My wife and kids want me to plant some apple trees in our yard. I live on a 2 acre lot in the country surrounded by farmland. My question is how far do I need to plant the trees from the field to keep them safe from roundup, 2-4-d, etc., that is applied to the field?
Re: Apple trees
This is a tough question to answer because it depends on too many variables. If the farmer sprays on a windy day, the mist could reach your apple trees no matter where they are planted. Usually they don't spray on windy days though because those chemicals are very expensive and they don't want them drifting away. About 60' should do it for you.
If you see them spraying and suspect that it is getting on your trees, you can hose it off within an hour of spraying. Most herbicides are applied before apples leaf out so you should not really have a problem unless you have winter wheat followed by soybeans. Then the defoliant may be applied later, unless they do not bail the wheat straw, then they don't usually use any. The wheat straw left on the ground discourages weeds and mulches the beans.
Re: Apple trees
Another thing to consider is germination and gender- apples come in male and female varieties and while both will grow without the other, bearing fruit requires both be in range of the pollinators. Having other types of apple trees nearby can also affect the fruit, though there is usually a natural preference for their own kind so long as it is available. If you are that close and that concerned about the effects of someone else's spraying, you ought to consider living somewhere else because in farm country, overspray and run-off pesticide migration is going to happen- it goes with the location and the land use.