Brown leaves and stunted growth on Coast Live Oaks

[TrueSandwich]

I've had these oaks for a bit and earlier this year they had a bit of a hiccup in growing. They restarted and now it has started to get stunted again. I thought it was lack of fertilizer or insufficient/ overwatering, but best I can tell it is a pest or fungal infection. Anybody have any experience with this?

 

[Wulfskaar]

This has happened to some of mine as well.

My first thought is overwatering because some of the ones that had this issue were growing in potting soil and may have been too wet.

However, there are also little webs, so it could be some kind of bug. I'd love to know too.

 

[yenling83]

Issues like this will generally improve as your overall horticultural care increases. This could be from factors relating to light requirements, obtaining correct balance of water and oxygen, soil, water quality, nutrition, etc. These areas we can all continue to improve in and is part of the life long journey that is Bonsai. With Coast live oak, you want them in full sun in a well draining medium. They may need shade during temp spikes and really hot days. Often Coast Live oak roots with make your soil become like concrete, not allowing water and oxygen into the root system. I rotate spraying different fungicide and spray every 1.5 months. They can also get spider mites and are subject to other pest issues-which you can spray for as well. Just based off the pics, it would be really challenging to determine the specific issues. Long term it's possible you could just struggle with Coast live oak because the area you live/grow them in. Have you tried Valley Oak? Valley oak appreciate the heat and grow more inland compared to Coast Live oak. I would think Coast Live oak should grow well in Paso, but I could be wrong. Do you water the foliage? That could possibly increase susceptibility to fungal issues. I also find my live oaks can become quite weak after a repot that involves cutting alot of roots-but they bounce back after the first year. Best of luck with them!

 

[MrBonsai19]

A pest issue should be fairly reasonable to identify maybe not the exact pest but at least presence. You can put yellow sticky trips on it and also try the white paper spider mite test.

I had some issues with a coast live oak and got good feedback here

M

Thread 'Help with a recently yellowing Coast Live Oak'

Dec 8, 2024

This is a look at the tree when I bought it in two months ago:



It looked about the same for a month or so, however in the past two weeks the leaves have started yellowing (from the tip of the leaf back toward the interior of the leaf) :



I live in Oakland, California and was told the tree had been repotted in Spring of this year. We recently had a week-straight of rain, so I am worried it might be over-watering related, but I was also under the impression that a quality Akadama/Pumice/Lava mix would be hard to over-water.

I would love any advice about

1 -...

• MrBonsai19
• Replies: 17
• Forum: Other Deciduous

• 

I used a variety of treatments although in the end it was not clear to me exactly what turned things around. May just be very close watching and correct horticultural practice. As @yenling83 suggested. My tree is doing better now and I’m sure the proactive fungicide and pesticide treatments didn’t hurt.

 

[TrueSandwich]

Issues like this will generally improve as your overall horticultural care increases. This could be from factors relating to light requirements, obtaining correct balance of water and oxygen, soil, water quality, nutrition, etc. These areas we can all continue to improve in and is part of the life long journey that is Bonsai. With Coast live oak, you want them in full sun in a well draining medium. They may need shade during temp spikes and really hot days. Often Coast Live oak roots with make your soil become like concrete, not allowing water and oxygen into the root system. I rotate spraying different fungicide and spray every 1.5 months. They can also get spider mites and are subject to other pest issues-which you can spray for as well. Just based off the pics, it would be really challenging to determine the specific issues. Long term it's possible you could just struggle with Coast live oak because the area you live/grow them in. Have you tried Valley Oak? Valley oak appreciate the heat and grow more inland compared to Coast Live oak. I would think Coast Live oak should grow well in Paso, but I could be wrong. Do you water the foliage? That could possibly increase susceptibility to fungal issues. I also find my live oaks can become quite weak after a repot that involves cutting alot of roots-but they bounce back after the first year. Best of luck with them!

Thank you! There are some Coast Live Oaks (CLO) near my property, and they are thriving, but maybe they will struggle here as bonsai. I have a large Valley Oak on my property as well and I plan on harvesting acorns to grow for bonsai. I haven't seen any good Valley Oak material for sale, only CLO. I have 2 other CLOs and they are doing well, if not thriving, but I am still learning my new area. I regularly spray my weaker trees with insecticidal soap and/or neem oil which seems to have potentially helped as 1 is doing better than it was a couple months ago. I have an automatic watering system set up that I am trying to tune for a trip I am taking in a few months, so the leaves are getting misted every other day. I will get some fungicide and will keep up on the soap and Neem Oil to see if that all works.

 

[BrianBay9]

Here's a resource that can help. Field Guide to Insects and Diseases of California Oaks. Unfortunately there are lots of insects and diseases of California oaks.

