size 10 (2xl)
I find crickets work better earlier in the terrestrial season while hoppers work better later.
To tell the truth, I’ve never used a streamer in the Driftless. On trips East and West definitely, but never in the Driftless. The streams are so narrow that it seems impossible.