Hello, Our magnolia tree has white spots all over its trunks and black on it's leaves. I was wondering how to treat it and hoping it is not fatal. Can anyone help?

It looks like it has sooty mold. Do you see any signs of scale or aphids? Are you able to add some closer pics? Is there a taller tree leaning over it?

Thank you so much for your reply!

Agree that the black mold is a sign of a sucking insect.
The white on the trunks is lichen and is nothing to worry about.

Thank you Horitica.The tree looks like it is dying this year. the leave and flowers are begining to bloom on some parts but there are lots of dead branches and they are covered in black. I wondering if a systemic Insect control will help or if i have to buy a fugicide. I fear I will lose the tree If I don't do something. Neem oil has not helped.

Believe it is scale.

https://entomology.ca.uky.edu/...

Looking at how much the tree has died back, I suspect more than just the bugs...
What do you know about your soil?
It really looks like possible root issues to me, as well.
I'd be thinking about propagating.
These Japanese magnolia trees are generally easily propagated by layering.

I don't know anything about propogating with layering. Is there a link or website you can refer me to?

Layering is easily searched.
https://content.ces.ncsu.edu/p...
https://www.rhs.org.uk/propaga...

I find that a lot of shrubs, trees, and vines grow roots when lower limbs have mulch cover them...

When I'm rooting a tree branch, I might place a pot of soil next to the tree and place a branch on top of the soil with a brick, rock or whatever to hold limb in place...

But... usually, I just hold the branch to the ground with soil, a coat hanger, one of those staples for holding down ground cover fabric, or mulch and a rock if necessary.

Very easy. Far easier than rooting cuttings.

Those are descriptions of ground layering, the easiest kind when it's possible. Just set it and forget it until the plant, your schedule, and the weather align.

There is also air layering, which takes a bit more effort but once you get the hang of it, a lot of individuals can be created much more quickly, on average, than with ground layering. I don't have the hang of it, can't relay any anecdotes, but can't claim to have tried beyond half-heartedly. So my lack of info to share is no reflection on the method.

But multiplying a plant that has scale, if your plant does, would almost surely just result in having 2 plants with scale instead of 1.

purpleinopp said:
But multiplying a plant that has scale, if your plant does, would almost surely just result in having 2 plants with scale instead of 1.

My advise was directed toward keeping the tree from dying due to whatever root issues are going on.
I think that a healthy plant would be able to fight off an insect issue... That doesn't look like a healthy plant.
Kill the bugs, and the tree still dies.

Could be.