Obvious eye- looks like an unsitely pimple dead center, pale and raised bump.

45 degrees up to the right of it, see another raised lighter swelling with brown dots below. Another possible eye.

Same line 45 degrees further to edge of tuber, see another pink swelling. Another bump that may be an eye come Spring.

Straight up from the pale center eye, at the apex of tuber surrounded in crusty brown, is a depressed pink bump highlighted in two white flash dots; another potential eye.

There may be others here, but those are my best guesses on this tuber. Incidentally, this is Caproz Razbr'y Twinkle a very dark pink flower and I swear the tubers are pink toned too! Have never seen such a color on a tuber.

Here's another variety still on the clump: 4-5 eyes seen as slightly raised yellow swellings and a more prominent darker swelling dead center. The neck below it is what I will include when cutting these off the clump. The tuber neck to the right has no eyes connected to it; it goes to waste. The blurry tuber to the left has a small, pale swelling. See it? That would be a candidate for harvesting. Directly above the group of eyes pale greenish is the big stalk of the dahlia plant. To the far upper right marked in blue is another obvious eye, nearly sprouting, that will become another tuber.

Marked for you:

Here'e another obvious one, and possibly another eye to the upper right of the blue mark. There must be a reason I chose to mark this one, instead of the more prominent noogie to the right.

Here's the one next to the base of the stalk, as seen above. It isn't the most desirable tuber, skinny neck and all, but I'm going for it. The little fleshy broken tuber underneath it will be cut out later to get it out of my way.
I could have placed my blades/knife/cutting tool a bit further behind the obvious eyes, but I think this will work out. You don't want too flimsy tuber material supporting the eyes- breakage potential and all. I try to leave at least 1/3- 1/2 inch give or take.

Cutting the other side of that tuber, right thru the broken necked tuber, stabbing into stem material at least 1/2 inch deep. The final cuts will be underneath after I get the broken neck mess out of the way. And on top to sever anything the two side cuts missed.

The rugged looking evacuee, (but from photo 4.) A little sharp edged trimming and it will be ready to bleach, dry, sulphur, wrap and/or store.

This is the other side taken from by the brown mess on the clump. Cut off all brown or rust colored icky stuff from tubers. I soaked this in bleach water a good half hour after trimming it down to nice white tissue.

Final result: tidied up, labelled and ready to go.

One clump was Jennifer's Wedding, a deep purple flower: pink tinged tubers. The other was Jomanda a nice orange flower: also pink tubers.

Could it be fertilizer or something in the soil? The other clumps are all the more normal parsnip color- yellowy/tan. All dahlias were given equal treatment during the growing season, as far as I recall. Has anyone seen this before?

Also: any of you who suffer rodent damage: Are these holes visible in the tuber flesh looking like the work of an underground varmint? I've not had this problem before, but have noticed mole hills lately in the area. I have to tutor the moles to eat worms, not tubers!

Bites?

Nice pictures.

Plantylady I ought to put up my own toll booths shaped like mouse traps. Thanks for that info. A couple clumps were really gnawed on much worse than in the photo. Luckily, ones I have duplicates or quadruplicates of.

Thank you Poochella

Sue

Not all tubers will have eyes, you have to ID which tubers have obvious eyes, those that look promising, and duds and save them accordingly. If in doubt and you have room- save them all, but not all will have eyes.

Skinny ones will tend to rot or shrivel hopelessly in storage, but some might it. Skinny necked ones are prone to breakage, but might make it if handled with care.
Fat ones are slow to start up in the spring and can be trimmed off to inspire them to grow.

Here's a shot of where I cut a tuber out of the clump last year. You can see how the cuts were excavated about 3/4" cut at each angle to leave ample collar to support the area with eyes. Once you get a tuber off the clump you can trim up any excess junk and move on to the next one.

Sharp, thin blades are very useful as I find there is a lot of stabbing to get in where you need to cut.

Heidi41, some of the tubers are very tightknit and nearly impossible to divide but I've seldom run into any that can't be cut with some sharp object and a little muscle. Be careful! Make sure your blades are well-sharpened. Shorter blades are easier for me to control than long ones. You might want to support the clump on a wadded up towel as a cushion for all the muscle it sounds like you'll need. I've used a screwdriver and hammer to make some intial breaks too. Could help save a neck from breaking.

Blackiris, different dahlias produce different shapes/sizes and numbers of tubers. I know nothing about dahliettas. Below is a clump whose stem was broken off below ground level.(It's a tiny clump as it never got a good chance to grow before getting mowed down by a falling dahlia.) You've already rinsed the tubers- that's step one. Then trim off the rat tail roots and little roots, any broken necks or rotted tubers, most of any stems to get them out of your way. This little clump only had one good tuber off of it, (on the right) the two facing the viewer parallel to the tag are too skinny to save, even though they had obvious shoots/eyes.

Here's an older clump given to me, still with dried soil on, but several years without dividing made it quite a task to separate all the stalks/tuber clusters etc. You just have to study it and start and know that some tubers will be broken in the process. I think I ended up with only 4 tubers off of this clump and another one like it.

Here are the separate little clumps I eventually untangled from the mass above. Much easier to work with, and another testament to dividing every year or two.

It was just guesswork for me to find obvious eyes on this dahlia. It had been out of the ground for a long time. So take a guess and hope for the best. In spring, the heat and light and internal alarm clock will show you if you have got some tubers that will produce growth.

Wow, this is really helpful. Hopefully in a month or so when frost passes I will dig mine up (had in ground 2 winters and havent divided yet) it will look like one of those clumps so i can divide correctly. I really like my dahlia but dont know what type it is. IT is single, and a light autumn orange color. I love it....

Again, thanks for information and pictures (say a thousand words)

Thank you for your kind words. I look back at those photos and it looks like I gnawed some of those tubers off the clump LOL!. A little practice and it will be child's play for you.

You will have to dig up your couple-year clumps to see what awaits you. They can get tougher to divide each year in the ground, so hope for the best.

Want to see a comparison between year 1, 2, and 4-5 of the same variety coming out of the ground? Not all varieties will behave this way, but Chimacum Topaz cannot be stopped.
If you dig in the spring, you might very well find well developed sprouts such as these:
One year in the ground

Two years in the ground, notice I only let a few stalks go on to grow. There would have been others I broke off from all those tubers fighting to grow.

And after several years in the ground, you end up with a complete mess that's very difficult to divide easily.

Those pictures.....Now I am scared, lol! I was before actually.

Can you tell me, is the best thing to put on after I cut them sulfer, or are there other things? Also, do I need to wash in bleach water if only drying the cut a bit and putting back in ground?

As well, I am interested in other types, I like the smaller single ones, is there a good source to get them from?

No idea on the singles. Seeds which are often single flowers are available at many places and are easy to grow. Other vendors have a variety of singles.

Marked with eyes

Marked with where I'd cut. Don't forget to turn the clump upside down to check for eyes associated with tubers on the underside.

One or two cuts from left and right to get these two tubers off the clump. A careful slice between eyes and you'll get two tubers off this "V" shaped offspring.

Eyes marked in red, where I'd make cutting lines in green, brown spot fungus marked in blue. I'll have to use chemistry to kill that in my soil next year.

Notice the stalk is pointing down, so don't forget turn the clump over to get some easily nabbed tubers that may be there.

From last year or 06, marked for dividing. This kind of clump is a real gift: tubers usually only take one cut, are widely spaced, eyes bulging.

Happy dividing.

Thanks for all the information about dividing the tubers.