Japanese maple issue - disease? Insects?

[AndrewAustralia]

Hi All,

I have a few maples - one maple forest, one by itself and another green maple on its own. The green maple is great but the red maples (forest and one alone) seem to be suffering lately...

See attached some photos. The new leaves generally go limp and droop. A bunch of leaves have heaps of pest damage on new and old leaves.

Some leaves are also spotted which you can see in the first photo.

The last two photos are of the red maple on its own. The leaves have begun to turn a darker red colour on the edges which is not evident in the forest.

I have been watering less recently but still fertilise regularly. It is worth noting, not all the maple forest trees have been impacted as much as the others.

Any ideas on what's going on and how I repair it?












Sent from my SM-G950F using Tapatalk

[terryb]

Not sure about the colouring but the third photo looks like caterpillar damage. They have been particularly abundant at my place this year and I estimate I removed about 30 last week from my japanese maples alone.

[AndrewAustralia]

Hey there,

Yes I figured some caterpillar damage but I check daily for them and can't see any! Do they know when I get home from work? I really don't know.

Sent from my SM-G950F using Tapatalk

[Watto]

Give your tree a spray with something like rose spray - insecticide and fungicide - just to be on the safe side.

[AndrewAustralia]

Thanks. Something like this?

Anyone have any opinions on dropping leaves?

Sent from my SM-G950F using Tapatalk

[TimS]

I’ve got a big old Japanese Maple and had a few issues with the leaves, though not identical to yours. Mine seems to have been a combination between the soil being too wet and insect activity. The Rose spray or Rose Shield is solid stuff (wear a mask) but it will nuke any insects/ fungus attacking your plant. Probably worth checking to see how damp your soil is if it’s been a few years since last repotting as this caused the most significant problems for my tree

[treeman]

viewtopic.php?f=129&t=23250&p=234060&hi ... ps#p234060

[AndrewAustralia]

I only planted it around April this year but I think I may be watering too much.

Not sure what you are suggesting with your thread link? That there is powdery mildew forming?

Sent from my SM-G950F using Tapatalk

[Raging Bull]

If you have insect damage and can never find the little buggers chewing your trees go out at night with a torch on a regular basis, some of them work night shift.

[MJL]

Ok - I am no expert but I seem to be going OK growing Japanese maples.

I reckon your photo's show a number of issues.

One being insect damage - Confidor does the insect job for me and for maintenance (to keep 'em away) I spray something like nature soap and/or pest oil every other month or so.

I used to get powdery mildew on some younger seedlings. Essentially my issue was limited airflow where I was originally growing them; now they sit in dappled shade with good airflow - watering daily but airflow is better and have not seen any powdery mildew lately.

I hope this helps.

PS - I am not gonna speak on Treeman's behalf but in relation to your question about the thread he listed - I think Treeman was simply pointing out a link to a historical thread that was similar and contained helpful advice.

[AndrewAustralia]

Thanks mate for the help

Anyone have thoughts on eco neem as an alternative Confidor or Rose Spray? Rather than buying yet another chemical...

My trees get good air flow. They are outside and get shade and sun throughout the day. Very open area really.

Sent from my SM-G950F using Tapatalk

[treeman]

Not sure what you are suggesting with your thread link? That there is powdery mildew forming?

No, that the third picture clearly shows thrips damage.

[AndrewAustralia]

Thanks mate. Can't seem to find Confidor at Bunnings or the other products in the older post. E
Will eco neem do the trick, or Rose Spray? I did find white oil insecticide in my garage. Thoughts?

My only other query is - do I just pinch off the new growth that has been damaged? I worry my maple will stop sprouting new growth....?

Sent from my SM-G950F using Tapatalk

[shibui]

Bunnings have discontinued all Imacloprid products including Confidor because of adverse publicity related to bee deaths. You should still be able to find these at other more reputable nurseries.
White oil can be damaging in some circumstances, especially hot weather, so read all the warnings before you use it. I have not used Neem so cannot comment on what it does. Rose spray is a combination insecticide and fungicide and should be safe for your maple but may or may not solve the problem.
Each product only treats certain pests and diseases so random sprays may not work unless they target the specific problem. It is difficult to choose accurately if you are not sure of the problem. You may eventually hit the correct product with random applications but you may not be able to work out which was the correct one for next time.
Treeman has referred to mites as a possible cause. Try a product that treats mites first and see what happens.
I have seen similar issues on my trees but the problem disappears later in summer so spraying and getting good new growth may just be a coincidence because the problem went away by itself.
You can safely pinch off damaged maple leaves and shoots. They resprout very readily. Plenty of feed and water will help and new growth sometimes grows even stronger than initial spring growth. No need to worry about pinching JM.

[Beano]

Mitre10 has confidor where we live. I worry about bees to but I think if they aren’t attracted to your trees by flowers then harm possibility is limited as long as you aren’t spraying it on them or getting overspray everywhere on a windy day.

Don’t know about neem, but I don’t find pest oil useful for many of my trees issues. Unlike a tree in the ground with more nutrient access and capability of strong growth, a tree in a small pot may not cope with pests and diseases as well or for as long as one in the ground, so I feel less guilty about using chemicals on mine if it means they get the chance to continue living. I’d love an organic world but I don’t think it’s worth risking the bonsai for it. As soon as you figure out what is going on get some spray. In the mean time, I’ve found rose spray pretty useful for my suffering deciduous which haven’t leafed out properly after winter.