By Barbarak
North Yorkshire,
United Kingdom 
Dahlias. I have lifted my dahlias early as I will be away from home for all of November. There are a couple of tuber clumps that have 5 or 6 stems but the clump of tubers is the size of a football. I have plenty of small tubers that have been grown from cuttings this year. Does one dispose of huge tubers?
23 Oct, 2017
Answers
You can divide the huge clump of tubers into individual dahlia plants as long as each division has at least one "eye". The "mother" tuber that was originally planted can be discarded and you keep the newer, more vibrant "babies" give them away or sell them.
Here are instructions on just how to do it. It's very easy with a very sharp knife.
How to Dig and Divide Dahlias
https://www.thespruce.com/how-to-dig-and-store-dahlias-1402256
24 Oct, 2017
If you want to, throw them away, otherwise, store over winter and split the tubers in spring,when you can see where the eyes are.
23 Oct, 2017