Are these black spots on various species leaves fungal?

[birdmcfarland]

I’ve had orchids for 20+ years and very few problems but now I’m seeing these spots. Is this fungal?
Thank you
Melody

[estación seca]

Welcome to the Orchid Board.

That looks like bacterial. Go to the Web page of the St Augustine Orchid Society and look on the page for diseases.

[Shadeflower]

from what I have been reading in camille's guide the second picture looks like erwinia.

That should be cut away as it is a fast spreading infection.

I see signs of spider mite damage on the third picture.

Overall very common stress symptoms on weak plants.

Remove the leaf on the second picture.

Some might get plant treatment, like physan 20 to disinfect the growing environment.

But ultimately a stressed pant needs a good growing environment. If temperatures or light levels are not acceptable then the plants will grow more stressed and problems are more likely to occur.

So yes each plant has a problem and it is because they are in a weak state most likely so building up their defence needs to be the first step.

They are still salveagable so it was good to ask for advice.

If you need help figuring out what you can improve then ask away. Like I mentioned your light and temperatures are the most important.

What are you watering them with and are you using fertilizer? A small steady amount of fertilizer is needed to build up their strength.

Like K-sci pointed out recently I shouldn't assume you don't know how to care for them and don't get me wrong, I have these problems crop up from time to time also so to me pant nr 2 needs most attention but overall it is just a matter of treating for pests, feeding them right and keeping temps and light levels in the right ranges.

I'm sure others will have some further tips

[birdmcfarland]

Oh geez. Thanks so much for the help. I will respond fully tomorrow, short on time at the moment.

[K-Sci]

Originally Posted by estación seca

Welcome to the Orchid Board.

That looks...bacterial. Go to the Web page of the St Augustine Orchid Society and look on the page for diseases.

I agree, estación seca, that looks bacterial, and Shadeflower's diagnosis, erwinia, would agree. There are no good treatments for bacteria, once it is in the plant. The best course of action is usually to amputate the diseased areas, just as Shadeflower suggests.

There are translucent-looking areas spreading on some of the leaves. The translucent areas plus a bit more should be removed, in my opinion, to prevent the infection from getting into the bulbs.

That said, it isn't unusual for Stanhopea (for example) to get black spots similar to these on the leaves. When this occurs, it is often due to under-watering with water (or a pot) that has a high content of dissolved solids (such as hard water, softened water, or fertilizer). I'm wondering if that may be the underlying cause.

Diagnosing and treating diseases isn't my forte, so perhaps you or Shadeflower could comment further.

-Keith

[Shadeflower]

Originally Posted by K-Sci

Diagnosing and treating diseases isn't my forte, so perhaps you or Shadeflower could comment further.

-Keith

Nah, Keith, diagnosing a plant illness is like diagnosing a fracture on a person without an x-ray machine.

We can only take educated guesses. Sometimes people try to help that really have no clue and just come up with theories but as long as you have a bit of experience then an educated guess is as good as one can get without having a plant x-ray analyser to tell you.

I think you are exactly what this forum needs but at the same time it can cause a lot of people to disagree with you and then you might end up with angry private messages that the people helping have to unfortunately deal with.

I think a lot of people will chose not to comment when it comes to illnesses because it is hard to know the right answer..

[K-Sci]

Originally Posted by Shadeflower

I think you are exactly what this forum needs but at the same time it can cause a lot of people to disagree with you and then you might end up with angry private messages that the people helping have to unfortunately deal with.

Argue with a real expert and they'll tell you why you've got it wrong. Argue with a person only posturing as an expert and they'll lose their minds (e.g. send angry messages).

-Keith

[K-Sci]

This concerns me greatly. It and the surrounding area should be removed ASAP. This looks like a secondary infection.
-Keith

[WaterWitchin]

The black spots, I don't think erwinia. Looks like bacterial brown spot to me. The one picture K-Sci says he'd be most concerned about... the brownish mushy part of leaf looks like secondary infection, maybe erwinia. Erwinia travels fast, and I'd get that leaf cut off ASAP.

Using a bacterial spray treatment or bacterial/fungal treatment would likely be helpful. Or I've had good luck with bacterial brown spot cutting off the worst leaves, parts of leaves with just a bit of spot, or putting a cinnamon paste (bit of Elmer's glue mixed with cinnamon so it stays put) on the spot after spraying with rubbing alcohol. But that's just what I do.

My bacterial/fungal X-ray machine is in the shop for repairs, so know this is just an educated guess looking at a picture. And that educated guess has nothing to do with a degree in anything, other than a bunch of plant growing.

---------- Post added at 09:03 AM ---------- Previous post was at 08:54 AM ----------

PS Try not to splash water from plant to plant, and maybe up your air flow, if you haven't already done so.

[Shadeflower]

Originally Posted by Shadeflower

from what I have been reading in camille's guide the second picture looks like erwinia.

That should be cut away as it is a fast spreading infection.

Remove the leaf on the second picture.

I thought I had mentioned that already but glad there are two more agreeing.

Now to wonder if the OP will find the time to post a follow up