Suspicious dark leaf spots on several orchids.

[BrassavolaStars]

Hello All,

While bringing my orchids into the greenhouse for the fall (probably too early as unfortunately, it is still getting into the 90s outside), I noticed that several of my plants have dark spots on the leaves.

I think that the spots developed on the patio during the late summer but I cannot be sure as some may have had spots when I bought them.

The spots seem to be affecting primarily a Zygopetalum and Oncidiums (a Trichopilia). This is the reason the spots did not concern me originally because both of these genera are known for hideous spotted foliage (especially zygos)

Recently, I have noticed spotting on an Aeranthes, a Dendrobium kingianum, and a Coelogyne. the Aeranthes is especially worrying as the spots are on the new leaf.

The spots on the Trichopilia and the Aeranthes look like fungal spots to me. I am not so sure about the other spots or how to treat these spot if they are fungal.

What should I do? If the spots are not going to hurt the plants, I would prefer to wait for new leaves.

I also have a myriad of fungicides including Aliette at my disposal.