Topographical Maps: |
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by E. Calvin Palfrey |
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| Planning an outdoor trip in the near future? Going back to old, familiar haunts that you know like the back
of your hand, or to new, completely strange territory? Hunting, fishing, hiking-whatever and wherever your outdoor
interest may be-topographic maps can add to the success and pleasure of your trip. Why is a topographic map useful to the outdoorsman? Primarily because it shows the position and shape of the landforms that influence the movements of both human and animal life. With a little practice in reading contours you can determine the height of each hill, the depth of each valley, and the approximate elevation and slope of the ground at any point. |
| Perhaps your interest is hunting and you are fortunate enough to make a preseason visit to a game area. Topographic
maps as "silent guides" will help you to find your way with ease and confidence. If such a trip is not
possible you can, in the comfort of your home, select hunting areas from topographic maps. The maps serve as a
tangible inventory of the physical characteristics of an area, and they provide data necessary to schedule the movements of individuals or groups of hunters. If you are a fisherman, you will find topographic maps useful for planning the best route to that special lake or promising trout pool. Perhaps you are fishing a very large lake from a boat and you're really pulling in the "big ones." |
| You know you've found the particular place on the lake where the fish seem to congregate, and you want to remember it. With a pocket compass and your topographic map, this is simple to do. First it will be necessary to identify two or more landmark features shown on the map. Then with your compass determine the bearing to those features. You will then plot these bearings on your map, but since they will be plotted from the points sighted, the bearings will be in reverse from what you have actually observed. The point at which the lines intersect will be your choice fishing spot. Because topographic maps show both natural and man-made features, they are useful to the hunter, trapper, fisherman- anyone who seeks the outdoors. Even the most inexperienced map reader will have little trouble identifying access roads, jeep and pack trails, or old logging roads. (Note, however, that trails shown on older maps may no longer be in existence.) |
| Fire lanes and similar clearings-good travel routes in heavily wooded country-are also shown. A green overprint distinguishes wooded areas, scrub, orchards, and vineyards from cleared land. Woodlands that provide cover for game and open lands that furnish feeding areas are easy to identify. Features such as jeep trails, fence lines, and fire lanes are generally shown only on the more recent maps. Here on topographic maps are the streams, springs, and ponds-the potential water- supply sources for all types of game. Swamps and marshes which are the haunts of deer, turkey, beaver, and muskrat are clearly identified by appropriate symbols. Also important to the sportsman are the bound- aries of public game preserves, and wilder- ness and wildlife areas shown on topographic maps. Dams, locks, falls, and rapids, depending on their sizes as well as the scale of the map, are generally easy to spot and locate. |
| In the preparation of recent topographic surveys of recreational areas, special attention is given to mapping
trails, camp- sites, springs, scenic overlooks, historic landmarks, and other features of interest to the sportsman
or tourist. How many maps will you need? That depends on the area you plan to cover and the scale of the map you select. To obtain the most detailed information and the most legible map detail, you will want to select the largest scale map available. Providing it does not fall on the map edge or corner, the area you would normally cover on foot during a day's hunting or hiking can be shown on a 1:24,000-scale quadrangle map. One inch on the map represent 2,000 feet on the ground; depending on the latitude, one map may cover about 60 square miles. The overall paper size of the map is approxi- mately 22 by 27 inches, and it can be folded to convenient pocket size. |
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Taken from a U.S. Geological Survey booklet |
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