Looks like an Eastern black walnut, Juglans nigra. You are about on the Western edge of its native habitat; but it grows well all the way to California if it is planted there and given enough water.

The western edge stops at Dallas, according to the only map I could find. Which is about 600 miles away.

All the pictures I find of J. nigra nuts, they have deep ridges in the shell, but mine are smooth.

I am in the native range of J. major and J. microcarpa. I'm hoping that it's one of these, particularly the latter. But can't find anything to help pin it down.

Here is a link that might be useful: J. Nigra range

I'd go with J. microcarpa. The foliage looks very close to several growing in my yard and the keys (e.g., Elias) indicate J. major has fewer leaflets than your sample. I've collected and husked quite a few J. microcarpa fruits and they look like your photos. Generally the nuts are around half an inch in diameter but I've collected them as large as 0.7 inches. My experience with J. major is far more limited but the fruit and nuts on the one tree I saw that was bearing were definitely larger.

Well, maybe one in ten are 5/8" or so. The rest barely fit through a 7/8" hole in the board while I was cleaning them. I think they're maybe too big to be J. microcarpa, but I'm not sure.

They might even be J. microcarpa x major... supposedly they hybridize quite a bit.

Foliage aspect is like that of one of the others besides eastern black walnut. Leaflets probably also different. Don't remember such rough bark on that one, either. We have all different kinds out here, I know only the most prominent species.

I'm suspicious of J.microcarpa, too, but...
I'll bet someone in the Hort department at TTU that can tell you exactly what it is, without us having to guess, based upon photos.

The description of J. major nuts per my source is that they range from 1 to 1.6" diameter, and that the leaflets are 9 to 14 in number (rarely to 19). I don't see that in the photos. On the other hand, J. major fruit is described as having a "small sharp point at the tip" and I do see that.

The hybridization factor--given the overlapping ranges--can really confound the ID. I seem to recall that some botanists have proposed that these two aren't really separate species.

A similar situation is that I've been trying to determine whether a local tree is a pure J. cinerea or a hybrid (25% or less) with J. ailantifolia. To assess this, there are 11 characters in a key developed by Dr. Woeste at Purdue, and even with me having all the plant parts at hand there is still a degree of doubt.

I've emailed my Hort professor and asked... he said "he'd get back to me". My hort advisor was interested to know that the tree was there, but knew less about it than I did. Texas A&M has a guy that specializes in them, but he's never answered my email.

I guess it doesn't matter... either major or microcarpa seems like an ideal candidate for rootstock for me, given my location. And since I've only ever found either (microcarpa) being offered by a nursery in Oklahoma that doesn't do mail order, this was a lucky find. It was literally right outside the window of where I work (I'm an employee and a student).

No idea what to do now. I know I need 90 days of cold for them, so looks like I'll have to find room in the fridge... but I've also read they shouldn't dry out. Best I can figure is to put them in a ziplock with some damp sand. I've tried using damp paper towels before for other seeds, but that tends to mold up too much. Does anyone have any recommendations?

And supposing I do get them to sprout and grow for a couple of years... where in the heck can I even get scion? The only place I've ever seen walnut scion is this one nursery in Kentucky, but with Tennessee having just discovered Thousand Cankers, I'm concerned that might not be a good idea.

Maybe I should've stuck to pecans...

You could plant them outside now and cover with hardware cloth to prevent predation. I usually keep them dry in the fridge until starting cold/damp stratification around mid-November. I keep the seed in wetted down vermiculite with all the excess moisture squeezed out of it. I rarely see radicle emergence before four months elapse. You should check for mold from time to time. I've used dilute hydrogen peroxide or bleach solution to address this, also sometimes Captan. Spring germination % has varied from year to year all the way from 20 to 80%, partly depending on the tree.

On the hybridization angle, have you checked the immediate vicinity to see what other Juglans spp. are present?

Do you know for sure whether J. microcarpa is resistant to thousand cankers? J. major is minimally affected but I thought the jury was out on J. microcarpa. Sure hope it's resistant. What sp. scionwood are you hoping to graft?

I'm afraid our outdoor weather is too inconsistent... air temps might not get below 40 until January, it all depends.

I have checked all over campus... I haven't noticed one other walnut anywhere. Though, checking today, it looks like this one has a sprinkler, which might account for doing well through the drought. No reason to expect the smallest nuts.

As for thousand cankers, I've read hints that microcarpa is more resistant than other species, but whether this means it takes two more years to croak or nearly full immunity, I know not.

As far as scion, I was hoping to get one or two nice carpathian/english cultivars suited for the region. Maybe a heartnut and/or butternut? I don't really know. These would all be for personal use, of course. I'd give away any excess.

Any recommendations?

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Posted by bboy USDA 8 Sunset 5 WA (My Page) on
Thu, Oct 20, 11 at 9:50

Foliage aspect is like that of one of the others besides eastern black walnut. Leaflets probably also different. Don't remember such rough bark on that one, either. We have all different kinds out here, I know only the most prominent species.
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Yes, the bark seems very rough for a B walnut -- more like butternut, except that butternut's bark-color is usually more light-gray. And the foliage has the more coarse-like butternut look. But the nuts look like B walnut..

