I have a dwarf umbrella tree (I think) that is infested with scale insects (I think). I've sprayed 3 X with neem oil and I'm pretty sure I'm getting every leaf, but still the leaves continue to drop. It also has large bumps on the truck that I'm unsure if they are normal or part of the infestation. I'm not sure where to go from here, but I DO know that I don't want to lose the plant. Do you have any ideas?
Marion County Oregon houseplants
Thank you for your question. I am having difficulty seeing either the spots on the leaves clearly, or the 'bumps' on the trunk. Scale certainly are common on houseplants, including schefflera, but they are typically rounded and smooth, rather than bumpy. There are several causes of spots on leaves. Again, I cannot see whether they are insects or spots that are sunken. If they are scales, here is an article on how to deal with them on houseplants: https://extension.umd.edu/hgic/topics/scale-insects-houseplants
Here is an Extension article on the main diseases that can cause this: https://extension.psu.edu/schefflera-brassaia-diseases But, an insect sucking the leaf on the underside of the leaf can also cause sunken spots.
Are you able to take a better photo of the stem/trunk? It would be helpful if you could take a leaf and, if you can remove them, whatever is on the stem, and visit your county Extension office, where a microscope could be used. You can find their contact information on this webpage: https://extension.oregonstate.edu/marion
Hi, The link for the first publication was not working. We've fixed it and now it should be. Thanks!