This posting is for GallopingCamel, who wanted something a bit lighter ;-)
Today I took a field trip. All the way to Palo Alto. The Stanford Shopping center.
I grew up in an area that grew walnuts, among other things, and as a kid pulled my Little Red Wagon all around town collecting walnuts. For a Gunnysack full, we got something like 50 cents (think $5 today) for Black Walnuts and it was several dollars for a sack of English Walnuts. ( I don’t remember the exact price for them, as there were never enough to collect a whole bag. At least not for a kid with a wagon… the adults having creamed off the expensive nuts.)
So I’ve spent a fair amount of time climbing in walnut trees and even more cracking and eating them. Oh, and cleaning all the walnut stains of fingers, hands, legs, whatever.
Eventually we moved to a house that had a walnut tree in the yard. Then we had more walnuts than we could ever want, and English Walnuts too; but by then I was washing dishes in the family restaurant and making more money faster than picking up walnuts. And my hands were cleaner at the end of a shift than at the start too ;-) (In those days dishes were all washed by hand. A 60 seat restaurant and we’d turn over each seat several times. I’ve washed a lifetime of dishes…)
So I thought I knew what a Walnut Tree was. Giant things.
Notice the tiny house in the lower right corner… It is 2 stories tall. The tiny vertical dark smudge just to the right of the trunk is an adult person. Click the link to get a full resolution version and expand it to see the person clearly.
I’ve hankered after one … or sometimes a Pecan Tree… there was ONE near my home as a kid and we’d sometimes get buckets of free pecans. Loved to eat them, but there was no local market for collected bags as there were not enough trees.
But my lot is small here. Some of these trees are 44 m or about 144 feet tall and can spread to 75 feet for pecans, or 144 feet for that record walnut tree. Plant one in the exact middle of my lot and it would reach to the far side of the lots on each side of me, and from front to back of my lot with more left over…
So I despaired of having a walnut tree.
Yes, I could plant a young one and let it be the problem of someone else (as I’m not going to live long enough to grow a record walnut tree – that takes generations). But that just means the tree would be cut down by someone else just as it was becoming a nice sized tree.
Then I discovered there was a native walnut in California. Actually, two of them that are slightly different. One has a full trunk and is a medium sized tree, the other is often a multistemmed shrub like tree. Looking into it, the nuts are smaller and with much harder shells. (As though the black walnut was not already hard enough to crack!). So not grown commercially and probably not all that attractive even for home use. Still, it is a walnut…
Encyclopedia of Stanford Trees, Shrubs, and Vines
Juglans californica hindsii. CALIFORNIA BLACK WALNUT. Central California
JUGLANDACEAE (Walnut family)
Closely related to a shrubby species which is widely distributed in Southern California, the black walnut is an erect single-trunked tree that hindsii is found in nature only on a few sites of Indian habitation (including Jasper Ridge), which makes one think that it may be a product of human selection. The numerous leaflets are quite unlike those of English walnut in general appearance, being lanceolate and 3 inches or so in length, with fine teeth. The bark is dark and rough and has a noticeable smell when abraded. The nut is smooth and hard and is embedded in a thick green husk that will stain the fingers. A large specimen grows at 541 Los Arboles Avenue, and many more are in the Sand Hill Road greenbelt, opposite the Stanford Shopping Center. In Palo Alto it can be seen at 950 Boyce Avenue.
The Juglans Californica (unadorned) is found mostly in the southern half of the State. So there is some quibble of the question of if Hindsii is a natural Northern California variation, or as noted in the article, a human selection. A paper down below sorts it out.
But noticed that phrase “shrubby species”… A “walnut shrub”!
A fairly narrow range for the Shrubby One.
Sort of on my “to do list” is to find a stand of Juglans Californica and collect some walnuts and start a few, eventually to plant one out (somewhere) once I’ve cleared a spot in the yard for it. But might the Hindsii work? Hmmm…
So off I went to inspect the specimens in Palo Alto listed in that article.
