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SOIL TEMPERATURES. 
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42. Soil temperature. Mich. Agr. Exp. Station Tech. Bull. 26. 1916. 
43 Fereel, Wm. Temperature of the atmosphere and the earth's surface. 
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46. Oscamp, J. Soil temperatures as influenced by cultural methods. U. S. 
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SOLAR RADIATION LIGHT. 
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55£. Burns, G. P. Studies on the tolerance of New England forest trees. 
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57. ■ II. Relation of shade to evaporation and transpiration in nursery 
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62. Kimball, H. H. Observations of solar radiation with Angstrom pyrheliom- 
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