
22 November 2023
You’ll inform a tree through its nuts: Black walnut
Black walnut bushes (Julgans nigra) are commonplace within the Pittsburgh space. Their nuts are all the time able to consume in time for the vacations.
In September the fruit used to be nonetheless at the bushes whilst we looked for fall warblers a number of the leaves.

By means of the tip of October the fruit had fallen and began to seem bruised. Ultimately the husks became black.

However maximum black walnuts aren’t deserted that lengthy. Squirrels collect them for iciness meals and consume a couple of alongside the best way.

Squirrels know that they’ve to open the shell on each side to get the entire nut meat.

The beef does no longer pop out simply! It generally breaks into small items at the means out and is rarely the easiest form of grocery retailer walnuts.

Those we purchase within the grocery retailer which can be grown in California are English walnuts (Juglans regia) which might no longer be conceivable with out the life-giving participation of black walnut bushes (Julgans nigra).

Non-native English walnuts are prone to root sicknesses in California so walnut farmers plant local black walnut bushes to begin the orchard. When the black walnuts are a yr outdated with sturdy roots and energetic base they’re chopped off and an English walnut shoot is grafted to the stump.
All of the bushes within the orchard under display the broader stump base (highlighted in yellow) that ends on the graft level. Above the graft English walnuts produce their very own scrumptious nuts which might be harvested when they fall through sweeping and vacuuming from the bottom. FLORY harvesting apparatus is pictured under.

Black walnut bushes will also be recognized in iciness as a naked tree status on my own with twigs that experience trade (no longer reverse) small buds above massive leaf scars.


Black walnut bushes stand on my own as a result of …
Like different walnuts, the roots, inside bark, nut husks, and leaves [of Julgans nigra] include a unhazardous chemical referred to as hydrojuglone; when uncovered to air or soil compounds it’s oxidized into juglone this is biologically energetic and acts as a breathing inhibitor to a couple vegetation. Juglone is poorly soluble in water and does no longer transfer a long way within the soil and can keep maximum concentrated within the soil without delay underneath the tree.
Signs of juglone poisoning come with foliar yellowing and wilting. Quite a few vegetation are in particular delicate. Apples, tomatoes, pines, and birch are poisoned through juglone, and as a precaution, must no longer be planted in proximity to a black walnut.
(credit are within the captions)