Prb'ly some difficult/impossible-to-identify hybrid.

It doesn't help that some articles (research?) state J. californica is susceptible to TCD and others say it's as resistant as J. major. I have read that J. cinerea is resistant to TCD, but with it you have to be concerned about Sirococcus canker (but at least you have isolation). And J. ailantifolia? Probably too early to know for sure on any of these spp.

I don't know anything about the grafting compatibility of the various spp. If J. regia is compatible, it seems like you might have a wide range of choices for scionwood. The Carpathian variety was selected for cold hardiness and for not waking up too early, factors that may be unimportant at your location.

Good luck and keep us informed of your project over the years.

Thank you, and I'll definitely let people know it all turns out. If anyone is interested in having seed from this tree, I may be able to provide that every September/October. Just in case anyone stumbles across this post a couple years from now.

nomorenicks,
TCD's been documented in the Knoxville TN area, but I've not seen any reports of it farther west - like where Clifford England is located(I'm presuming that's where you've seen the list of available scionwood - and he's got a good collection of BW, Carpathian, heartnut, etc.). So far as I know, he'd be a safe source - but ask him, he'll tell you straight up.
Nebraska Nut Growers Assn. used to offer scionwood of a few superior BW varieties, in addition to northern pecan and hickory.
The National Clonal Germplasm Repository at Davis CA has offered some walnut scionwood in the past, but they may have shut down shipments, due to concerns over TCD.
Wes Rice, in OK, may have some Persian/Carpathians that'll work in TX - along some of the TAMU nut folks, he'd be a good contact to make - and can probably offer some good suggestions of varieties that may work for you.

Black walnut is a suitable rootstock for any/all of the walnut species - I've grafted Persian/Carpathian, butternut, heartnut onto eastern black walnut, with no apparent incompatibility.
I have more difficulty getting successful grafts of any of the walnut species, compared to pecan/hickory/oak. They just don't 'take' for me with the success rates I get with the other hardwoods, for whatever reason.

Thanks Lucky. Yeh, I think it was England nurseries, it stuck out because though I've found places to order scion for many other fruit trees, that was the only place I've ever seen walnut.

I know about the Davis repository, but I was under the impression that was for researchers only. Then again, I am a hort major... haha. I was going to try and see if they'd send some pistachio scion once my seedlings are large enough.

Didn't know about Nebraska Nut Growers, thanks for the tip. I keep a list of seed/plant/bulb/livestock sources... I'll have to add that later tonight.

Oklahoma/Nebraska cultivars seem like they'd be ideal for here... I'm only 3 hours away from the panhandle.

Also, what oaks are worth grafting? I've been wanting to try to grow a cork oak or two, and I have a half-assed idea that I might manage to grow acorns as a primary feed for hogs, but I wasn't aware that anyone ever bothered to graft them.

While you're at it, check out the Northern Nut Growers Assn. website - they have 'Marketplace' and 'Scion Trade/Swap' pages, in addition to links to state/regional nutgrowers associations that might have some of the stuff you're looking for. And lots of good information!
I've accumulated over 30 varieties each of pecan and hickory, mostly from trades, inexpensive purchases, or shared material from other nut-growing enthusiasts around the country. We all like to share - and if we get stuff distributed out to alternate sites, if we lose a selection, it's not 'gone forever'.

Oaks - grafting works great with members of the white oak group - no incompatibility issues that I'm aware of, though some(like Q.stellata) don't make great rootstocks, 'cause they're so slow-growing. Bur oak works best for me as a rootstock, 'cause it's readily available, adaptable to a wide range of soil types, and grows vigorously. (white)Oaks are just about as easy and successfully grafted as pears/apples, but timing of graft placement is a little more critical.
Peroxidase enzyme incompatibilities make grafting members of the red/black oak group problematic, even when a selection is grafted onto its own seedlings.

I originally got into oaks for wildlife mast production, then got hooked up with some folks who were making selections for low tannin levels, as a potential human food crop. Most of my cultivated stuff is bur oak, swamp white oak, and various hybrids of white oak species.

There are some oak cultivars in the nursery trade, like 'Crimson Spire' that are propagated by grafting/budding, as they don't come 'true' from seed.

I've never had issues getting material from NCGR - I do have university agriculture dept. affiliation, but I'm not involved in horticulture/agronomy research. Do think you have to provide a FedEx or UPS account number for them to bill shipping charges to - but it's been several years since I got anything from them; that may have changed.

nomorenicksleft - email me off-list for more specific discussion and proposals.

nomorericksleft, if you are still able/willing, I would be grateful for seed from this Juglans tree. I am interested in thousand-canker-resistant Juglans that might do well in my area (Boulder, CO), and this tree's seeds might be good ones to try. Thanks!