From time to time a choice metal detecting site will be so large that it presents a problem to the detectorist. If you were a relic hunter looking for relics over a large area or intent on searching out some long lost buried loot it is a formidable problem when you don't want to miss the best target in the area by weaving a trail like a drunken snake. Yet so many may walk away from the hunt of a lifetime by doing just that.
To hunt a large field may take more than one day but you should be prepared for that. When you are hunting for an unknown target always hunt in all metal with the sensitivity as high as it will go. Use the largest coil that you can get to probe as deep as you can. Extend the rod on your detector so that you can sweep up to eight feet at a time and this will shorten the time it takes to hunt. The point is not to miss one square foot of the area but to cover all of it and look for indications of old buildings by looking for large numbers of nails. Square nails were used in most 19th century construction and look for small scraps of lumber that may be all that is left of an old building. The old timer's didn't have lumber available at the corner lumber yard to build with and almost all old buildings that were abandoned were robbed of their boards until nothing was left but some scattered nails.
To work a pattern in these areas and do it correctly you will have to use pins that you can stick into the ground at each end of the field. If the field covers several acres then the pins might be exchanged for poles with small flags attached but normally just pins like rebar construction iron are good for this purpose because they are easy to jab into the soil even if it is very hard. A good idea is to cut two pieces of 5/8 inch rebar to about three feet and then paint them with a bright color that could be seen at a distance. Place these at the start and finish of the first row you scan and when you get to the end of the row pull it out and place it for the next row. This will aid your spacial talents and you will not waste time overlapping your scans or miss anything valuable. This will give you the peace of mind that you have checked every square foot of the area and the best chance of finding your treasures.
Do not discard metallic objects when you find them but put them in your sack for later. Once you have completed the field you can analyze all of the objects and put together an idea of what kinds of activity has gone on here in the past. It may in fact show that an area of promise is just at the edge of the field and you might extend your search there to locate what you are looking for. When you dig up an object also pick up any broken glass pieces or bottles that you uncover as you might be able to find something you can date from them.
To make a good job even better use a Notepad to mark the areas where you find things of interest. It may be that you can come back someday with a detector that will go even deeper.
If you are looking for a old building site is a very large area then look for piles of rocks which were used in the 19th century for boundary markers or very large trees. Look for depressions or mounds that might be unnatural but if it is an old homestead then look for the water well. These wells were mostly hand dug shafts about five or six foot around and might be as deep as fifty or seventy five feet. Sometimes wells were covered with boards to keep out the critters that usually fall into them like frogs and snakes and may lie under a covering of dirt. Be careful not to fall into one! While I make mention of wells I would also warn you about homes that used septic tanks. If you think that you have a problem just fall through into one of these! I have hunted around old homesites and seen septic tanks where someone has fallen into them by accident; it isn't pretty. I have noticed that when a field is plowed it will generally show traces of activity after a rain. There will be exposed pieces of glass bottles of all different colors glimmering in the sun and either this was an old homesite or close to one because it could be the remains of an old trash dump. Hunt a circular pattern around the center of the glass area and look for nails first to locate the homestead.
The funny thing about field hunting is you might hunt a long time and hear nothing and then find something new or something surprising. For instance I hunted a field and only found a few nails then a recent quarter then a 60 year old cap pistol down about 9 inches deep with nothing around it at all! Makes you wonder how they got there.
