Knot a potato?

August 2, 2009 8:29 AM

GardenFilter: We just harvested some potatoes and came across these potato-like knot things. We found about five or six in a bed that hosted both potatoes and garlic, though they were found kinda far from the garlic and well under ground—at least four inches. What are they?

Cut-up old potatoes, and babies from last year's harvest that we cellared, were what we seeded with. We grow organic and did get a slight case of the potato bug, but again, not sure it's relevant

Inside they have the consistency of a potato or a root. Didn't see them obviously attached to a plant. Thought about them being garlic heads but they seemed too deep when we found them, and they're more solid than a garlic seed head, unless it fused together.

I joked with my wife that maybe they're truffles, and while I really doubt that, I wouldn't rule out a fungus of some kind.

Anyone else ever find these?

posted by Toekneesan to home & garden (17 answers total)

They look like root knot nematodes, a soil parasite that infects members of the nightshade family. Some more info on root knot nematodes.
posted by electroboy at 8:43 AM on August 2, 2009 [1 favorite]

I think electoboy's got it. I've had them on my tomatoes but never on the potatoes. Now I'm curious as to whether there are nematodes specific to different types of solanaceae.
posted by X4ster at 9:46 AM on August 2, 2009

Here's a picture of a slice in one. My wife is convinced it's a truffle citing this picture. It does smell a lot like a fungus but we enrich our soil with used mushroom compost.
posted by Toekneesan at 12:55 PM on August 2, 2009

You're right about how truffle-like it looks, I've bought white truffles at the Portland farmer's market and that's exactly how they looked when sliced.
posted by TungstenChef at 1:28 PM on August 2, 2009

Truffles have a different texture than potatoes. Truffles also grow under oak trees (or elm, chestnut, willow, and pine). I wouldn't rule it out without actually touching/smelling them but I doubt they're truffles, based on your description.
posted by cooker girl at 2:03 PM on August 2, 2009

Did it smell amazing when you cut into it? Was the aroma intense at first, but somewhat short-lived? You might have white truffles on your hands... (lucky you!)
posted by danny the boy at 2:08 PM on August 2, 2009

Scroll down to the bottom of this page for a photo of shaved white truffle. The more I think about it, the more annoyed I am that there are people in this world that just HAPPEN TO HAVE TRUFFLES GROWING IN THEIR YARD
posted by danny the boy at 2:13 PM on August 2, 2009

It smells earthy when we cut into it.
posted by Toekneesan at 4:52 PM on August 2, 2009

I don't think anybody can positively ID that as a truffle without smelling it. It looks just like one, and if the smell is "earthy" or "mushroomy" that doesn't rule it out. Nothing smells quite like a truffle though, and anybody who's eaten them can probably tell you right away if that's what they are. My suggestion would be to put them in a small container in the fridge with a cup of arborio rice (it'll keep them dry and will absorb their aroma), then call your favorite local (upscale) restaurant. Tell them that you have an odd request, that you think you found some truffles, and you'd like to have the chef ID and prepare them for you, if that's what they are. A chef worth their salt would jump at the chance, and you might get a very special dinner. Do it quickly though, truffles lose their flavor within days of coming out of the ground.
posted by TungstenChef at 6:22 PM on August 2, 2009

The other thing is that there are a lot of truffles out that that aren't particularly good to eat. None of them are poisonous (that we know of) but only a few species are considered delicacies. On top of that, unless your truffles happened to be ripe when you dug them out, they might not taste as good, and by that I mean smell as strong.

More info at the North American Truffling Society website.

But yeah, no one can ID for you over the internet, and it's odd that they weren't near a tree.
posted by danny the boy at 9:56 PM on August 2, 2009

If it walks like a truffle, and it quacks like a truffle...
If you have no truffle experience, have someone id them for you. Earty and mushroomy are, as tungstenchef points out, definitely two adjectives that describe well the truffle aroma, "intense" would be another, with "awesome" a close fourth.

With two pictures they're not easy to identify, but definitely look like them. If you dug them out before ripening, they might be not as powerful.
My main doubt, though, is that white truffles usually ripen and are dug in the fall/winter, say oct. thru dec.
posted by _dario at 2:36 PM on August 3, 2009

A mycologist friend called them Deer Truffles based on the pictures. I'm meeting with him sometime this week for confirmation and more information. More soon.
posted by Toekneesan at 5:38 PM on August 3, 2009

My mycologist friend is Bill Russell, author of this book. He's pretty sure they are Deer Truffles but he's taking them to a friend specializing in truffles to confirm and maybe figure out a species. In the past couple of days the scent has gotten significantly stronger, but kind of a bit like turpentine. Only a hint of what I remember truffle oil smelling like.

The bad news: according to Bill they're not all that tasty. They're not poisonous but not they're particularly edible and wouldn't have the same flavor as those fetching as much as $4,000 a pound.

If I hear anything more from the folks in the mycology lab I'll be sure to post it. I've sent them some samples through Bill. He seemed intrigued by the fact that they were growing in our garden, rather than under a hemlock tree which is much more common. It prompted a call to the Mushroom Research Facility here at the Penn State campus, as that's where I get the mushroom compost I've been using in my garden. We called to see if they were experimenting with truffle propagation as that might have been an explanation, but alas they aren't. But now they too are awfully curious about how they showed up in my potato bed.
posted by Toekneesan at 12:43 PM on August 5, 2009

What a great mystery. And there aren't ANY trees near your garden? Please let us know about any developments.
posted by danny the boy at 11:19 PM on August 5, 2009

I wrote more about what I discovered here on my flickr stream.

Seems there was a tree in the vicinity that could be involved. The truffles have been identified as either Hydnotrya tulasnei or perhaps some species of Rhizopogon. Neither particularly known for their nom-nom-ness.
posted by Toekneesan at 9:12 AM on August 7, 2009

In the past couple of days the scent has gotten significantly stronger, but kind of a bit like turpentine.

Neat, I guess it makes sense that a pine tree truffle would smell like turpentine, since that's where turpentine comes from.
posted by electroboy at 11:15 AM on August 7, 2009

Er, pine trees, not truffles.
posted by electroboy at 11:15 AM on August 7, 2009