Are aphids always bad?

I see a lot of information on aphid damage and how to eradicate them, but can they be benign or even good? These pictures are of a squash plant in a no-till bed in zone 7b. The bed is a layer of leaves, a layer of rotting forest floor wood, and some wood chips filling in the gaps. The rotting wood came with all manner of ants, beetles, larvae, fungi, etc. Nothing was intentionally killed; this bed is an experiment in trying to keep everything as natural as possible under my conditions. The seeds were directly sown.
This squash is significantly larger than the others in the bed. It has had large black ants apparently farming aphids on it since it was about 6" tall. The squash plant right next to--indeed touching--it is the second largest plant and it has small black ants farming what appear to be the same type of aphids on it. The ants do not cross between plants. The larger plant is quite infested. I see no indication of any stress on these plants whatsoever. I know everything in nature has its place, but not necessarily to help us. Are the ants fertilizing the plant? Does aphid farming help plants while just unchecked aphids destroy them? I found it interesting, and as long as the plants look healthy will not intervene.

I doubt it's good, but i am watching the ants as well. I moved aphid larvae onto it, they were running for their lives, the ants were swarming all over when they discovered it. But the ladybugs they leave in peace. Don't know what is going on. Maybe it's that the ladybugs just fly off or they're like little tanks, all strong and smooth, the ants can't hurt them. But they seem not to mind each other. The infestation is pretty bad this year in the two year old production field. I just select for resistant plants when i save seeds.
My house garden has not a lot to suffer. Once it was terrible on my peaches, i let it go, and waves of different predators came and went, taking hold in my biodiverse garden with places for insects to overwinter. Despite the peaches bearing no fruit i haven't noticed an aphid infestation on them so far. The only one bearing loads is the hops, which is as well the place i go to if i need ladybug larvae to destroy an infestation on some weak plant i don't have lots of seeds from yet.
I don't know if i feel the same in future, i might be selecting for hard skinned slow growing bitter tasting veggies, but for now, all is well.

Personally I see most "pests" as benign - they usually, in my experience, indicate plants which are stressed in some way.

A healthy garden ecosystem will always have a few aphids providing food for the population of aphid predators.

I am with Tyler in that it is a sign that the plant is stressed.

I only leave them when there is a predator to take care of them.  They are easy to get rid of and I would rather see the plant use its energy producing fruit.

Most of the time, I don't worry about them. I have them in my greenhouse right now, and that's a pain, because not all insects can easily get into the greenhouse, so some natural predators are absent. As far as squash in particular, I don't like aphids on my squash blossoms because they are not so good for eating at that point. The blossoms are so fragile that cleaning aphids off of them while keeping them intact is virtually impossible. But with artichokes, in my experience, aphids are inevitable and don't take away from the taste at all.

Stacy Witscher wrote:Most of the time, I don't worry about them. I have them in my greenhouse right now, and that's a pain, because not all insects can easily get into the greenhouse, so some natural predators are absent. As far as squash in particular, I don't like aphids on my squash blossoms because they are not so good for eating at that point. The blossoms are so fragile that cleaning aphids off of them while keeping them intact is virtually impossible. But with artichokes, in my experience, aphids are inevitable and don't take away from the taste at all.

I've been meaning to try the blossoms, but keep forgetting about them being edible. I found it interesting how they completely cover the male flowers but avoid the female flowers and the fruit. I had polination problems last year, but it seems like they are getting polinated well, possible by the ants roaming the plants constantly. But there's also been plenty of flying polinators so far this year.

I can tell you that my young plum tree had a terrible infestation of aphids two years ago, but the local sparrows soon discovered them and were constantly in the tree pecking away;  the goldfinches and blue tits also joined them on occasion and all were a joy to watch.  Last year there were some aphids, but the birds were still hard at work and this year there's almost no aphids left.  The tree looks great.

I've also seen sparrows on my roses and chard, stripping off aphids.  To me, aphids--and other so-called pests--are a part of the garden, just like the birds.  If I didn't have them, the birds wouldn't hang around either.