What I noticed most was that the bark was very thick and very coarse (deep furrows). These trees have evolved to deal with fire in California. Around the very base is an even thicker ring. It looks like the bottom foot or so is especially thickened to resist grass fires. That it lives in the wild in California (even if mostly in riparian areas) means it is somewhat drought adapted. So ‘watering optional’. A nice feature.
Along the way I looked up walnuts and discovered there is a VERY large list of different walnuts. Who knew? Very much not just the two kinds I grew up with. One caveat though: The Californica will easily hybridize with the other black walnuts. That is already a threat to some of the wild stands, as some hybrids are found in the wild. So many of the “Black Walnuts” on this list ought to be seen as local varieties of a species, rather than different species. Yet the “species barrier” is really more of a “species strong suggestion”… so perhaps treating them as “different species, just ‘friendly’” is more appropriate ;-)
OK, from the wiki, a list of different walnut types, just to illustrate the point:
The genus Juglans is divided into four sections.
Sections and species
Juglans sect. Cardiocaryon. Leaves are very large (40–90 cm), with 11–19 broad leaflets, softly downy, margins serrated. The wood is soft, and the fruits borne in racemes of up to 20. The nuts have thick shells. The origin is in northeast Asia.
J. ailantifolia Carr. (J. cordiformis Maxim., J. sieboldiana Maxim.)—Japanese walnut
J. ailantifolia var. cordiformis—Heartnut
J. mandshurica Maxim. (J. cathayensis Dode, J. formosana Hayata, J. hopeiensis Dode, J. stenocarpa Maxim.)—Manchurian walnut or Chinese walnut
Juglans sect. Juglans. Leaves are large (20–45 cm), with 5–9 broad leaflets, hairless, margins entire. The wood is hard. The origin is southeast Europe to central Asia.
J. regia L. (J. duclouxiana Dode, J. fallax Dode, J. orientis Dode)—common walnut, Persian, English, or Carpathian walnut
J. sigillata Dode—iron walnut (doubtfully distinct from J. regia)
Juglans sect. Rhysocaryon (black walnuts) Leaves are large (20–50 cm), with 11–23 slender leaflets, finely pubescent, margins serrated. The wood can be extremely hard (Brazilian walnut Janka hardness test of 3684). The origins are North America and South America.
J. australis Griseb. (J. brasiliensis Dode)—Argentine walnut, Brazilian walnut
J. boliviana (C. DC.) Dode—Bolivian walnut, Peruvian walnut
J. californica S.Wats.—California black walnut
J. hindsii (Jepson) R.E.Smith—Hinds’ black walnut
J. hirsuta Manning—Nuevo León walnut
J. jamaicensis C.DC. (J. insularis Griseb.)—West Indies walnut
J. major (Torrey) Heller (J. arizonica Dode, J. elaeopyron Dode, J. torreyi Dode)—Arizona black walnut
J. major var. glabrata Manning
J. microcarpa Berlandier (J. rupestris Engelm.)—Texas black walnut
J. microcarpa var. microcarpa
J. microcarpa var. stewartii (Johnston) Manning
J. mollis Engelm.—Mexican walnut
J. neotropica Diels (J. honorei Dode)—Andean walnut, cedro negro, cedro nogal, nogal, nogal Bogotano
J. nigra L.—Eastern black walnut
J. olanchana Standl. & L.O.Williams—cedro negro, nogal, walnut
J. olanchana var. olanchana
J. olanchana var. standleyi
J. peruviana Dode—Peruvian walnut
J. soratensis Manning
J. steyermarkii Manning—Guatemalan walnut
J. venezuelensis Manning—Venezuela walnut
Juglans sect. Trachycaryon. Leaves are very large (40–90 cm), with 11–19 broad leaflets, softly downy, margins serrated. The wood is soft. Fruits are borne in clusters of two to three. The nuts have a thick, rough shell bearing distinct, sharp ridges. Origin is in eastern North America.
J. cinerea L.—Butternut
Roughly Asian, European, and American walnuts. With several distinct types in Latin America and even on Caribbean Islands.
