They are some sort of greenhouse/flat-backed millipede. There are many families and species of those millipedes, some native to the US, others introduced, so I cannot give you a more specific identification. These are not carnivorous; they eat decaying plant matter. They are a constant presence in my compost, which is full of the decaying plant matter they feed on. They also often tend to end up in my container plants. Although I keep my plants on tables when outside, millipedes can apparently climb up metal table legs with no difficulty. I do not think they harm potted plants; I have seen no evidence that they do, though their presence might indicate that your potting mix has too much un-broken-down organic matter. Your picture looks pretty much like my compost, very wet with a mixture of broken-down and not broken-down organic material and a plethora of millipedes going about their business eating. I think that potting mix is more likely to harm your trees, particularly citrus, than those millipedes.
Topic: Found these in my citrus tree soil. (Read 887 times)