AusBonsai

Hi all,
I've noticed these bumps on the branches and trunk of my j squamata for some time now,
recently, my area has had a lot of wet weather and it appears that these bumps are breaking with what appears to be roots as shown with the pictures.
So i'm wondering, are these actually roots or is it some disease?

I also see these on juniper branches but the trees do not suffer so not a disease. I think it may be some sort of callus like the tree is thinking about growing roots from those spots. I know that I do get aerial roots from my shimpaku when the lower branches are very protected and damp close to the ground.

thanks shibui,
i might try and wrap moist sphagnum moss around it and see if anything happens then

UPDATE:
roots have grown. Interesting that i have not ringbarked the branch at all and it still produced roots.
anyone know when to remove the layer?.

Good on your for documenting this!

I find it quite a fascinating little experiment you've conducted here.

Your in a bit of no-mans land in terms of removal - you could:

1. Likely remove now or preferably in a couple of weeks when the tree has fully slowed down for winter.
2. Wait until next spring when there will be more roots and an improved chance of survival.

There are pro's and con's of both the way I see it...

1. The tree might not have enough roots to support itself if removed in a few weeks.
2. This runs the risk of dry-out or rotting as I've often found layer environments hard to keep right in terms of wet/dry for extended periods of time...

The 3rd option (which may not be possible) is to drop the layer with sphagnum and all into a pot with potting mix to grow at leisure - this way it will be easier to look after.
You can remove it next spring and slowly remove the sphagnum over time.

Layers will survive with remarkably few roots. Getting roots started seems to be the hardest part, once started they can grow very quickly when needed. It is not entirely clear how much tree these small roots will need to support if it is removed now but this time of year is a good one to do so. Tree has reduced needs for water, etc but still warm enough for continued root growth to catch up with the foliage if needed.

This runs the risk of dry-out or rotting as I've often found layer environments hard to keep right in terms of wet/dry for extended periods of time...

I have also experienced this problem but this example is quite different. It has not been ringbarked (I assume?) so water and nutrients can freely travel through both parts. Also, as it is in a pot it will get watered frequently, unlike layers on garden plants. As long as the sphagnum is watered and fed regularly those roots should continue to grow until spring which is the optimum time to separate.

Sounds like I'm having a bet each way here but I'm pretty confident removal either now or spring would work here. Depends how lucky/clever/confident JL42 feels?????

I checked one of my raft style shimpaku today. Despite no bark removal and the trunk behind nearly 1cm above the potting mix there are now roots growing down from the trunk into the pot below. I have occasionally seen shimpaku roots grow several cm through air to get into the soil - almost as good as figs