What to Wear to a Wedding on a Ranch? – Help Laurie!

Alright, I'm desperate for help, and starting to get a little nervous.

I'm going to a wedding in two weeks and I have NO idea what I'm supposed to wear.

The wedding, for Duzzy's stepbrother, is at a ranch...in Las Vegas.

I have zero clue what one wears to a wedding at a ranch, but I've been told it's not a casual wedding...so no cowboy boots. Or can I do boots?

I've found a couple of dresses that I like enough, but are they wedding-y? Are they good for this time of year? On a ranch?

Gah. Please, tell me what you think of these...or send me ideas! I need your help!

(I would normally just ask the couple...but I've only met the groom once...and Duzzy doesn't really talk him much.)

This one is cute, but I feel it might be an awkward length...it looks like it hits just below the knee, which means it would look frumptastic.

Nice enough...just seems kind of plain. (If you're wondering what's up with the teal, I just like the color...)

This one is available in LOTS of different colors...I'm just not sure if it's dowdy looking, and/or if would highlight my lovehandles -- the bane of my food-loving existence.

Or maybe I SHOULD just do the sundress/denim jacket/cowboy boot combo?

Help!

What would you wear to a ranch wedding? Leave all of your suggestions in the comment section below!