Sudden insect invasion on grain

Asked September 3, 2018, 5:08 PM EDT

I can’t take a macro picture so I’ll try to fill in the descriptions with less than 1000 words. I plant for butterflies pollinators and birds. Only tomatoes for myself to consume. I allow some of the sorghum and millet under my bird feeders to mature each fall. Mostly for the resident gold finches to eat and the insects that overwinter in the stalks. I only have room for a few and don’t want them to be ruined. Just lately the corner plants are covered in life and it’s spreading. I need advice from from someone knowledgeable about the pests of these crops. Saturday I noticed a slew of what looks like eggs exposed on the leaves. Today Monday the same plant also has a too healthy colony of very dark green aphids in the base of the leaves and what from a distance could be white flies or mites further out. But upon closer inspection do not move and aren’t purely white. If those plants had bloomed or were closer to ones that have I’d assume it was pollen without a second look, except it doesn’t dust off easily even far from where I’d expect honeydew. At least 3 sizes of ants are running up and down that will probably doom any lady beetle larvae I could relocate. Tachinid flys abound, probably anticipating caterpillars. I know they’ve hit my monarchs hard. Tiny black bugs (flea beetles?) dispersed quickly but no noticeable leaf damage yet. The tiny flyers were also too quick to get a clear shot of or identify. Wasps? Gnats? Same with a unfamiliar insect that appeared to have pinchers like a beetle and rear legs capable of jumping like a cricket. If those eggs are beneficials I’ll try the 20% milk I use for milkweed aphids. It doesn’t seem to harm monarch eggs or caterpillars. If whatever hatches will is there another plant family I can try to relocate them to, further from the butterfly hosts? I mostly have native flowers and trees but fight too many invasives to list. I’ve also seen sad evidence of wasps laying in all life stages before the butterflies eclose this year. I can’t rear all of them inside. I’m trying to figure out which species of wasp and flies but don’t know how long they will take to hatch from the eggs or bodies. Can anything else organic and feasible be done? H2O2? I’ll only tear them out if I need to. And only destroy any native life that gets out of balance. Thank you for your time and help.


1 Response

Okay, there's a lot going on with you question. First, with the picture on the left, those are was is left behind after aphids have been killed by wasps. These are aphid mummies and you can see the round holes in the back where the wasps have emerged. The glistening is honeydew produced by the aphids which will attract ants and tachinid flies as food for them. The next two photos look to be corn leaf aphids, which will infest corn and sorghum. The white things that don't move and look like whiteflies are the shed cast skins from the aphids when they molt as they grow.

What I would recommend is using insecticidal soap if needed to control the aphids. This will not have an effect on the monarch caterpillars or bees.