Oh, and some species x species:
J. × bixbyi Rehd.—J. ailantifolia x J. cinerea
J. × intermedia Carr.—J. nigra x J. regia
J. × notha Rehd.—J. ailantifolia x J. regia
J. × quadrangulata (Carr.) Rehd.—J. cinerea x J. regia
J. × sinensis (D. C.) Rehd.—J. mandschurica x J. regia
J. × paradox Burbank—J. hindsii x J. regia
J. × royal Burbank—J. hindsii x J. nigra
So on the one hand I’m fond of the idea of preserving some endangered California walnut type in my yard. On the other hand, some of those crosses might be both small AND have nicer easier to open nuts… Like those Hindsii x Regia crosses…
We have squirrels in the neighborhood. I like watching them play and enjoy their antics.
I also like knowing there’s a nice supply “on the hoof” if “the fall happens”… BUT, I had a cherry tree for a couple of decades and got all of a few handfuls of cherries. Apples? I get some, the squirrels get more…
For ill explainable reasons, we have the Eastern squirrel.
The eastern gray squirrel has been introduced to a variety of locations in western North America: in Canada, to the southwest corner of British Columbia and to the city of Calgary, Alberta; in the United States, to the states of Washington and Oregon and, in California, to the city of San Francisco and the peninsula area of San Mateo and Santa Clara counties, south of the city. It has become the most common squirrel in many urban and suburban habitats in western North America, from north of central California to southwest British Columbia. At the turn of the 19th to 20th century the eastern gray squirrel was introduced into South Africa, Ireland and England.
So this is what I frequently see looking at me from the trees, the fences, the rooftop, the yard (often with an apple in mouth, trying to figure out how to carry something bigger than it’s head, and get back up the fence) and occasionally from on top of the Seed Archive Freezer on the patio (no doubt plotting how to get to the seeds inside …)
Though that one is living in Kensington Gardens in the UK. (One can only wonder why the American Eastern squirrel is living in both California out west and in the UK. We have our own native ground squirrel, that makes burrows in the ground, and the UK has a native Red Squirrel. Then again, the Gray comes in colors from brown to black; so sometimes I have black ones looking at me and sometimes brown…)
My hope would be that the Eastern Squirrel is adapted to the Eastern walnuts, that have thinner shells and grooved shells that teeth can get purchase on much more readily. And maybe, just maybe, they would be thwarted by a nut that can stand up to California Ground Squirrels who can tunnel through dry near concrete like adobe soils…
Hey, a fella can dream, can’t he?
I’m quite sure that a pecan tree or even a walnut tree is going to be one heck of a
But I’m not all THAT interested in being “servant to squirrels”…
So perhaps those harder shells on the Californica might be a ‘feature’ ;-)
That Stanford page has an interesting view on Squirrels:
Walnut, pecan, and oak trees benefit when squirrels eat their nuts and acorns because the squirrels do not find all of the nuts that they so assiduously bury; some of the nuts germinate, contributing to the next generation of trees. Today we are the beneficiaries of millennia of unconscious plant breeding by squirrels that have selected for tasty kernels and thin shells; but the shells of the black walnut could still use more genetic help. In the Southern Hemisphere, by contrast, macadamia nuts and Brazil nuts developed formidable armor, especially the Brazil nuts, which are not only resistant to cracking with the teeth but are also enclosed, several at a time (up to 20 or so), in a tough woody coco weighing up to 5 pounds.
So South America needs more squirrels (or less of the nut eaters with super teeth…) and perhaps the native California walnuts would be a bit less attractive to the squirrels I’ve got.
There is a commercial on TV here for Post-it Notes. It has a squirrel returning to a hole in the tree. Inside the whole thing is lined with notes on where nuts have be buried. Reading the above, I find I’m happy that squirrels have less than perfect memories and that the nut trees have benefited from the selection process.
Back At Nuts
So now I’m torn between a desire to search through ALL the different types of walnuts, looking for the optimal solution (perhaps some South American Walnut that can stand up to whatever eats Brazil Nuts?), a desire to find out if we have any non-Grey squirrels near here and see how they compare (perhaps they could be encouraged to ‘argue’ with the grays?) and a desire to just plant a “shrubby walnut” just to see what happens.
