Leaf burning on Hornbeam

[proninyaroslav]

Hi everyone. This is the second year I have been faced with a strange disease on my Hornbeam. The first time was at the end of summer 2023. This year it appeared earlier, in May, mainly on the leaves of the apex. In 2023, this combination of fungicides helped me: difenoconazole + flutriafol + epoxiconazole + cyproconazole . This year I treated in early spring with only epoxiconazole + cyproconazole. Later, when brown edges appeared, I decided to treat with Strobi based on kresoxim-methyl. I didn’t change the substrate, maybe it’s worth changing it next year to prevent the disease spores from spreading? By the way, it's not in direct sun, so it's not a sunburn.

 

[Gabler]

Are you sure it's a fungus? What do the roots look like? What kind of soil are you using? How and how often do you water?

 

[Bonsai Nut]

That doesn't look like fungus to me.

It looks like leaf burn - which doesn't always have to be caused by the sun. It can be caused by high salt content in your water, high mineral content in your soil, or over-fertilization - particularly with chemical fertilizers.

 

[proninyaroslav]

What do the roots look like? What kind of soil are you using? How and how often do you water?

I repotted it last year. Substrate: diatomaceous earth + perlite + pine bark. Water when the top layer dries a bit. Maybe dried it out one spring and watered it later. There is no direct sun, only early in the morning, the rest of the time it's partial shade.

high mineral content in your soil, or over-fertilization - particularly with chemical fertilizers.

Fertilize once a week like other trees. My mix drains well and I water it generously (but let the soil dry out a bit between waterings). Everyone reacts well to this, except for the Hornbeam. Last year this happened in July, and in August-September I was able to stop further burning.

 

[Dav4]

It's a root issue, imo. As mentioned above, it's likely either too much water or fertilizer.

 

[proninyaroslav]

It's a root issue, imo. As mentioned above, it's likely either too much water or fertilizer.

I don't think it has too much water, it dried out pretty quickly during the spring flush. I'll try to reduce the frequency of fertilization by half.

 

[proninyaroslav]

Drying of the leaves continues to progress. Could this be a sign of anthracnose on the hornbeams or root problems?

 

[R0b]

Looking at the green mossy spot on the soil, when you repotted did you remove any of the field/nursery soil?

 

[proninyaroslav]

Looking at the green mossy spot on the soil, when you repotted did you remove any of the field/nursery soil?

I thinned out some of the moss; there was much more of it last fall. It originally grew on the trunk and scattered its spores . I haven't replanted it since last spring. I left a decent amount of roots and didn't trim them. Before that, it grew for 2-3 years with another owner. This is yamadori, and it hasn't the original soil for a long time. I planted it in the same mixture as my other trees. Last year I also got burned leaves, but this happened towards the end of summer. This year it began 2-3 weeks after leafing out, mainly on the upper branches. Why I suspected anthracnose was because it was on the dogwood last year, and this year it appeared on two other trees. Although these leaf edges do not look typical for anthracnose, maybe I'm wrong and these are root problems or something else

 

[Deep Sea Diver]

Hmm…

Seen this damage often in the fall on horn beans as the leaves start abcission, not in the spring.

Sure looks like the leaves are drying out fast. Decidedly doesn’t look like a fungus at this time.

The mix described can dry out plenty fast depending upon the proportions of each. Also the amount of sunlight could exacerbate the situation.

Whatever it is the le@ves are not staying hydrated. So this could a a drying out issue, or too much fertilizer causing a root issue. If roots, any root issue could be intensified by multiple fungicide additives.

Another cause could be too much water… but that is more remote.

One issue is problems begin to compound at some point. For example weakened trees are prone to secondary issues.

A couple basic bits of information might help.

How much sun/shade and time of day of each?

Proportions of media mix.

Timing/ amount of watering?

pH and carbonate levels in the water.

