Issues with excess UV from light reflection?

[Triloba Tracker]

I've had issues with leaves of Asimina triloba (pawpaw) developing sunburn in the late season (last few weeks), potentially precipitated by very minor leaf yellowing.

These are on grafted trees that have been in the ground since April 2018 and have been in full sun since then.

Typically grafted trees are not planted with shade protection, though I have decided at least one year of shade helps root establishment.

All of this is to say, these trees "should" not be having problems with sunburn on the leaves.

One thing i have wondered about is reflecting sunlight off my bleached-out wood-chip mulch. The chips are rather pale from sun bleaching and to just stand out there is almost like being on a Florida panhandle beach - the light reflection from the sand is intense and makes you squint.

Does this make sense?

If so, I had the crazy idea to seek a free/cheap and NATURAL way to DYE the woodchips darker. I was thinking a "tea" of black walnut (native tree) or some other plant that would produce a dark stain, essentially.
Any ideas for this? Black Walnut is probably the best option...anyone who's handled those knows they stain something awful.

Asimina is supposedly immune to juglone and grows under Black Walnuts in the wild, so i am not concerned there.

[SeaWalnut]

It also grows on sandy soil on river beds ,wich is light in color.
Sprinkling somme charcoal over the mulch might work.
Charcoal not lighted off course  and not ash ,because that washes away while the charcoal can last for houndreds of years.
The char,because it contains a little ash on it,its slightly alkaline at first ,but you can wash it with somme water ( preferably in the process of making the char ).
You make a fire from twigs and at the end when( when theres no flame) only the red coals remain,you estinguish those with water and you just made yourself somme charcoal.

[Triloba Tracker]

Yeah I think I’m probably a little nuts with my theory of reflection but maybe not.

However, after researching and seeing how easy it is to make a potent dye with black walnuts, I think I HAVE to try it LOL

[SeaWalnut]

Be carefull not to poison the trees.They are juglone tolerant but that doesnt mean they like juglone or that they are not affected by it.
I planted my pawpaws as far as i could from any walnut .
Do a small test first to see if it works.

[Triloba Tracker]

Good point. And I don’t know how reliable the juglone/pawpaw information is.

I would use a tank sprayer to just apply to the surface mulch so little to no due solution would reach the soil. Except for rain and decomposition later.

[Pokeweed]

I spray my pawpaws with kaolin clay to give them a break from sunburn. Usually I do it several times in the summer, but got lazy this year and I have a lot of ugly leaves. D

[Triloba Tracker]

I spray my pawpaws with kaolin clay to give them a break from sunburn. Usually I do it several times in the summer, but got lazy this year and I have a lot of ugly leaves. D

ah-ha yes! I have read about that. What product do you use or what is your source? Forum member recommended Surround to me but it doesn't seem easy or economical to obtain......

[Pokeweed]

I bought surround from an ag supplier in Arizona. Arbico organics, and yes it was expensive. It also makes it harder for grasshoppers to eat your foliage, which was another reason I was using it.I have since heard that craft stores carry kaolin clay for something. Try one of those. D