From the Juglans wiki:
The best-known member of the genus is the Persian walnut (J. regia, literally “royal walnut”), native from the Balkans in southeast Europe, southwest and central Asia to the Himalaya and southwest China. Walnuts are a traditional feature of Iranian cuisine; the nation has extensive orchards which are an important feature of regional economies. In Kyrgyzstan alone, there are 230,700 ha of walnut-fruit forest, where J. regia is the dominant overstory tree (Hemery and Popov 1998). In non-European English-speaking nations, the nut of the J. regia is often called the “English walnut”; in Great Britain, the “common walnut.”
The eastern black walnut (J. nigra) is a common species in its native eastern North America, and is also widely cultivated elsewhere. The nuts are edible, and though they are often used in expensive baked goods, the Persian walnut is preferred for everyday use because it is easier to extract the nutmeat. The wood is particularly valuable.
The Hinds’ black walnut (J. hindsii) is native to northern California, where it has been widely used commercially as a rootstock for J. regia trees. Hinds’ black walnut shells do not have the deep grooves characteristic of the eastern black walnut.
Japanese walnut foliage and nuts
The Japanese walnut (J. ailantifolia) is similar to butternut, distinguished by the larger leaves up to 90 cm long, and round (not oval) nuts. The variety cordiformis, often called the heartnut has heart-shaped nuts; the common name of this variety is the source of the sectional name Cardiocaryon.
The butternut (J. cinerea) is also native to eastern North America, where it is currently endangered by an introduced disease, butternut canker, caused by the fungus Sirococcus clavigignenti. Its leaves are 40–60 cm long, the fruits are oval, the shell has very tall, very slender ridges, and the kernel is especially high in fat.
First off, that English Walnut is really a Persian Walnut. OK… (The story is that when folks came to America, they called the local walnuts Black Walnuts, and named the “common” walnut of England, the English Walnut, even though England had picked them up from Persia some hundreds of years before).
The Japanese walnut is like a “butternut”, but the US Butternut is endangered by a foreign fungus. Oh Dear!
So should I try to get a clean American Butternut and grow it out here in the west, hopefully well away from that foreign fungus, as a butternut preserve?
It is a deciduous tree growing to 20 m tall, rarely 30 m, and 40–80 cm stem diameter, with light gray bark.
60 to 90 feet. Oh Dear!
So back at the Shrubby Guys…
Juglans californica, the California black walnut, also called the California walnut, or the Southern California black walnut, is a large shrub or small tree (up to 30 feet tall) of the Juglandaceae (walnut) family endemic to California.
That 30 feet tall is a whole lot more attractive on a small lot than the 30 meters tall… or 44 meters… and that’s an “up to” 30 feet. I’m liking this “walnut shrub” idea…
J. californica is generally found in the southern California Coast Ranges, Transverse Ranges, and Peninsular Ranges, and the Central Valley. It grows as part of mixed woodlands, and also on slopes and in valleys wherever conditions are favorable. It is threatened by development and overgrazing. Some native stands remain in urban Los Angeles in the Santa Monica Mountains and Hollywood Hills. J. californica grows in riparian woodlands, either in single species stands or mixed with California’s oaks (Quercus spp.) and cottonwoods (Populus fremontii).
So I’ve got to go south a few hundred miles, climb around on some slopes with creeks in them, on dry mountains (likely on fire right now, this being the end of summer…) and work my way through stands of oaks (perhaps I can collect some acorns and try out my
Indian Native American skills at making acorn porridge…) and working through Cottonwood thickets while looking for any nuts that the squirrels might have missed… whenever these things make nuts… I wonder if it is the same time as other walnuts? Sometimes California Natives run on odd schedules…
Oh, and avoiding all the poison oak at the same time.
The hills here are often full of poison oak.
For those not familiar with it, the Populus Fremontii is not tall and slender like the Italica type. It’s a large full spreading tree. It does pop up overnight and grow to large size while you are at work, so planting one before taking a long vacation is a bad idea, lest you come home to a minor forest… ;-) They also have the characteristic poplar / cottonwood smell. Sort of pleasant for the first year you have one. After a decade, not so much.