Type, amount of fertilization

Best
DSD sends

 

[R0b]

I thinned out some of the moss; there was much more of it last fall. It originally grew on the trunk and scattered its spores . I haven't replanted it since last spring. I left a decent amount of roots and didn't trim them. Before that, it grew for 2-3 years with another owner. This is yamadori, and it hasn't the original soil for a long time. I planted it in the same mixture as my other trees. Last year I also got burned leaves, but this happened towards the end of summer. This year it began 2-3 weeks after leafing out, mainly on the upper branches. Why I suspected anthracnose was because it was on the dogwood last year, and this year it appeared on two other trees. Although these leaf edges do not look typical for anthracnose, maybe I'm wrong and these are root problems or something else

What kind of soil is along the base of the tree and how long has it been there?

 

[proninyaroslav]

What kind of soil is along the base of the tree and how long has it been there?

I haven't replanted it since spring 2023. A mixture of diatomite, perlite, pine bark.

A couple basic bits of information might help.

Mostly morning sun until midday. After this, the sun is shaded by trees, and after lunch it goes behind the other side of the house.

I use a mixture of diatomaceous earth, perlite and pine bark. Approx. 50% / 30% / 15-20%.

Watering when the top layer dries visually and tactilely depends on the weather and wind. Now that it gets hot about once every 2 days, it doesn't drink too quickly since it doesn't have active growth and a lot of leaves and roots. I water all the trees generously to wash away excess salt and saturate the soil with water.

The water is about 250 ppm, 1-2 years ago it was much harder. Soil pH is about 6-6.5, water pH is about 7.

Previously I used 18-18-18 fertilizer + microelements, but now I switched to a more balanced 19-6-20 (I read Leo's articles, thanks to him). I also add a small handful of chicken manure/Tamahi.
I apply fertilizer once a week, the dosage is slightly higher than that indicated by the manufacturer (you could call it "superfeeding", but I don't add 5-10 times more as is usually done in superfeeding). The next day I wash it off with a clean water. This amount of fertilizer didn't affect the health of the other trees, I didn't get leaves burned or anything like that. So far I haven't fertilized Hornbeam, as soon as I noticed the situation is getting worse (about 1.5-2 weeks ago), I don't feed sick trees.

 

[proninyaroslav]

@Deep Sea Diver
What do you think this could be?

 

[Deep Sea Diver]

Always fall back on Occam’s Razor in these situations. Basically the simplest answer is usually the best. In horticulture things are a bit more complicated, but the principle works well if a systematic

The water is very hard, which leads to nutrient lockout, yet the pH is low, so this ought to be ok

The tree shows definite signs of not getting enough water.

Four things cause this (besides a couple esoteric things that don’t believe apply. These are much water, too little water, too much sun and root issues.

Reports state the watering is sufficient… is this based upon the other trees in your collection growth.

That leaves roots. Usually one looks at how roots can be damaged. Basically, mechanical, biological and chemical.

No repots for a couple years rules out mechanical.

Biological rarely occurs alone… usually something creates an unhealthy environment first… root damage, poor media, overwatering… this is not happening according to reports.

That leaves root damage by chemical means. The most frequent cause of root damage by chemical means is over fertilizing. This basically causes the root cells to give up water and dehydrate with each over fertilization. However the roots become more easy to damage with each succeeding application. The repeated insults doesn’t allow healing. At this point the roots become susceptible to biological damage.

…. And that’s where we end up with my conclusion. The fertilization schedule is one time a week using a superfeeding schedule…or deliberate overfertilization. That’s, imho is too much fertilizer. Walter Pall the advocate of superfeeding wrote to me explaining that it isn’t for all trees, one must know and understand the needs of each species.

[imho the fertilizer schedule is too frequent for any tree. Once a week and overfeeding each application is very aggressive and it’s doubtful in our practice if this would be effective as there isn’t anything to gain by doing so. and a lot to lose. The added nutrients debilitate the rhizosphere, leaving the tree solely dependent upon added salts and minerals…. and leave the roots at risk of damage. ]

So what to do? Not sure about the tree as it looks from the last set of images show possible biological damage too.

