Acer palmatum 'Bi hoo'

Mine is by far the last maple in my collection to leaf out. Mine is finally starting to push leaves when most of my other trees have been fully leafed out 4-5 weeks ago. Amazing bark in the winter. And not much blacking on the tips.

 

The tree has great winter bark but as for spring???

 

I'm still waiting for mine to leaf out. It's had these mini partially unfurled leaves for a really long time. Out of +/- 75 JM's, I have four that are worrisome. This one, my Ukigumo, my Azuma Murasaki, and my new Aureum. Knock on wood, the rest are plump and sassy. And, so far, none of the others look in imminent danger - they're just scraggly looking.

But my Bi hoo has the dreaded blackened stem tips. I keep waiting for it to either get better or die, but it's like it's in stasis. I've given them all soil soup periodically so now all I can do is wait.

 

Finally mine leafed out. Nothing special in the spring but the winter bark is unlike anything else.

 

It died.

 

here is the color on the 10th of august, it looks pretty good now.

I have added a photo of the tree taken 4 oct 11

 

Here's my (rather sad) little baby Bihou :( First year graft, so no surprise that it looks so pathetic after the extreme heat we've had all summer (95+ nearly every day since early June, no exageration), but I am worried about the blackened tips. I've taken it to both our local extension office and spoken with someone from their master gardening program, as well as taken it to one of the better nurseries in town that is a little more knowledgeable on JM's, and both seem quite certain that the die-back is simply from the heat. I tend to believe them, but as this is my first year owning JM's, I'd like input from those more experienced.

If it is simply die-back from the heat, do I cut it off now/later in fall, or leave it on until spring (will protect the rest of the branch from further die-back?)? If it isn't die-back, what do I do? I've also attached a picture of my little 'Squitty' that's in the same boat...

 

The thing about this forum I've noticed is that unless a reply appears within a day or so,your post can be easily missed.Hopefully by replying,someone with more knowledge,and especially of fungicides can chip in.
Firstly,well done for getting such tiny plants through that hostile weather.Undoubtably they will have suffered a bit and had some die back.The tips have blackened,usually caused by bacterias called 'pseudomonas',entering the damaged tips.It seems most coloured bark types seem to get this as par for the course and I think most people snip them back and hope they don't get reinfected(though still possible if conditions remain hostile)
If you look back on this thread you will see 'Tim Nichol's' post regarding the blackening on 'Bi Hoo'.He says that 'Alternaria' has been diagnosed as the culprit for the blackening on stems that appear away from the tips.I must admit,I had this as your tree does,and panicked as the darkness travelled down the branch,so removed the branch,but 'alternaria' is an extremely common fungus with many varients affecting most living plants,so there is probably a fungicide that could be used.
So perhaps a bit of research is needed to resource this,or hopefully someone may recommend a product....I'd also be interested to know.It'll do no harm spraying with whatever fungicide you use now (though may be inaffective)...good luck!

 

I think first year grafts can be a little tricky, and it's not unusual to see some dieback. I put this down to the healing graft preventing flow from the roots to the leaves and vice versa. Without sufficient leafing out the roots have a hard time, and the whole thing can be a vicious circle. So I wouldn't put the blackening down to pseudomonas which for me make spots anyway.

At this point your Bi hoo looks like it has good buds, so the trick will be to get it through the winter. If it leafs out again now that's probably OK too. Hopefully the 2 buds below where it's blackened through will remain viable, to cut the top off now would endanger them further I would guess.

My little 1st year Bi hoo is doing very well with lots of good foliage, I'm pleased to say. But the first winter is always critical.

Good luck,

-E

 

My first Bihou, posted above, ended up dying, so I purchased another last fall. Came through the winter fine, and until it nearly got drowned out (I left it out during a 5 day spell of rain in early March, didn't dry out for 2 weeks), then got either pseudomonas or a fungus (treated twice with phyton 27), it was doing ok. After drying out, and treatment, it seemed to recover decently, and while I have not noticed any dieback, the leaves don't look all that appealing - though, they aren't wilty, so I'm taking that as a good sign.

I'm sure the crisping on the leaf edges is from either too much sun - it was getting several hours of midday sun until a couple of days ago - or the darned KS wind, or both, but is the spotting just residual from what it went through earlier this spring, or a sign of something else? Any feedback would be appreciated!! Though not a stand-out, it is a pretty little thing (I love the bark color), and I'd hate to lose it.

