Coast live oak weed issue

Hello Mirai
Just got a nice shohin sized oak from a nursery and the foliage took a turn for the worst the. Drainage seemed fine. Which I always turn to for health issues. So I did a repot to see what’s going on and I had about 45 weed/ seed things on one side of the tree. I imagine this was sapping up some resources. But maybe it’s fungal in nature 1st oak. Maybe someone can help identify seed/weed. As well if leaf change of color. Also I tried not to disturb roots to much but it was infested with these seed I hope I didn’t kill it by trying to save it. Thoughts did I kill her or him or did I save strong opinions make strong bonsai. Than you for any thoughts or comments.

I have had a few oaks over the year’s, mostly native live oak. They do not like root work, and I mean none whatsoever. Typically they self defoliate, sometimes they yellow/brown immediately, sometimes the process takes weeks, eventually all the leaves are shed. At this point it’s important to keep them a little on the dry side to prevent root rot in the container. Most of the time my trees rebounded and pushed some new growth by late fall. I definitely lost a few to what I would consider minor root work.

A side note

I had a single specimen take 2 years before it pushed growth again. I had given up on it, pulled it out of the container and placed it in a burn pile. While sitting there neglected for 2-3 weeks it came to life and back into a container container it went.

To summarize, careful and appropriate watering is going to be essential. The rest is time.

Tips for oaks

I currently do my oak repotting in late summer before fall. The trees respond better, for me this is also when I collect as well.

When I repot oak, treat them like pine.

I do not prune at all during growing season after spring cleaning. This builds stronger roots.

Never bare root oak species, same as pine. Both are very reliant upon fungal networks (mycorrhizae).

I will leave them in container for 4-5 years at a time.

I keep them in a dry mix and usually water them 1-2× per day during the summer, full sun in Texas.

They like slightly acid soil, neutral is fine as well.

I’ve used pumice/lava/haydite/turface 1:1:1:1
pumice/lava/haydite/turface/pine bark 1:1:1:1:1
pumice/lava/haydite/akadama 1:1:1:1
Pumice/lava/haydite 1:1:1

Mycorrhizal growth is better in pine bark mixes and in mixes with akadama. I use 1/8, 1/4, 3/8" particles, no 1/16th for any tree in my garden.

The growth of the canopy wasn’t or hasn’t been notably different in any of mixes when it comes to the components used.

The size of the aggregate definitely makes a huge difference. Larger particle size associated with more robust growth, not necessarily larger internodes and leaves.

Internodes affected greatest by fertilizer timing, strength and application (liquid vs pellets). I use organic only.

Oh yeah… the weeds, I just pull them as they sprout. I don’t work roots to remove them, too much damage with too little reward.

Weed removal is part of everyday bonsai maintenance. They get deposited in the container in numerous ways. Best to deal with them as you see them.

Bonsai on! I’m sure your tree will recover. Good luck!


Some great information by @ndavila80 that I plan apply as I move some oaks from seedling to prebonsai. I am wondering if what @Giordano is seeing are oak root galls rather than weeds. They seem to be much larger than most weed seed.

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It’s probably a bit of both, could even be some acorns as well. The live oak in my area will drop an abundance of acorns, literally thousands at a time usually once a year and on rare occasion twice. Water availability and overall temperature seems to influence the size, quantity and number of times they form and drop seeds.

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So this was the finished repot and I am seriously thinking of getting a heat bed to help root growth. Would this be ok. I’d only use it when I’m hope to make sure it won’t dry out. Also what do you think of this micro positioning. It’s in the front yard gets morning sun and afternoon sun. Under an orange tree. I think maybe a little more sun would be good after recovery after the recovery of the repot.

Yeah if I have time I’ll count how many there are. I don’t think acorns. But heavily infested unfortunately.

Partial shade as you described will be fine and I would try to eventually get it into full sun. A heat bed would/could help stimulate some root growth especially if you are going to experience more cold weather for a prolonged amount of time.

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Yeah if I have time I’ll count how many there are. I don’t think acorns. But heavily infested unfortunately.@Marty
Thank you @ndavila80
We will see Southern California weather has been extremely up and down. Nothing very cold though.
And I will put it in full sun when I have the time to watch it.

IF those were planted in there by Squirrels there would be major root disturbance/damage:face_with_symbols_over_mouth:and likely your health problem is solved. Maybe need to keep screen over the surface of your pot(s)?

@WLKeugene I would if I had squirrels by me. I repotted because it’s nursery stock.

Hmm. Just an insight I had that seemed to fit the situation well.

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To me these look like small bulbs, possibly grape hyacinth or something similar.
One bulb probably fell into the potting mix and multiplied over the years.
In general I would not hesitate to bare root a live oak like this to make sure all of the bulbs are gone, however, since the health of the tree is not optimal there may be reason to be more conservative. I realize you have already re-potted this tree.
It seems clear that these multiply so a follow up repot next year might be warranted to see if they are still present.
Other than sapping up resources I doubt they would be harmful, but in a small bonsai container with limited resources that could be a problem.


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Yeah, look like bulbs to me too

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They are oxalis bulbs, a vigorous and hard to eradicate weed. Remove when possible or they will always be there reproducing and sprouting.

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Hey update the repot has been pretty successful. Not to much die back, as well as some née growth. Thank you everyone.
Also I have not gotten any more weed growth. Thank you for the information on this particular weed.

Also you may notice a different pot. A day after I posted these pictures my golden doodle knocked over the oak tree. Fortunately I had an stone monkey pot that I could repot in. It didn’t fit half as well but I made a moss covering to support the root system, as the roots slightly go over the edge of the pot.

If you see stuff coming up in ypur pot that looks like clover and has yellow flowers those things in your soil are oxallis. Its really hard to eradicate from the ground so dont just dump them with the dirt. Remove as many as possible

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Yeah I think I got them all out and the tree is really making a decent push of new foliage. I don’t think I will do any wire or pruning for a year. To know if it’s fully recovered.

I’m glad to see the oak get new leaves but, I continue to have the leaves die back. Any advice will help. It is particularly shaded and gets watered pretty similar to all my trees which are all much healthier.
I am thinking I’m probably not letting the tree dry out enough. Any opinions are helpful.

I would concur with the not letting it dry enough. These are trees that are adapted to dry conditions.

I repotted a bunch of seedlings with quite a bit of soft fleshy growth this spring (things got ahead of me). I had to cut back the tap root and any really long roots to get them going in the right direction. Most them them wilted very badly and looked like they would lose all of the new growth. However, after about a week in semi shade most of them have perked back up. I don’t expect a lot more top growth this year since I anticipate they will put their energy into new roots, but I could be mistaken.

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