The confined space you mention, what is doing the confining? If you have your tree planted in a hole in a solid concrete area, your trees roots will be suffering from a lack of oxygen beyond the four foot hole. Most of a trees roots are close to the surface due to the air available there. My Arbutus Marina is 15 years old and 30 feet high and wide. It has never been fertilized and only watered the first year. These are a truly wonderful tree and I hope you can save yours. Al

I live in SSZ 17 and I can't imagine watering my 'Marina' arbutus -- ever. They get the water they need from Nov. to April rainfall. During the rest of the year, they want to be dry. That's what makes them such a good tree for California.

I have a similar problem with my Arbutus. I planted the tree 6-7 years ago and it looked great. But recently it started to lose leaves, it does not look that green anymore and branches are bare. It looks like it is dying.
Any recommendation?

GadiS the Arbutus is best grown in a Mediterranean climate with soil that drains well. Your post gives no hint of where you are or how you are growing it. Al

Hello, we are in North CA in the bay area. I think it is zone #15. The soil in my back yard is not that great as there is a hard layer about 10-15" below the ground level. However, I tried to dig a fairly decent hole when I planed the tree 6-7 years ago. Probably 30" wide and 20" deep. Many leaves looks brown/yellowish right now.
Question is how can I try to save this tree? Thanks for your help.

Hello, we are in North CA in the bay area. I think it is zone #15. The soil in my back yard is not that great as there is a hard layer about 10-15" below the ground level. However, I tried to dig a fairly decent hole when I planed the tree 6-7 years ago. Probably 30" wide and 20" deep. Many leaves looks brown/yellowish right now.
Question is how can I try to save this tree? Thanks for your help.

Well GadiS you are in native Arbutus territory. I am in your Sunset zone and have six acres with many native Arbutus as well as my planted Marina. If you could post a picture it might help. Your tree may be suffering from a fungus such as Phytophthora ramorum better known as Sudden Oak Death. It affects the Arbutus as well as the Oaks, but does not usually kill them, just makes them sick. If you have such a problem you would need to provide samples to your Extension service. Call your local county office for more information. This is a worse case scenario and probably not your problem. Al

If you have Oak root fungus you may find out sooner than later. We lost our healthy 5 year old Marina (6 inch trunk diameter) to this. It started at the tips with die back and all the leaves died off within a month or 2. Exposing the crown and roots we could detect a white fungus under the bark. In our case this is not the first time a tree has died from this fungus in our yard. Poor drainage is a factor as well as infected root systems from older trees (In our case the trees have been removed but the roots remain). If your tree dies - try to dig out as much of the old root system as possible.

Chad

We had two15 foot arbutus marinas planted, 48 inch box, one year ago. This year, many days the trees look wilted and leaves yellowing. I have slow, deep watered 3 times a week and they will begin to look better. The recent heat wave affected them again and while watering I noticed their bark is all crackly ready to peel. Underneath, the trunk is yellow/green spotted instead of the beautiful red. Is this normal? See picture. Thanks!

Yes, that's normal for them. As the tree grows the old bark splits and peels, the new bark will turn red in time. Your attention has probably cause a growth spurt, a good thing.
At one year, your trees are probably not fully established, so they will need the extra water, however three times a week is too much for them I think. Try to limit it to only once a week.

We had hardly any rain this last winter, so they are probably taking longer than usual to establish themselves.

As the weather cools cut that down to about every other week, and by fall probably only once a month. But after a year more you will not need to water them as often. Probably only 3 times a summer or so then, at the most.

This post was edited by BarbJP on Wed, Jun 11, 14 at 23:37

I agree with barbjp. You are using your tree as a street tree and installing it from 48 inch box. A large tree installed in a confined area, will need considerable time to establish. It is much easier on the tree to establish from a much smaller size. Al

I would be concerned. As stated in an above post, Arbutus Marina are susceptible to phytophthora root rot. Overwatering, especially in heavy soils, can play a factor. I lost two potted ones this way; the soil mix was too heavy and the watering too frequent by a caretaker while we were on vacation. The plant will often wilt, especially when heat stressed. The leaves may turn yellow or reddish. Early on, it may not affect all of the branches. Mine actually appeared to recover for a while, but would relapse with stress. Larger plants may take longer to succumb. I cannot say if your trees have this disease, but it takes more than a bit of heat to make a healthy Arbutus wilt.