 

This cultivar is notorious for spotted leaves. You will never get rid of it...

 

All I have to say about Bi hoo is that it seems to have the possiblity of issues. I lost a good size branch on mine this last year. This will probably be my last year for keeping the tree in the garden. I do love the winter bark but the rest of the year is just ok. i will just need to figure out a good winter bark tree, maybe japanese sunrise.

 

It's not terribly pretty, but if this is a common occurrence for the tree, then I won't worry. The winter bark color, followed by the spring leaf out, is enough for me to want to keep the tree, at least for the time being. Thanks for the replies!

 

This year with our dry hot september the upper leaves are burning a bit. I love the color of the bark but I await a new duplicate which has a better growing habit. I find it requies more pruning than many trees to keep a good shape.

 

I just bought a small Bi-hoo today with a small Sangokaku. Lots of blackening on both, so I got a third off on the prices. The leaves are similar on both, so it most definitely is a relative. I have removed all of the blackened stems down to a healthy bud. Lets see what happens :)

 

I got one in summer 2013 and it has had only very minor twig blackening and dieback in the last two winters despite a lack of special treatment. I really expected it to fare worse than this.

 

Yes I've noticed Bi hoo has finally started to appear in garden centres this year.There'll probably be many disappointed customers as it can suffer when young but improves with age.I suspect it's bark is it's weakness as it has a soft plastic look about it on less mature branches but it does colour up no-matter the sun exposure and mine still has yellow right down to the rootstock.

 

So would you say that bihou is not a very hardy plant? I really love the upright look of it (when bottom is more trimmed) and the winter bark color. But from what I read on this forum, seems like it suffers from a lot of issues. I am also confused with the size as some websites say 12-15ft tall and wide, and some say 7-10ft tall and wide. That's a huge difference in terms of mature size. Thanks!

 

I went to a garden center to buy a new pair of branch-cutters.

I saw a 'Bi Hoo'. Thought "No, no, no, you mustn't!" Went looking around and had "you shouldn't" in mind. Finally went back to the maples section, said to myself "Perhaps..." and bought it, with a dark blue pot for the contrast.

I know a lot of people here have had issues with this cultivar, but since I will keep it in a pot, the risks are limited (I hope).

 

Found a lovely one at an excellent price locally, so happy to have this one in my collection again.

 

Mine is doing well. It's facing west, shaded by the trees around until mid-afternoon and is one of the first to display its autumn colours. Next to it, a 'Lemon Lime Lace' which is still green:

 

Dawes Arboretum has it listed as
Acer palmatum 'Bi hō'
Synonym: Acer palmatum 'Bihou'
"Comments: This introduction of a deciduous tree from Masayoshi Yano features bright golden-yellow stems most apparent in winter. The spring foliage is flushed with salmon-pink becoming greenish yellow in summer. It is a relatively compact specimen but can grow 8-10' tall in 10 years. Would make a great specimen for winter visual impact."
Acer palmatum 'Bi hō' - Bi hō Japanese maple | The Dawes Arboretum

 

I am adding a photo of my Bi-hoo and to comment on how it fares in my garden.
Firstly I love the colour of this one in all seasons. I have it planted next to Sangu Kaku so that the contrast of yellow and red branches stands out and gives a bright Winter interest.
Secondly, the die back, yes it has this problem regularly, but with constant monitoring it does do OK.
If anyone was going to buy this cultivar they should be told about this before buying, otherwise it can come as a shock and you think you have a problem tree.
The only drawback with trimming the dead tips regularly, it will, stunt the growth somewhat.
But IMO it is a price worth paying for the lovely colours. I have no regrets in adding it to my collection.
Here is a photo of mine in Spring 2020, showing the lovely leaf colour that also lasts through the Summer.
D

 

The maples forum is not all about lovely trees, sometimes it is important to post how a cultivar fares through the seasons. Good or bad.
Bi- hoo is a beautiful tree but it has it's problems. It is very sensitive to sun and wind causing scorching of the leaves, this you can see in my photos along with the Bi-hoo die back.
I hope people will take this as a warning about this tree, if you are considering buying one.

 

August 15th 2020, this is how my Bi-hoo has coped through the heatwave, not pretty I agree, but so important to show here.
Definitely a buyer beware maple IMO. This is one tree that gets shorter every year in my collection.