For some reason the "link" below doesn't link. But it does work if you copy and paste it in.

chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://oaks.cnr.berkeley.edu/wp-content/uploads/2019/02/Field-Guide-to-Insects-and-Diseases.pdf

 

[yenling83]

Thank you! There are some Coast Live Oaks (CLO) near my property, and they are thriving, but maybe they will struggle here as bonsai. I have a large Valley Oak on my property as well and I plan on harvesting acorns to grow for bonsai. I haven't seen any good Valley Oak material for sale, only CLO. I have 2 other CLOs and they are doing well, if not thriving, but I am still learning my new area. I regularly spray my weaker trees with insecticidal soap and/or neem oil which seems to have potentially helped as 1 is doing better than it was a couple months ago. I have an automatic watering system set up that I am trying to tune for a trip I am taking in a few months, so the leaves are getting misted every other day. I will get some fungicide and will keep up on the soap and Neem Oil to see if that all works.

Eric Shrader has grown the best Valley Oak i've seen from Seed many years back. But yes, not too many of them in Bonsai and it's such a great species visually speaking. I have heard putting them in a Bonsai pot, they can be challenging from a horticultural perspective-but if they can grow anywhere in the US, i'd imagine Paso is a great spot for them if you can water them often enough and possibly protect when it get's really hot. My teacher Peter Tea keeps all his oaks in full sun year round, but he's watering up to 4+ times per day with some of them on the hottest days. I think all oaks in containers don't love water on their foliage and it makes them more susceptible to fungal issues. You might try setting up your system so it doesn't hit the foliage. Also, a couple good general fungicides are Daconile and Clearys 3336.

Hope you can collect some Oak trunks, I think that's a great way to find material! Growing from Acorn is also fantastic, I'd suggest experimenting with acorn seedling cuttings to get radial roots to create nice nebari. I've found it really challenging to get good nebari without doing so, likely because they want to send a deep tap root as young plants. Cheers!

 

[Wulfskaar]

Eric Shrader has grown the best Valley Oak i've seen from Seed many years back. But yes, not too many of them in Bonsai and it's such a great species visually speaking. I have heard putting them in a Bonsai pot, they can be challenging from a horticultural perspective-but if they can grow anywhere in the US, i'd imagine Paso is a great spot for them if you can water them often enough and possibly protect when it get's really hot. My teacher Peter Tea keeps all his oaks in full sun year round, but he's watering up to 4+ times per day with some of them on the hottest days. I think all oaks in containers don't love water on their foliage and it makes them more susceptible to fungal issues. You might try setting up your system so it doesn't hit the foliage. Also, a couple good general fungicides are Daconile and Clearys 3336.

Hope you can collect some Oak trunks, I think that's a great way to find material! Growing from Acorn is also fantastic, I'd suggest experimenting with acorn seedling cuttings to get radial roots to create nice nebari. I've found it really challenging to get good nebari without doing so, likely because they want to send a deep tap root as young plants. Cheers!

I have one 3 year old Valley Oak I grew from acorn. The leaves are beautiful and soft, especially compared to coast live oak. But... they just grow so dang slowly! Only one flush of growth in spring, while coast live oaks grow from January until late summer.

Development time is going to be much, much longer for my valley oak than my coast live oaks.

 

[BrianBay9]

I've never met anyone who has successfully collected a substantial valley oak trunk. I have a few, from nursery stock or acorns, and enjoy working with them. But collected valley oak? Haven't seen one.

 

[yenling83]

I have one 3 year old Valley Oak I grew from acorn. The leaves are beautiful and soft, especially compared to coast live oak. But... they just grow so dang slowly! Only one flush of growth in spring, while coast live oaks grow from January until late summer.

Development time is going to be much, much longer for my valley oak than my coast live oaks.

Very true they do grow so slow. It's fun to see Eric Schrader's Valley Oak from Acorn, but they took a long time!

 

[yenling83]

I've never met anyone who has successfully collected a substantial valley oak trunk. I have a few, from nursery stock or acorns, and enjoy working with them. But collected valley oak? Haven't seen one.

I'm glad you brought that interesting point up. I've seen a few that made me think they were Yamadori, including this tree below(stock photo, not mine), one in Andrew Robson of Rakuyo's collection and one from John Thompson. But, I don't know if they are actually collected or not. I'm curious, what have you heard or learned about collecting them? Do they not do well after collection? Or is it possibly hard to collect fine roots as they have large tap roots? When it comes to Oaks, I've only collected Coast Live oak.

 

[BrianBay9]

I'm glad you brought that interesting point up. I've seen a few that made me think they were Yamadori, including this tree below(stock photo, not mine), one in Andrew Robson of Rakuyo's collection and one from John Thompson. But, I don't know if they are actually collected or not. I'm curious, what have you heard or learned about collecting them? Do they not do well after collection? Or is it possibly hard to collect fine roots as they have large tap roots? When it comes to Oaks, I've only collected Coast Live oak.

I've not had an opportunity to try collect a decent valley oak trunk, so I know pretty much nothing. But if you watch how they grow from acorn they (like many Cali oaks) spend most of their energy early on pushing the roots. By the time they've spent a few years in a nursery can they have most of their mass in large tap roots. I suspect it would be rare to find a yamadori candidate that has feeder roots anywhere near the trunk.