There are a couple of different alternatives for drawing your maps: 1. If you have two farms that are 10 miles apart don't worry about the distance. Draw the first farm and then draw the second farm to the side or above or below the first farm. When drawing the second farm leave some blank space between the two but don't worry about it being 10 miles. You just need enough space so that you can look at it and tell that the two farms are not connected. Sometimes a single line between the two farms works well as a reminder that they are separated by a larger distance.
2. If you are interested in keeping the maps to scale with accurate distances between each farm, then Farm Site will be your best bet. With Farm Site you can import USGS road & waterway maps for your farms. These maps have GPS coordinates built into them and will be imported into the proper places on your map. With Farm Site, all you have to do is line up your scanned ASCS maps with the roads and waterways (using a three point calibration process) and then trace your field boundaries. When you zoom to your entire farm it will cover 50 miles. However, you can set up "Defined Views" for each individual farm so that you can quickly zoom in on any individual farm.