Starting with one yeast and finishing with champange yeast...

currently in the process of making a Belgian tripel - it has a fairly high original gravity (1.076) and unfortunately I'm not at the stage to make yeast starters. I have one vile of White Labs Belgian Ale yeast but I'm not sure this one vile will get a high enough attenuation. I think I've read somewhere that in order to get around this I can pitch some more yeast and the yeast you use at the end of fermentation really doesn't effect the flavor characteristics of the beer- I have champagne yeast and was wondering if pitching it after the Belgian yeast has finished would be a good idea? The FG for this style is quite low and I would really like to be able to hit it in order to get a nice dry finish

First, your Belgian Ale yeast should finish; it might take a coon's age, but it may just do the trick.

Second, why not just pitch the appropriate amount of the appropriate yeast? If you get another vial of WL Belgian Ale yeast and pitch two, you ought to be all right. Two vials (and patience) will get you closer to your desired result than pitching in a champagne yeast packet.

Cheers,

Bob

why can't you make a starter ? how long has it been fermenting ? whats the gravity at now ?

The low FG of a Tripel is partially due to the Candi Sugar. I'd hold off on the champagne yeast until the ferment stalls, if it does.