viability of lager yeast from September?

[hexmonkey]

I just realized that the Wyeast 2206 I was planning to use tomorrow for a Marzen has a MFG date of 9/22/09. MrMalty.com's yeast calculator says this packet is only 10% viable, so I'll need something like 10 packs of yeast(!).

This is my first lager, and I'm aware that they require more yeast, so I have my stirplate ready...

How accurate is this estimate if the yeast has been in the fridge and I'm making a starter anyway?

 

[avidhomebrewer]

I would be very suspect of this yeast. Wyeast 'claims' that it is good for about 6 months, but I have used yeast older than that already with no problems. However, I haven't used it the next day!

I would imagine that you smacked it and it took off after some time? If so, go ahead and make a starter with some yeast nutrients to 'bring it back to life' and see where it goes from there. Make sure your yeast is ready to go before making the batch because with a lager, it will be in there for the long haul.