I called my State Farm agent yesterday to inquire about coverage on my tractors. They are covered under my homeowners policy for my use on my land. They are not covered if someone else uses them, if I take them off my land, or if I use them for commercial purposes. While the land is in agriculture use, it's hay and a farmer does all the cutting. I keep the place tidied up and keep the field edges clean but since that's not directly related to agriculture and is more a keep the value of the property up (just like mowing a lawn) it's OK. I explicitly asked about the tractors and gave their values (this is a JD 4520 with cab). BTW, we have home, auto, and an umbrella with them and don't claim things unless it's over $2500 or so.
So for this casual tractor user / weekend warrior that's all I need, and it's another good reason not to loan anything out.
Pete