outdoors

BRAINERD, MINN. - Last week, on a warm and sunny afternoon, I used a handheld Global Positioning System (GPS) to determine the exact acreage of a wildlife opening I had cleared earlier this winter on my property.

To accomplish this, I simply picked a starting location on the perimeter of my newly created opening, pressed a few buttons on my GPS, then walked the outskirts of the opening. As I walked along, I watched the screen on my GPS and, like magic, my track was plotted. When I completed the loop, I pushed another button on my GPS and presto, I had the exact acreage of the interior of my route. My kidney bean-shaped opening was .2 acres, about one-third smaller than I had guessed.

This GPS method of area calculation will work no matter the size or shape of the area, and the results can be displayed in just about any format, from square feet to square miles, even metric dimensions. No measuring, no pacing, no mathematics, nothing.

Later, when I returned home, I drew a rough outline of the opening on an aerial photo of my land, named the opening, and then jotted down the acreage on the aerial map so I can refer to this information in the future. I also saved a version of this document in my computer.

Wow! I must be an electronics wizard, right? Wrong. I had my GPS owner's manual in my pocket, and yes, I did refer to it. But actually the process was simple.

Acreage calculation via GPS might not be news to modern farmers, but most recreational landowners I have spoken with are not aware that GPS units feature this time-and-money-saving option.

Why, you might wonder, did I want to know the exact acreage of the opening, and why did I not just make an educated guess?

Ultimately, my plan is to convert the opening to a food plot for deer and other wildlife, and knowing the exact acreage will help me determine the proper amount of lime, fertilizer and seed needed to produce a quality plot. Guessing at the plot size is not a good idea because overestimating the size will waste money on excess chemicals and seed, and underestimating will result in insufficient applications of the same, compromising the quality of the plot.

When the snow melts and the ground thaws, I will take a soil sample from my plot, send it in for analysis, and since I now know the exact acreage of my plot, I'll use the results of the soil test to determine the proper amount of lime, fertilizer and seeding rates needed to efficiently and economically grow the plants I choose to employ.

Since natural gas is used to produce fertilizer, prices are high, and, as we all know, so are fuel prices. Thus it is more critical than ever to get it right the first time.

A landowner can also use this GPS acreage-determining technology to gauge how many trees to order and plant when reforesting a given space.

Say you have determined by using a GPS that an odd-shaped portion of your land covers 2.3 acres. You intend to plant, for example, oak seedlings in that location. Your forester or tree nursery technician has recommended you plant X number of oak seedlings per acre for optimum results. Then, simple math (2.3 times X) will determine the exact number of trees you need to order.

Most modern GPS units have the ability to gauge acreage. Garmin makes my GPS, and the acreage computation option is called "area calculation." It is found under the "tracks" menu. If you study the owner's manual for your GPS and cannot find this option, don't be discouraged. Modern GPS units include so many options that any specific feature often gets buried. I knew my GPS featured area calculation and I still had trouble finding the instructions in the owner's manual, and the index was of no help.

If you have misplaced your GPS owner's manual, a downloadable PDF version can usually be found on the company's website. Look under the "Support" section.

If you still don't know whether your GPS is capable of area calculation, contact "support" at the company's website.

Bill Marchel is an outdoors photographer and writer who lives near Brainerd, Minn. • bill@billmarchel.com