Black stuff on Green Giant

[chi gala]

I noticed some black goop-like looking stuff on my green giant and that a few leaves seem to be turning black in places. Otherwise, the tree looks healthy. Anyone know what it is and how I treat it?

Thanks in advance for all help!

 

[lone wolf]

@Raintree

 

[Raintree]

That's a good one, I've seen spray on fertilizers blacken Arbs. I've seen phomopsis fungus blacken Arbs. None of which looks like that.
I'm guessing it's something abiotic that was brushed or splattered on your plant. Have you tried to wipe it off? Is it isolated or is it all over the Arb?

 

[chi gala]

That's a good one, I've seen spray on fertilizers blacken Arbs. I've seen phomopsis fungus blacken Arbs. None of which looks like that.
I'm guessing it's something abiotic that was brushed or splattered on your plant. Have you tried to wipe it off? Is it isolated or is it all over the Arb?

Thanks for the reply.

I haven't tried to wipe it off. It appears to only be on a few of the lower branches at this point, or at least that's the only place I've currently spotted it. The affected branches aren't all next to each other.

Background: The tree was planted about 5 weeks ago. This is the first I've noticed the black on it. I've attached a couple pics of the tree. There are a few dead/brown branches here and there that I believe are from damage from the install. We do get a lot of deer (hence the neighbor's half-eaten emerald greens), but not sure how the black stuff would come from them. I haven't sprayed the tree with anything.

 

[Raintree]

Good sized plant, is it possible it was planted using equipment like a bobcat?
You could be looking at grease from the machine.

 

[chi gala]

Good sized plant, is it possible it was planted using equipment like a bobcat?
You could be looking at grease from the machine.

They did move it with a small bobcat type thing. I'll try to wipe it off today and see if that helps discern what it is. I've just been worried that it's something like black knot but for arborvitaes, but I can't seem to find anything like that when I search.

 

[chi gala]

Good sized plant, is it possible it was planted using equipment like a bobcat?
You could be looking at grease from the machine.

I was able to wipe off a lot of it. The leaves are still green under it. It doesn't smell like anything. I guess it could be some type of grease. A fungus wouldn't be able to be easily wiped away, right?

 

[Raintree]

Yes, fungus won't just wipe off, I think it's just grease from the equipment used to plant.

 

[chi gala]

Yes, fungus won't just wipe off, I think it's just grease from the equipment used to plant.

Ok, thanks for the help! Relieved it's not a fungus.

 

[lone wolf]

Yes, fungus won't just wipe off, I think it's just grease from the equipment used to plant.

Will fungus glow under a black light like mold?

 

[Raintree]

I couldn't tell you lone wolf, don't have any experience growing fungi. Have lots of experience eradicating it from trees and plants.

 

[sand sock]

You have a fungus called pine-apple rust. It jumps back and forth from species of tree. It's orange to black on pines and some sort of spot or deformity on apples. You can leave it alone or treat it with a fungicide or use dissolved ivory soap and spray it.

 

[Raintree]

Pine apple rust? Lol