Should I be worrying about these larch needles?

[Michigan Tree Murderer]

This Larix laricina gets morning sun until 1pm and watered well daily, & potted in 100% pumice, I haven't touched it since pinching the first flush about six weeks ago. I'm in MI so no heat wave like 80% of the US. Some of the needles have turned brown and died. I've treated it with a copper fungicide every month despite knowing the correct fungicide frequency. Is this something to be worried about?

Some look like this.


One branch is all brown, despite the new growth.


This side looks fine. And I do rotate the pot for the east sun.


I'm also summoning @Dav4 because he has sweet tree & is in MI.

 

[Dav4]

I've never had a larch so can't comment from experience. I do know they love sun so I'd suggest giving it more if possible just on principle. Also, when was the last time it was repotted and how well does the soil drain. They also love water so anything impeding water uptake at the roots could probably cause needle issues. Fwiw, the true MI larch guy is @mattspinniken, so I will try to summon him .

 

[mattspinniken]

Ha! I don't know if Im the true Larch guy in Michigan but I will comment.... Im 90% sure that your tree suffered some drought condition one or two days on an extra hot day. Let me guess, it is mostly at the top of the tree?

This has happened to me (usually on a pretty minor scale) many times. Its a sign to watch your watering and intense sun.

 

[WNC Bonsai]

I would never pot one in 100% pumice, you’re just asking for trouble. L. laricina often grow in bogs whoch means heavy orgaic soil and wet conditions, which pumice will not give you. Mine are in 50:50 mix of pumice and pine bark. The dead and dying leaves dried out and I would keep it out of direct afternoon sun until you can do a repot next spring. I have lost a couple to hot August days in full sun.

 

[Michigan Tree Murderer]

Ha! I don't know if Im the true Larch guy in Michigan but I will comment.... Im 90% sure that your tree suffered some drought condition one or two days on an extra hot day. Let me guess, it is mostly at the top of the tree?

This has happened to me (usually on a pretty minor scale) many times. Its a sign to watch your watering and intense sun.

Thanks that's reassuring. I'm mostly worried about fungus, and if it's just some drought damage I'm good with that. And yes it is mainly all on the top. I moved it to a spot that gets shade earlier than it was after posting this thread. Now it's getting morning sun till around noon. Thanks again I really appreciate the help and advice.

 

[Paradox]

I also think it might be a bit on the drier side especially if it got repotted this year. Newly potted trees tend to dry out faster than teees that have been in the pot for a while.

the all brown branch in the second picture still has buds that look OK though as does most of the rest of the tree so I would very worried yet. I'd just make sure that pot isn't drying out during the day and water it again if it looks like it is

 

[leatherback]

Does not look like fungal. This is what mine look like after heatstroke and/or dry roots.

WIth larch it is especially important to not let the pot get too hot.

 

[Michigan Tree Murderer]

I would never pot one in 100% pumice, you’re just asking for trouble. L. laricina often grow in bogs whoch means heavy orgaic soil and wet conditions, which pumice will not give you. Mine are in 50:50 mix of pumice and pine bark. The dead and dying leaves dried out and I would keep it out of direct afternoon sun until you can do a repot next spring. I have lost a couple to hot August days in full sun.

I went back and looked at the soil and there does seem to be some pine bark mixed in. Not 50% but maybe 35%. I didn't repot the tree this year but I bought it in April so it could have been repotted before I purchased it.

 

[Michigan Tree Murderer]

I also think it might be a bit on the drier side especially if it got repotted this year. Newly potted trees tend to dry out faster than teees that have been in the pot for a while.

the all brown branch in the second picture still has buds that look OK though as does most of the rest of the tree so I would very worried yet. I'd just make sure that pot isn't drying out during the day and water it again if it looks like it is

That's what I think happened. Will the needles that turned yellow//brown die off & come back? This is my first larch. I also have no idea if it's been repotted as I just got it in April.

 

[Michigan Tree Murderer]

Does not look like fungal. This is what mine look like after heatstroke and/or dry roots.

WIth larch it is especially important to not let the pot get too hot.

That's good to know. We haven't had a super hot summer like most of the world has, but it's summer so it does get hot, and it looks like we have some heat coming. It was 52F last Wednesday & Thursday morning.

 

[leatherback]

t looks like we have some heat coming

It is mostly about the pot sitting on a hot day in full sun & being dry. This is why you see [wet] cloth on pots in summer.

 

[Paradox]

That's what I think happened. Will the needles that turned yellow//brown die off & come back? This is my first larch. I also have no idea if it's been repotted as I just got it in April.

The brown needles will eventually fall off and regrow from buds next year. If the branch where all the needles are brown, stays alive, the buds on that branch will make new needles next year.

I've had one of my larches turn yellow from heat/drying out a bit and it recovered fine and grew the next year.

Remember larch are deciduous and lose their needles in the fall