Replies

1. 
   jonsherryl | Jun 04, 2002 05:51pm | #1

   Dave, this is another one of those common names that is open to rather subjective interpretations. The term "claro" is Spanish and translates as bright, light or clear. In the lumber industry though, claro is sometimes used to simply refer to the wood of the native Californian walnuts (Juglands californica and Juglans hindsii, AKA Hinds walnut) which produce woods that are similar to our eastern black walnut.  Hinds is sometimes used in the orchard industry as a rootstock species for growing the commercial, "English" walnut (Juglans regia.)

   When the English (regia) species is grafted onto the native rootstock (hindsii, or Hinds walnut) the comingled wood tissue that develops low in trunk of the tree tends to have a variegated color and marble-like figure. It makes strikingly attractive gunstocks and this is the material that is usually referred to as "claro walnut"...But the buyer needs to be careful. Unless you have a good working relationship with the seller and have reason to trust that the stock is highly selected and top quality...then this is not a wood you want to buy sight unseen.  To be sure, there's nothing wrong with ordinary Hinds walnut. Actually, none of the walnuts deserve to be called "ordinary" and Hinds often produces attractive figure on its own...so, it's a nice cabinet wood, if the price is right...but it's a world apart from the specially selected, premium stuff.

1. 
   LD | Jun 04, 2002 11:41pm | #2

   Thanks for your quick and learned response.

1. 
   StanleyNiemiec | Jun 05, 2002 12:38am | #3

   Jon:

   Most of the people I have dealt with on the issue of walnut in Oregon seem to feel that the root graft stock is J. nigra (if my memory is still working).  I have got this from several local dealers including Gary Goby and from Ag Extension staff.

   I don't know what goes on in California (who really does anyway) and whether there is sufficient indigenous walnut and it is resistant/suitable for grafting.

   Terms like Claro walnut are dangerous catch-alls in my opinion, and therein suitable justification for indicating on the PO form the specific species you desire.    

1. 
   GregB126 | Jun 05, 2002 01:14am | #4

   NIEMIEC1,

   Our family used to farm walnuts in California.  20-30 years ago, the rootstock used was either "Black Walnut" or "hybrid" rootstock.  It is possible the black was really something else, but we all called it that.  The "we" included the nurserymen and the university types.  Our own place was on black.  A very serious pollen-borne virus known as "blackline" began hitting pretty hard in some areas in the late '70's, especially.  It didn't hurt the english fruitwood, but was put to a halt by the black walnut rootstock, as it made its way from the point of entry (the flowers) down through the tree and into the roots.  This "halt" took the form of a black, necrotic line right at the graft union, which eventually would girdle and kill the tree.  The hybrid was a bit resistant to this, with the line appearing as more of a blur.  Wouldn't kill the tree so fast, but the virus still thrived above and would spread just fine when the pollen was produced.  The two are pretty easily distinguished by eye, as you are hurrying along the freeway trying to pass through our lunatic state.  The black bark is far rougher/coarser than the hybrid, which is itself not quite as smooth as the english grafted to it.  By the late '60's-early '70's the graft unions were pretty close to the ground.  Ours and our neighbors (several hundred acres worth) had unions little more than a foot above ground, anyway never as high as two feet.

   Cheers,

   Greg

2. 
   jonsherryl | Jun 05, 2002 04:28am | #5

   Stanley, they use various species and hybrids for rootstock, depending upon climate and hardiness...and that's why I said: "Hinds is sometimes used..." . I didn't figure it contributed to the point enough to drift off into the miopics of commercial walnut production. I used Hinds as an example because, in the lumber industry, they get a little sloppy with the term "claro" out there and apply it to the wood of Hinds walnut, even if it doesn't display variegated figure.

   You do raise an interesting point though, regarding whether black walnut rootstock interacts with the English scion in the same way as does Hinds or some of the hybrids they use in the orchard business. I suspect it would. The differences between Juglands nigra and Juglans hindsii are rather subtle compared to the differences between any of the American walnuts and the English, or Old World species; Juglans regia. In terms of genetics, I suspect J. regia drifts back more toward our butternut (J. cinerea)...or represents a different tangent from the ancestral stock of all the walnuts, putting it sort of in between our black walnut and butternut. The walnut family, Juglandaceae, is an ancient family with separate relic populations in America, Europe and Asia. Fifty million years or so ago, it played a much more dominant role in Forests worldwide. Unfortunately, it's reproductive strategy isn't very efficient (putting so much energy into large but relatively few seeds that don't lend themselves well to wide dispersion) and this family hasn't fared well...especially during recent Ice Ages.