Byron,

You're right to assume. This does indicate a lack of available nutrients. I've had this before on every garlic plant and amended the bed with premium alfalfa, i.e. horse feed, and all of the subsequent years my garlic plants did not show this. Plus larger bulbs have been harvested since.
I'm growing Spanish Roja, but at the time when my plants were white streaked on the stalks I was growing 'Music'. A soil pH test may also be part as I limed the same year as I tilled in premium alfalfa. (from Purina feeds)

Before I planted last year, I turned in one truckload of well-composted chicken manure and 2 truckloads of well-composted horse manure/shavings. The ground looked like potting soil and was so fluffy that you'd sink down 6 inches when you walked on it.

Everything shot up fast and lush in the fall last year, and then I mulched with wheat and barley straw and weeded a couple of time since. I guess it's possible that it used up most of the nutrients from that, but from what I've read on here, alliums don't need a lot of nutrients towards the end when they're bulbing...

No, not true. They need tons of nitrogen at late winter/early spring when they start to look peeked. I mix bagged chicken manure with composted wood product and a helping of Dr. Earth 4-4-4 granular fertilizer. This year I was sick and injured and did not get out to do my regular fertilizing and I can say it is a very disappointing harvest except for the early varieties which apparently had enough feed at the right time. But my hardnecks are so small as to be unusable for the most part.

Thanks for the info, still_kris.

The Early Italian Red was ready yesterday, so I dug it up:

{{gwi:363667}}

They look about average, probably even pretty good considering the lousy spring we've had. Best roots I've seen for the few years I've been growing garlic.

If you're growing in or near Portland I think you might have jumped the gun a little bit. There is still quite a lot of green on those plants in the picture.
All my garlic (just outside pdx) is at least 2 weeks later than usual. I'm just digging my earliest Turban variety tomorrow. Early Italian is usually ready just a bit later
than German White which is still sizing up now.

Garlic puts on quite a bit of size in the last few weeks of its cycle. If you have any more to dig, try to put it off a little longer (just my opinion).
And also based on my opinion, even though long, cool, wet springs are horrible for heat loving plants, I always find that my overwintering alliums (garlic, onions, shallots) just love it! I'm expecting a great harvest without a drop of irrigation.

madroneb,

Thanks for your feedback.

I guess I'm a little gun-shy after last year's experience of discovering that the Polish White had ruptured underground because of rains late in the growing season. I realize that's not going to be a problem this week (and probably the next), but the other issue is that either gophers, moles or voles have discovered my Asian Tempest and have taken out about 20 plants so far. They always seem to go for the biggest plants, too!

I will wait at least a week and do another "core sample" to check the sizes of things. I have about 2500 more plants to dig...

Damn gophers. I hate em. Sorry to hear they found your garlic.
At my place moles dig through the beds, voles follow them up and eat lots of plants but luckily stay away from the alliums.
Though not entirely organic, sulfur bombs (giant destroyers) do the trick and don't damage the plants.

And yes, the weather is finally working in our favor. The garlic is finishing up without any splitting and my overwintering onions are down and getting ready to be harvested.
Good luck digging all your Garlic!