[masraum]

I thought this was interesting. Below is a picture of walnut trees. The poster of the photo wanted to know why the trunks looked the way they did.



Some of the responses had some really interesting information.

(compilation of several responses from the thread, not all from the walnut farmer)

(Walnut farmer) Black walnut rootstalk grafted to an english walnut. The black walnut rootstalks are more disease resistant. Newer trees are typically planted on paradox rootstalks it is a black walnut english walnut hybrid. It isn’t as noticeable of a graft line, but they grow much quicker.

A lot of your fruit trees even your roses are planted on a hardy rootstock and grafted to the desired plant. It is just super noticeable with the walnuts.

Comments re grafts are correct. In the old days indigenous black walnuts were planted by seed and “top worked” to graft the scions of the more desirable English (more appropriately Persian) walnuts which were more palatable and much easier to process. More recently trees are field grown in nurseries and grafted much closer to the soil line so the graft is not as visible. Indigenous rootstocks were more adapted to soil conditions and disease resistance, hence the combo. Not a farmer but 50 years as a nurseryman and arborist. FYI that as stated the black walnut wood is very valuable for art, gunstock and veneer…

Black walnuts are for people who drink Guinness. English walnuts are for people who drink Bud Light… very weak flavor.

the black walnuts are crazy tough to crack… no easy way to harvest those. But their wood (they grow wild around lots of Oregon) is gorgeous… the old black walnut husks were put into the livestock drinking water as it could kill intestinal parasites. The trees all walnuts put out a hormone called juglone that inhibits plant growth around them… not all plants can grow near them. They make astounding shade trees but the black walnut has a husk fly that can be gross (walnuts falling in water will show white maggots)… commercial walnut fields are sprayed but residential trees are often not so it’s possible to infest someone’s tree with the husk flies from black walnuts