help to identify larch needle problem

crust

Omono
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The bad needles are a bit floppy and have a dulling cast from a distance but up close have light orangish striations. The orangish striations do not scrape off--it seems integral with the needle. Earlier I suspected spider mites and then thought this was post spider mite damage however it is increasing on one tree. There is currently no sign of spider mites via the paper test but earlier there was some evidence so I sprayed with a miticide and for 3 weeks I have seen no evidence of the mites--this all may be unrelated though. New grow is coming weakly and I have let it extend. It is pale green but does not seem stricken. I looked up larch needle blight and larch needle cast but nothing fits exactly. Has anyone seen this? At this point, I will be spraying with mancozeb fungicide maybe alternating with another.
 
The bad needles are a bit floppy and have a dulling cast from a distance but up close have light orangish striations. The orangish striations do not scrape off--it seems integral with the needle. Earlier I suspected spider mites and then thought this was post spider mite damage however it is increasing on one tree. There is currently no sign of spider mites via the paper test but earlier there was some evidence so I sprayed with a miticide and for 3 weeks I have seen no evidence of the mites--this all may be unrelated though. New grow is coming weakly and I have let it extend. It is pale green but does not seem stricken. I looked up larch needle blight and larch needle cast but nothing fits exactly. Has anyone seen this? At this point, I will be spraying with mancozeb fungicide maybe alternating with another.
larch needles.jpg
 
Bump --does anybody know what this is???
 
Bump --does anybody know what this is???
I don't.
But I've seen that color before on some of mine.
Lost them all.
I would first isolate it so whatever it is ,it can't spread.
I don't know if it does for sure but I wouldn't take any chances.
Good luck Dave.
Hopefully you get it figured out soon.
Your trees are much nicer than mine and I would hate it if you lost some.
 
If I has to guess, I would say some kind of fungus or a root problem.
 
Probably red spider mites. They infest a tree in the billions and if you do not stop them they can kill the tree. If it's not mites it has to be some other disease probably untreatable.
 
How established is the tree? I had some collected this year that started like this and turned into what looked like needle cast when googled. It was an isolated incident and limited to only a couple shoots off a branch. I did not treat them and they died back, new growth is juicy and did not effect any other areas. This leads me to believe the not enough roots suggestion, however the rest of the tree is super vigorous and havent lost any other branches. Seems like if it diddnt have enough roots to support it,would have dropped more than the couple shoots. Either way I hope it fades and its not cancerous to the rest of the tree
 
I also have this on my larch!
Yikes--find out what it is and tell me!
My understanding is the damaged needles do not really recover and one must tough out the growing season then next spring spray with fungicide (really not sure which, some say daconil, manzate, mancozeb) as the buds unfurl the again in 2 weeks and again in 2 weeks. This is the typical rec for foliage diseases.
 
Yikes--find out what it is and tell me!
My understanding is the damaged needles do not really recover and one must tough out the growing season then next spring spray with fungicide.
You can't spray right now? I'm assuming youd be okay but im no expert
 
Larch are rarely susceptible to many problems like bugs and fungi. How hot has it been?
The word "Rarely" does not mean never. Talk to Nick Lentz, he is the first to tell you about the almost endemic infestation of bores in collected Larch. You should test for Spider mites, that's pretty simple and painless and un-arbitrary like any fungus diagnosis would be. How much do you water, what kind of soil the list of possible causes and sources are open.
 
I'd say a fungus of some sort, either on the leaves, or from the roots, but like many diseases, the environment (climate, soil, light,...) can trigger an attack.

Something similar happened to one of mine, I lost the top and the following sping, when repotting, I saw that the roots on one side were almost all rotten.

The second time it happened on another one, I removed the tree from the pot without touching the roots, and put it in a larger one, filling the empty space (under and around the roots with 100% pozzolane 6-12 mm (1/4 - 1/2 an inch). It got better in a short time, probably because there was more oxygen for the roots and the drainage was better.

On maples that had fungal pbs, I used a diluted solution of hydrogen peroxyde (about 20%, but I think a lower volume is OK, like 10%): it kills the germs and bad bacteriae, but preserves the good ones.

Maybe it's worth trying: the risks are very, very limited I think.
 
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