For the second year necrosis on young pecan seedlings!

[hereistay]

Hi there,
I'm from Italy and asked you some questions about pecan cultivation in the last year.
Now, I have a new question for you!
I have some pecan seedlings born about a month ago.
During the first day I noticed some black spots on them and I thought it could be scab (maybe infected nuts) so I treated them once with Tebuconazole and a second time with mancozeb (it is used yet in Italy).
I have a third light treatment and after 2 days some plants started to show black vein spots and day by day leaves started to turn brown and dry.
Last year I had the same problem and my seedlings died one by one but, as I remember,7 I didn't gave any treatment.
Someone told me it could be excess of water.
Last week I put them in a tall homemade pot and I noticed that the bad ones had a spiralized taproot.
According to you what's the problem and what can I do?
I put them for the first month in the shadow and now have them where they receive about 3-4 hours of early morning sun.
I don't know how to expose young pecan seedlings, can you help me about it?
Thank you!


Cheers from Italy!

[!potatoes!]

First pic looks like the start of sunburn more than anything...the other pics less so. Is there a reason why you didn't have them in direct sun to start with? I have a feeling that all of these issues could be avoided by planting direct where you want them. Tap root will go straight down, used to full sun from the beginning, etc...

[hereistay]

There is not a reason but ai knew that it's not a good idea to put little plants under direct sunlight.

[!potatoes!]

I'm sorry, but that's not true. Direct-seeding many things (nut trees included) in direct sun works great - they start their lives already accustomed to full sun, and don't need to be hardened off. Works in pots or the ground (some rodent protection needed frequently in either case).