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Show XXII. Make a Model of a Conservation Farm or Ranch Building a model of a conservation farm or ranch is an excellent culminating activity following a yearlong study of soil and water conservation. Such an activity provides students with first- hand knowledge of the various soil and water conservation measures and their flood- control features. A model is the kind of activity in which all pupils in a schoolroom can participate. It should be planned in detail under your guidance as teacher. Decide what construction materials are needed, what soil and water conservation measures are to be applied, and how structures such as dams, terraces, bridges, fences, and buildings are to be modeled. The assignment of various construction details on the basis of age and grade makes it possible for all the children to share in the work. In making plans for this project consider the sources of outside information and assistance. Where can you find out what the local soil- erosion problems are and what conservation measures are in use^ What visual aids and references are available? Local representatives of State and Federal conservation agencies and organizations, including conservation farmers and ranchers, can be helpful. The model can be a replica of the general terrain of the community in which the school is located. Or you can select a nearby farm or ranch that the class can study firsthand. Let the students see the erosion problems, then build a model showing the land as it should be used. Models are usually built of fiber insulation board, papier mache, or a salt- flour mixture on a sturdy base. One good method is to use pieces of thick fiberboard cut to match the outlines of the different contours of the land. The pieces are stacked in the order of succeeding elevations and glued together. The edges of the layers are then filed off with a wood rasp to make the slopes smooth and even. If you want to make a model of an actual farm or ranch, your first step is to get a contour map of it. You can see the local Soil Conservation Service technician for sample maps of local farms. He can also give you suggestions about reproducing the contours to scale on the model. If the terrain is flat you may need to exaggerate the steepness 2 or 3 times. Make a base for the model from 1- inch lumber the size and shape of the farm. An 80- acre farm could be 2 feet by 4 feet. The first layer of insulation board should be the same size as the base. Then cut the succeeding layers according to the contour lines and glue them together. You may be able to save material and reduce the weight of the model by having the layers overlap only a little so that the inside is hollow. Plastic crack filler or papier mache may be useful during the final shaping. You may want to make some minor cuts and fills for roads, gullies, and other physical features. As the first step in decorating the model, paint it with glue. While the glue is still tacky, sprinkle screened sand over it. This surface has a texture that will make it look like fields and pastures when painted suitable colors. In deciding on the scale for the other items on the model, it is a good idea to start with the buildings. They need not be the same scale as the land; usually they can be somewhat larger. But other items such as fences, machinery, and livestock should be in scale with the buildings. Buildings- Cut buildings from balsa or other softwood. You can do some carving but windows and doors can be painted in. Fences- Drive dark nails or pins for fence posts and cut them off at a suitable height. For barbed wire, use fine wire fastened by a loop around each post. For woven wire cut strips of screen and push them into the modeling material; fasten with airplane glue. •^ W^^ k Iff... . ;; • P> t} u • • ^ " i-^^ gj fijtes^. » """.^ « iitfS8 Layers of fiber insulation board, cut according to contour lines of the land, are being filed down to form the hills and valleys for a model farm. 28 |