black sooty mold and insects

[VickiC]

I just noticed this morn. that 4 of my orchids had a very small infestation of scale....maybe 2 or 3 scale....no more than 6 or so on all 4 plants combined. I also noticed that these 4 plants had black sooty mold (once again, not a large amt., but nevertheless some) The plants were all in approx. the same area....3 on mounts, 1 in a basket, near the end of one of my benches. If any area of the greenhouse gets less humidity and airflow than the others, it would be this area, although I think the entire greenhouse in general is sufficient in both from what I have read in past posts (2 large fans--1 under each bench, approx. 55-75% humidity in the summer, and much less in the winter, so I have to work harder then to control it). Also, the temp. is hot in the summer (approx. 90-95 degrees). I have sometimes read conflicting answers about various problems on the internet, so I would rather have your opinions and advice. Is there a connection between the mold and scale (insects, in general), humidity and/or airflow or was it just coincidental that I found both problems on all 4 plants? Once again, I would appreciate your help.
Vicki

[WhiteRabbit]

algae will turn black - might it be algae rather than mold?

[Gin]

Sometimes the sugary sap from buds can grow a sooty mold also some of the ant baits like Antrol and Revenge it is the sugar in it . With insects present it can be them causing it ..the residue they leave ..

[VickiC]

Hmm...well, it looked black and sooty...kinda fuzzy-like. I got lots of algae in S/H pots and on my greenhouse floor, and it didn't look like that. I'm far from a pro, though.

Originally Posted by WhiteRabbit

algae will turn black - might it be algae rather than mold?

[VickiC]

Hi Gin,
Ok...good to know about the sugary sap...thanks, but 3 of the plants affected were small and the other one was quite a bit larger....none have ever had buds. But, could it be ants themselves...not ant bait? I have ants often. I have found them in bottoms of pots, too....lots of em.
Vicki

Originally Posted by Gin

Sometimes the sugary sap from buds can grow a sooty mold also some of the ant baits like Antrol and Revenge it is the sugar in it . With insects present it can be them causing it ..the residue they leave ..

[Gin]

The ants feed on the sooty stuff it is probably sap from the plant tissue from bugs having a snack . Ants have been bad this year . I have read they farm pests move them around so they have a food supply .. I would spray the plants for scale they are the pits miss 1 egg and they are back .. I use a systemic like Bayer from Lowe's . Take no prisioners !

[VickiC]

Thank you, Gin!
I've already removed the scale, wiped off the sooty stuff with alcohol and sprayed with the dish drops, cinnamon, water and alcohol concoction. I'll spray again in a few days. When I do, would you recommend that I use the same thing I did today or the Bayer? Tomorrow I'll go on a mission to kill ants! ....and as you said, "take no prisoners!"
Thanks again,
Vicki

Originally Posted by Gin

The ants feed on the sooty stuff it is probably sap from the plant tissue from bugs having a snack . Ants have been bad this year . I have read they farm pests move them around so they have a food supply .. I would spray the plants for scale they are the pits miss 1 egg and they are back .. I use a systemic like Bayer from Lowe's . Take no prisioners !