Nostoc bacteria or slime mold

[NeedlesAndLeaves]

Hey all,

The black sludge I found, am I correct that it’s Nostoc Bacteria or slime mold?
I have this on the soil of some of my conifers.
I know it has to do with moisture. Note: I only water when the soil is dry (for conifers).

I only have this on some of my pines, junipers, hinoki and a spruce. I have several and not al of them are affected by it (standing side by side).

All of them are in the same soil (akadama/pumice/lava/kiryu) 1:1:1:1.
Some which are in a pondbasket are starting to show as well. But all are absolutely free draining.
Note again: I only water when the soil gets dry. And it’s the sunniest spot in the yard.

I am using organic fertilizer. In baskets, monthly alternated with a dose directly on the soil. Using osmocote and fish mix as well.

The year has been a bit wet and with autumn started it will be wetter even more.

I scrape this stuff off from time to time. But is there another solution to deal with this?
I read it is not harmfull, is that correct?
Getting them in my shed for every drop of rain does not feel like a natural thing to do.

Those affected trees are on the same benchlevel which is the sunniest (conifer)spot.
My other (broadleaf) trees don’t have this problem, they are not on the same bench though.

Any advise would be appreciated

Grz Jasper

 

[NeedlesAndLeaves]

Anybody?

 

[penumbra]

It looks more like algae than slime mold to me.

 

[Wires_Guy_wires]

Yeah, I'd say those are dead algae. They tend to turn black when they die in wet and colder conditions.
The slime molds we have here are orange, yellow or red-ish in color.

 

[NeedlesAndLeaves]

Oké tnx for replying gents
I use quality free draining soil. Overwatering therefore feels like it is not directly the problem. Do you think the direct contact of organic fertilizer to the soil will cause or stimulate this?
I will use it only in baskets for a while.

Is there a good way to deal with this algue? It is mostly near the trunk. (It is black to the eye but on your finger it is more green). If possible without losing the moss on the edges ?

@Wires_Guy_wires you don’t have this on some your soil in our weather?

 

[Wires_Guy_wires]

Yes, I have this too. When it rains for a good decent period, and my fall nutrient application is fading out, algae bloom and then die when the last bit of nutrients flush out and they have no food left.
It then becomes fungal food, which is great! Because my mosses don't grow unless there's fungal colonization of the soil.
It's free carbon, man!
But it can form a hard cake layer on top of the soil, which will prevent it from breathing well and it can prevent good water penetration. So keep an eye on it, and if you see the plants struggle, it's time to scrape that layer off.

 

[RaginCajun]

You use organic fertilizer? I’ve noticed I get this on trees where organic fertilizers are applied directly to the soil. I perform “Soji” on trees in the fall with this algae on it and scrub the trunk or roots with a soft toothbrush and soapy water. Dawn dish soap will do, won’t hurt the tree one bit. While you’re at it go ahead and clean the trunks and branches. Makes the trees prettier.

 

[NeedlesAndLeaves]

You use organic fertilizer? I’ve noticed I get this on trees where organic fertilizers are applied directly to the soil. I perform “Soji” on trees in the fall with this algae on it and scrub the trunk or roots with a soft toothbrush and soapy water. Dawn dish soap will do, won’t hurt the tree one bit. While you’re at it go ahead and clean the trunks and branches. Makes the trees prettier.

Organics yes. Tnx for the advies

 

[rockm]

As Cajun said, that mold is from the organic cakes left on the soil. It's pretty common if you don't put the cakes in something before placing them on the soil. There are fertilizers baskets and some people use tea bags. You can buy pack of a couple hundred empty fillable tea bags for a few bucks. Works well as water runs through the bag and fertilizer too, but the silt is left inside, so you don't get the mess.

 

[Glaucus]

With moisture and organic fertilizer, stuff is going to grow. And with light, it could be algae as well. This is the 'benefit' of organic fertilizer.

For me, blackbirds will pick a hole in the teabags if you were to use those. You need to guy the completely enclosed baskets. And then check every week if they weren't pulled and thrown off.

 

[NeedlesAndLeaves]

I use the fertilizer in baskets one month and the next dose I put directly on the soil in between and so on. Leaving each dose two months like this,
so all is optimally used.
Will use only baskets from now to see the difference.

 

[RaginCajun]

I use the fertilizer in baskets one month and the next dose I put directly on the soil in between and so on. Leaving each dose two months like this,
so all is optimally used.
Will use only baskets from now to see the difference.

I did forget to mention, I switched to using solid organic fertilizers in teabags.. now, no issues with algae.