Edit to clarify; should more correctly be: The infected plant will often wilt, especially when heat stressed.

This post was edited by Gyr_Falcon on Thu, Jun 12, 14 at 15:13

Thank you all. Of course, I like BarbJP's answer better! Gyr_Falcon - our trees were planted in a very rich topsoil so I wonder if your concern for disease does not fit this case. I am not deep watering regularly, only when they look wilted and they seem to perk up then. I just got alarmed when I saw the color of the trunk under the peeling bark. This is my first time having Arbutus trees.
Thanks again!

Truthfully, Gyr_Falcon has a really good point.

You do have to be very careful not to over-water these trees, they can be very susceptible to root rot in soil that's damp and warm. So do err on the side of dryer soil.

Rich topsoil isn't their native soil so be even more careful. If the "topsoil" was sandy loam, it would probably be OK, however if it was rich compost, be extremely careful to not over-water.
Really it's more, let it dry out before you water again. Soil that's damp all the time, has less air in it, which plants need just as much as water, some more so. And warm, damp soil can invite the fungus that causes root rot.

In nature, these often grow on hillsides, in summer fog belt areas. So they can get some water in summer, but it would only be what drips off their leaves from the evening and morning fog. They like the soil to be on the dryer side during the heat of the day.

In cool winter weather they're fine with damp soil as the soil is also cool, in warm summer soil, you have to be careful to not over-water. Good luck.

I find this post very interesting and thank everyone for their contribution.
I've seen an unusually high amount of Arbutus Marina death and decline in the past year. At least a half dozen.
At first I thought it was over watering and then came across three that were planted in very fast draining sandy soil.
I hav not seen any signs of bark or subsurface mold or fungus.
The local Extention service here in Marin County is not taking samples so I will be submitting to an independent lab if the cllient(s) agree to the lab cost.
I have been seeing this in Santa Cruz and Marin Counties.

Candace, it is difficult to diagnose from a few forum words. Your tree may still just be getting established--15' trees are large specimens, and installers always have to expect some to just not make the transition into the field. The flaking bark is not a problem--it looks exactly like that on my healthy arbutus. Many trees with this type of interesting bark pattern, such as eucalyptus and sycamores, have periods during the year they tend to flake bark heavily. With mature eucs and sycamores it often comes off in 7-10' pieces and makes a noticeable mess. Arbutus bark flaking is much more discrete.
What alarmed me was you saying that it wilts often. Remember, this root system in the hot confines of the box container was supporting that 15' tree at the nursery. In the ground, after a year, the tree should be less stressed than when it was in the box, not showing more stress. Frequently deep watered while in very rich topsoil is not good for this tree. I'm sorry. I really hope they pull through and thrive. These are great trees.

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deviant-deziner, another disease to which this tree is susceptible is Botryosphaeria canker and dieback. This fungus tends to take advantage of weakened trees. The outer crown foliage will often look healthy, but the smaller inner-canopy branches begin to shrivel and die. If memory serves, the older, lower leaves on the tree go next. I don't know what symptoms your local trees are exhibiting. Please share the lab results if tests are done.

Update on my posting 6 months ago. The trees are doing better as far as the leaves and fruit go, but I am concerned by the chalky white trunks and open "wounds". These trunks were beautiful when first planted 1 1/2 years ago. What would cause them to split and turn gray/white like this?

This is the problem with Arbutus marina. Prune off the affected branches using a disinfected tool between cuts so you don't speed it. Prune if a few inches back from any cankers so wthey do not overwinter.

https://extension.psu.edu/botryosphaeria-canker-in-the-home-garden

I have really had it with arbutus marina trees near the beach in SF. We lost four out of six. I would call them fussy trees. We live basically on sand and did not water the last four after a year. They go great guns for four years and then get sickly in the crown and split up the side. I see rotten ones on the street all over the neighborhood (outer Richmond to Sea Cliff). I noticed that the non-rotten ones tend to be planted much higher than the ground level on a little mound, so I did that with our last four, but two of them already rotted. Probably they have infected a remaining one, which is already weak in the crown. Maybe our whole neighborhood has some strain of phytophthora. No more for me. It is a big effort and lots of time for nothing.