Yes and no.
You should attempt to cause the least amount of suffering. But I don't believe you have that much of a moral obligation to avoid causing accidental or incidental suffering. That is why they are called accidental and incidental. As usual, I fall back on the accepted definition of vegan, "A philosophy and way of living which seeks to exclude—as far as is possible and practicable...." Please notice that it uses the words "possible and practicable". It does not use the phrase "at all costs".
In the justice system you are not legally responsible for accidental deaths unless there was some reasonable way you could have prevented it. If you run someone over when your brakes fail and your car not been properly maintained and you were warned, then you are criminally negligent. but if you run someone over because your brakes fail because the mechanic put them in wrong you are not liable.
Now we can buy produce that was farmed without pesticides. It's actually pretty easy to do. Those foods are called "organic" and in the USA and the UK that label is controlled by government agencies that provide both requirements and inspections. I'm not sure vegans are "obligated" to buy organic. But you certainly can choose to. it is certainly possible and practicable.
As far as intensive farming practices go, trying to avoid crops that have been farmed intensively is difficult - maybe even impractical. Small farms that don't intensively farm usually concentrate on expensive crops that need to be handpicked. Like strawberries. and there are other crops that can be found at "fruit stands" and farmer markets. Lettuce, string beans, corn. But I don't think you can live off just those things. I doubt you will find oats, wheat, or soybeans in a farmer's market.
I don't think vegans have a moral imperative to shop at farmer's markets but I like the concept both for environmental reasons and social justice issues. So I buy a lot of my produce at a farmer's market. It certainly falls into my idea of possible and practicable.
Concerning yourself too much about accidental or incidental deaths, well to paraphrase, that way madness lies. you go down that road and you have to start watching where you walk so you don't step on any ants. Also unless you want to live in the woods with just a garden you are constantly surrounded by incidental deaths of animals. The grocer you visit uses insecticides to keep fruit flys and pantry moths from becoming problems. your landlord and your grocer will poison rats, mice, and cockroaches. These things are pretty much unavoidable as long as you choose to live in the modern world. And I don't believe you are morally obligated to move into a cabin.
I might also bring up that the number of animals that die during harvesting operations is probably much smaller than you might think. There have been sevearl studies on this. At least one in England. Oh here (thank you google), is a blog that describes the research in an easy to read way.