Good Morning - a question regarding writing magazine articles.

If I write a magazine article and promote XYZ Farm and, as a direct result, they make money from my article...is it fair for me to ask for payment for the mention? Payment meaning goods and services and not actually dollars.

I'm not trying to be greedy but I am trying to be fair to everyone...self included.

I've never before included other "companies" in my articles so don't know what is acceptable and what isn't.

Thanks,