Hello, In this maple tree, there was a smallish dead twig in the center of the tree, about where three other branches fork. Somehow that dead twig fell off and left a hole in the middle. I am now concerned that fungus, or bacteria will develop in there and water accumulate when it rains what would be your advice to ensure the wound doesn't make the tree weak and diseased? Or how to protect it (wax, tape, wound sealer?)? Thank you
With à brush, you can put a little Bordeaux mix in it and around, thats all. -Just a little powder and water in a spoon.
I think it definitely needs filling with something, as if water were to collect in there and freeze it would not be a good look come the spring. I would be interested to see what horticultural experts would recommend, there is bound to be a professional product that is used in this situation. From an amateur perspective, I would first clean the hole out of any soft/rotting woody material and then fill it with some type of non-toxic filler or putty that becomes totally inert once set. Sugru would be perfect for this, which, if you don't have experience of this product, is kind of like playdoh when you open the sachet but sets to a non-toxic rubber that is resistant to heat and cold. Otherwise a food safe building sealant such as OB1 or CT1 would be my next choice. If you have anything to hand already that is non-toxic and sets to an inert weather resistant substance then I would use that rather than buy something. If you can clean all the soft/rotting material out and it leaves a channel for any water to drain away then the Bordeaux mix suggestion from @opusoculi would be the way to go, but if a hole is left where water can collect then it really needs filling with something IMO.
I hope I'm wrong but, to me, it looks like disease is already developing all around the branch on the right. You can see the stub of another small branch on the far right. Besides that, knowing that even two branches that fork can lead to future problems for a tree, here you have three. Going out on a limb and depending on how large your tree may be, I'd be thinking of removing all three branches below where they join and then wait for a new bud to produce a single branch to carry on growth in that direction.
DO NOTHING, everything looks quite healthy. Seriously, nothing looks bad to me. I am not an expert, but I have seen numerous branches looking like that, and it is just the sign for bark expanding, nothing to worry about.
I hope @Margot is wrong too, the problem does not seem that bad yet, but may obviously get worse over winter. I get the impression this is a fairly small tree and a large portion would be lost if it had to be pruned below the wound - this would be a last resort for me if the infection was seen to be spreading from the initial wound site.
To me looks like two options here, as @Nik said, do nothing. Or seeing that the tree is so young, cut off both branches to the right and let it grow as next spring it will flush with new growth and by summer you will start shaping the limbs to the look you would like to create. Japanese maples overall are so resilient and rebound so quickly. That cavity will heal itself imo.
Thank you everyone! I am adding here photos so that you can see what it looks like better That's a relatively young tree - Acer Shirawasanum Jordan - that I was gifted in spring. It's now about 80cm tall, and this year the tallest branches have grown about 30cm. I would think that removing two branches (as been mentioned above) would be indeed a good idea, as there are four of them at about the same junction. Cutting below the junction would cut almost the whole tree, so I don't think I'll cut that low. In the following photos, I've named the branches Branch 1 to 4. (Branch 2 and 4 have small wounds, as highlighted) Branch 2 and Branch 3 could be the ones to go as they also go inside the tree and close to the others, that would enable the hole to have a small channel to have the water drain and not stagnate in the hole. so I would guess that a plan of action could be: 1. Cut branches 2 & 3 (and probably the two small shoots that have just come out) 2. Make a small channel from hole to outside 3. sulfate copper