I’ve seen them larger than this, and in very dense groves with thick forest litter. They often grow along rivers. They propagate in part by having limbs that break off, float down river and root where they make landfall. I’ve seen fences made from round posts of cut up limbs that then all sprouted into new trees. Some folks do that deliberately. Others “discover” it. Pruning one of these, do not leave limbs in contact with wet ground…
But I digress…
Back at Californica:
Juglans californica can be either a large shrub with 1-5 trunks, or a small, single-trunked tree. The main trunk can fork close to the ground, making it look like two trees that have grown together, then diverged. It has thick bark, deeply channeled or furrowed at maturity. It has large, pinnately compound leaves with 11-19 lanceolate leaflets with toothed margins and no hair in the vein angles. It has a small hard nut in a shallowly grooved, thick shell that is difficult to remove.
Like the size. Not so keen on the idea of very small rewards after a lot of work. Regular old black walnuts are very hard to open compared to English, er, Common, er, Persian walnuts… Making them even harder? Hmmmm….
The Hindsii, though a bit larger, are already “in the area” (though likely to take more looking to find some growing wild, as much of this ‘turf’ is now under houses or farms, but easier to find in urban preserves).
Though there is this paper by a guy from Oregon with pictures of him standing next to a Hindsii in Oregon… so he thinks the range ought to extend that far up, seeing as the trees are there. But the consensus is that they are not there. So officially the range does not include Oregon. Maybe I'll go get an Oregon seed and plant a tree that doesn't exist? Hmmmm….
Oddly, further down in that paper it has pictures of the nuts of Californica (unadorned) and Hindsii (which he calls Hinds not liking Latin so much I guess). The “shrubby” one (that he calls “California black”) has much smaller nuts that then Hinds. Maybe I ought to try opening and eating a few seeds when ‘collecting’ them before committing to growing a tree. Having a “shrubby” walnut is not as much fun if the nuts are dinky, hard as rocks, and have not much in them. Decisions decisions…
But wait, there’s more… it might be a ‘living fossil’. Seems they have fossilized walnuts in the area that look like the same ones.
Paleobotany—Is Hinds Walnut a Living Fossil?
As Thomsen (1963) pointed out, Jepson (1910), Griffen and Critchfield (1972) failed to consult the paleobotanical records of walnuts in western North America. The fossil record at the John Day Fossil Beds in eastern Oregon indicates the presence of silicified walnuts in the Clarno Formation of Juglans clarnensis Scott, dated in the Middle Eocene (49 to 41 million years ago). This small walnut, the earliest confirmed Juglans fruit known (Scott 1954), is nearly indistinguishable from J. hindsii. This is significant because in Juglandaceae, the most important structure for generic level determinations is the fruit: “Each modern genus is defined such that it can be recognized on the basis of its fruit, with or without information from other organs”
There’s a whole lot more in the paper. One bit that caught my eye was the relative freeze resistance of the two walnuts in question. Usually that means one is NOT just a ‘selection’ of the other and it casts doubt on the ‘Indians Selected Them’ theory. Oh, and it determines which ones grow in the UK too:
In Oregon, only two walnuts from North America survive east of the Cascades: eastern black walnut (which rarely produces nuts in the Bend area due to severe spring freezes that damage the catkins and flowers) and butternut (Juglans cinerea). Both of these walnuts also perform well west of the Cascades. The following walnuts are hardy in the major valley systems west of the Cascades: Hinds walnut, Nogal or Arizona walnut (Juglans major) and little walnut (Juglans microcarpa) which ranges as far west as New Mexico. California black walnut, a very tender species, freezes out in the Rogue Valley, but might be grown at Brookings. It is not hardy in the British Isles, although Hinds walnut thrives there (Bean 1978).