If this was my tree would stop fertilization. Water sparingly. Put in open shade to reduce the transpiration load. Don’t use fungicide as doubt it will help and could hurt at this point. Cross fingers and see what happens.

Hornbeams are naturally pretty strong trees, so rely on the tree to do what it does best.

Hope this helps and that the tree makes pulls out!

Best
DSD sends

 

[proninyaroslav]

@Deep Sea Diver
Thank you! Can the hornbeam produce a second flush of growth if these damaged leaves eventually fall off? Or will the result of the healing be clear only next spring?
P.S: I applied fungicides a couple of times because at first I thought it was a fungus. And besides, I did this preventively, since some trees this year had spots on the leaves due to wet and cold May. Maybe this also affected the final result and, as a consequence, greater drying of the leaves.

 

[Deep Sea Diver]

Thank you!

…. You are most welcome. Hope things work out for the tree. In any event there has been some good response and dialog on BN

Can the hornbeam produce a second flush of growth if these damaged leaves eventually fall off? Or will the result of the healing be clear only next spring?

….If the roots can recover the tree should respond this year It may limp along for awhile.

P.S: I applied fungicides a couple of times because at first I thought it was a fungus. And besides, I did this preventively, since some trees this year had spots on the leaves due to wet and cold May.

….Jan - May are always wet and cold here. Leaf spots and bugs will always happen

…..Trees out of storage are all chocked up on one side. In any case preventive sprays and/or drenches should be kept to the least innocuous, copper, zinc, hydrogen peroxide , soap etc.

…..If one knows there is an actual issue or history of a specific issue, use a product specifically effective to the issue…. Read the product SDS and wear safety gear appropriate and store all remaining products accordingly.

Maybe this also affected the final result and, as a consequence, greater drying of the leaves.

….Hard to tell for sure, yet somewhat doubt as damage should have been more widespread.

Cheers
DSD sends

 

[Maros]

@Deep Sea Diver
Thank you! Can the hornbeam produce a second flush of growth if these damaged leaves eventually fall off? Or will the result of the healing be clear only next spring?
P.S: I applied fungicides a couple of times because at first I thought it was a fungus. And besides, I did this preventively, since some trees this year had spots on the leaves due to wet and cold May. Maybe this also affected the final result and, as a consequence, greater drying of the leaves.

If you do partial defoliation now, this time of year healthy hornbeam will produce a new flush of growth in a few weeks. Not sure about sick tree though. But removing tips of the shoots and the majority or all damaged leaves should not hurt IMHO.

 

[Betula1]

Sorry to here about your problems with your Hornbeam. Have you looked at the condition of the roots?
It sounds like you are over-fertilising the tree and have damaged the roots ,leading to leaf scorch symptoms seen in the photos. Repeated doses of various fungicide cocktails really isnt necessary and may well be making things worse.
I suggest you flush the medium thoroughly with clean rainwater to remove fertiliser salt build up , then let it drain and recover until the roots regenerate, dont feed again and water sparingly and wait for new healthy growth to emerge.
Here in UK the native Hornbeam Carpinus betulus is frequently grown as a hedge and can happily be clipped during the growing season ,after which it normally back-buds and grows secondary shoots and leaves.
It is normally a very hardy species which thrives in light shade and isnt difficult to grow and has few health issues.

 

[proninyaroslav]

Have you looked at the condition of the roots?

I can do this only next year

 

[August44]

I can do this only next year

Not sure I agree with that. I have lightly popped trees out of their pots by holding onto the trunk and taping on the edge of the pot in several places which loosens tree in pot and out it comes. If it comes out as a ball with soil attached to the roots, all the better. If all or most of the soil falls away from the roots, just be prepared to mist roots with water, be quick to look at the roots and notice anything suspicious, and immediately repot without removing or messing with the roots. I can't remember loosing a tree using this process. I would have someone helping that can take pictures and help you with the process. Just my opinion of course.