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Show Plants respond to environment Plants respond to their own local environment. L About the home garden one can find a wide variety of climate conditions, and an important part of garden planning is the identification of the variations. Such a study is called a microclimate survey. In analyzing the microclimate about the home, the tools needed are quite simple: a good eyesight and a 1 rapid response dial type thermometer with an eight inch stem such as the windshield thermometer used in California orchards. This thermometer is a sensitive instrument with a two inch dial now manufactured by Weston Instrument Corporation. Using this thermometer ther-mometer one can determine quite readily the temperature tem-perature of the soil, water or atmosphere as desired at any specific location. One of the more important considerations in reference to the growth of most plants is sunshine. The shading influence,,, of.tjeeg,, shrubs, walls and fences has a marked influence.pn.the. development f I many crops. A survey of the influence of such otr" structions to sunlight can be made at any time, but one must remember that the elevation of the sun varies with the season of the year. Hence, the area covered by the .shade from an obstruction will vary correspondingly. At 40 ' degrees north latitude, the following relationships will hold. To determine the length of the shadow cast by a solid fence, wall, shrub or tree at solar noon, that is the time the sun is at its highest elevation above the horizon for the day, multiply the height of the object by the following numbers as determined from the nearest date. |