Insecticidal soap gets rid of most any creepy crawly on plants.

If you do nothing what will happen depends upon the number of aphids (they will colonize on the plant if they are happy there) and the strength of the plant.

The aphids will suck juices from the plant. A low population won't adversely affect an otherwise healthy plant, but if the aphids colonize and make babies the plant will eventually die. Death could come from a pathogen an aphid is carrying or simply from exhausting the plant over time.

Long story short, you will want to manage this infestation. If you don't and their numbers grow they will likely spread out to other plants as well.

If spraying with insecticidal soap doesn't produce good results (it can be difficult to get the spray in every nook on a lush plant) you can mix some in a 5 gallon bucket and set the plant in it submerged for a few minutes. Repeat in a week as any eggs will still survive.

Wish we had a better handle on the 'shrimp-like' thing! Size? Behavior? Would be nice to be certain that it's not one of the beneficial predators. For example lacewing larvae could be described that way. ;-)

Take username's advice and get after the aphids pronto. Though they are typically not in the egg laying mode at this time of year, they each can bear several dozens live babies, which will (in turn) bear their own babies in a week or so. That's why aphid explosions literally happen over night!

If you find that you have lady bug populations (adult and larvae) as lacewings, you may want to use the old fashioned hand squishing method to get rid of some aphids. That way the beneficials can continue to do their work.

Here is a link that might be useful: {{gwi:45192}}

Very good point that the unidentified critter may be a natural control, Rhizo! If that is the case then I agree, hold off on the insecticidal soap. Just sit back and watch nature.

The shrimp-like thing is so tiny that I have to get a hand lens to identify it further, and I can't seem to locate one. They look white with longish legs. Very delicate seeming, like all legs. At first I thought it was dust or something, but it's all exactly the same. It may in fact not be an insect. What does aphid poop look like? This stuff is a fraction of the size of aphids. Like a mm at most. It's long and skinny and fuzzy, which I interpreted as legs but may be incorrect. It's definitely raised on these "legs" of of the leaf. Does that narrow things down? Could be eggs?

Ha! Very good description of the shed skin of an aphid! They shed them like crazy as they grow larger. I'll attach a picture of an aphid in the process. I am certain that this is what you've observed.......so get that insecticidal soap and get busy!!!!!!

Here is a link that might be useful: {{gwi:45193}}

I guess that it is that time of year. I was eating some lettuce wraps last night, using lettuce from my garden, and noticed a tickling on the back side of my hand. There were three aphids on my hand! I had washed the lettuce well, so it made me wonder how many had gone down the drain and how many I had already eaten.
I looked at the lettuce out in the garden, and didn't see any aphids. Any ideas on how to stop these aphids? I don't want to use insecticides and the plants are in the ground, so I can't dip and swish.

You can first try spraying the aphids off with a hose end nozzle.

You may have to do this every couple days.

Otherwise insecticidal soaps are food safe, they aren't toxic to people or animals as they aren't a "poison", they smother the bugs that breathe through their skin and also can breakdown the protective barrier of bugs that allows them to keep moisture in.

Another control option is to do absolutely nothing. Lettuce grows quickly and apart from a super heavy infestation can probably do just fine with the aphids helping themselves. I mean if lettuce can handle being trimmed and regrow it can handle some aphids.

Besides, the aphids just add a little protein to the lettuce ;-)

I remember when I was a kid my mother served a salad from the garden and she rinsed it well, but I felt something odd while chewing and extracted a green caterpillar from my mouth. Upon inspection there were many in the lettuce.

Grossed me out, but now I just figure bugs on vegetables is just natures way of helping us get the protein we need ;-)

Shed aphid skins. Cool! Makes perfect sense. I suspected that they were an aphid byproduct, but didn't know exactly what.

Gotta get me some soap!

Thanks!