So now I’m thinking that I could get seeds of a tree that doesn’t exist from a place where it’s a living fossil and grow them. Never mind that it is identical to the local ones… just think of the story! “There’s ALWAYS a story. -E.M.SMith” ;-)
But I note in passing that there are butternuts growing up there too. So I could get one of them without needing to go all the way “back east” and they are likely fungus free too… Then again, if there is already a refuge population being grown, I don’t need to do it. Decisions decisions…
Then there is that “little walnut” the “microcarpa”. Didn’t notice that before. Hey, I’m in the market for a small walnut…
Juglans microcarpa, known also as the Texas Walnut, Texas Black Walnut or Little Black Walnut (as it belongs to the “black walnuts” section Juglans sect. Rhysocaryon), is a large shrub or small tree (10–30 ft tall) which grows wild along streams and ravines in Texas, New Mexico, Oklahoma, and Kansas. It produces nuts with a width of 1/2—3/4 in. The pinnately compound leaves bear 7—25 untoothed to finely-toothed leaflets, each 1/4—1/2 in wide. It is found at elevations ranging from 700 ft to 6700 ft
Oh Dear! I don’t think I can bring myself to tell the Texans that they have little nuts…
How embarrassing for folks always bragging about how big things are down there…
in Texas, I mean…
But it is just 10 to 30 foot tall. It is a ‘shrub’ sized. But nuts only 1/2 inch wide? Those are mighty tiny nuts. I think I’ll stick with the Hinds instead of the tiny nuts. I’d rather say I got some Hinds at home than say I had little nuts from Texas…
OK, I think I’m settled. It’s going to be a collecting trip to Oregon. Whenever they are ripe and ready. Or if I’m lazy I’ll just stop at a sediment wash near here and collect a Hinds and say I got some in Oregon…
How About A Threesome?
But wait, there’s more!
Many “dicotyledon” plants (2 parts to the seed / leaves) will produce the occasional “tricotyledon” with seeds in thirds and three leaves per junction. It isn’t all that uncommon, and some species more than others.
OK, it’s time that you all got an education on that subject. There are two kinds of seedlings. One is monocotyledon and the other is dicotyledon. Both words will be found in your standard dictionary. Cotyledons are the first leaves to emerge from the seed. Usually, they are very much unlike the second set of leaves which are called true leaves. Deviation from the normal is not common and in many cases is fatal. For example, a 3-lobed walnut or hickory nut is not uncommon but those seeds can never grow. It’s Nature’s way of not allowing her mistakes to continue.
But I think that’s pessimistic! I’ve grown tri-cot seeds before. Not walnuts. It was in college and I was, er, um, nevermind… but it grew and had 50% more greenery per stage, with three leaves instead of two. BTW, this same author goes on to point out his efforts growing tri-cot tomatoes:
We’ve already established that it is a fixed recessive gene in my variety. With time, I am certain that it would become a dominant gene and to the point where a normal dicotyledon seeding would be culled as being inferior. There has been only one tricotyledon study made and that was 80 years ago and with an indeterminate variety. It’s never been researched with a determinate type until now. Four generations of mine has produced tricotyledons. Seed only saved from those plants. I fully expect 1 in 12 seeds to produce a seedling with an extra cotyledon. However, all of the seed that has been sent out this year is unproven as to the percentage of tricotyledons. It would disappoint me if everyone didn’t end up with at least one or two per packet.
Also, long long ago, about 1960, I bought a bag of walnuts at a local fruit stand “back home”. They had shells in 1/3 rds and nuts with three sections. I don’t see any reason to presume these would not grow like all the other tri-cots I’ve ever planted.
So if I really really wanted something cool, I could wander the valleys of Oregon, looking for a “three-way Hinds” and then grow it out at home (heck, doing a graft if I had to) and then I could have a plant that doesn’t exist, that’s a living fossil, of a tri-cot that can’t be. Now that would be something… And boy would it be a story to tell under a tree in the fall as the “three-way Hinds” nuts were ready. And not a tiny Texas nut in sight… Even if it does sound like a Texas Tall tale. Or maybe the tails in Texas just seem tall ’cause the nuts are short? Hmmmm…. decisions decisions…
I think I’ve got some field work to do to answer some important questions. ;-)