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DeBano, L.F., Rice, R.M., and Conrad, C.B., 1979, Soil heating in chaparral fires: effects on soil properties, plant nutrients, erosion, and runoff: Pacific Southwest Forest and Range Experiment Station, Berkeley, Calif., U.S.D.A. Forest Service Research Paper PSW-145, 21 p. In an attempt to determine the effects of prescribed burning on chaparral environments, researchers studied prescribed burns and one wildfire in Southern California between 1968 and 1975. Data on wildfIre temperatures (including temperature gradients and durations of heating) and descriptive information on vegetation and soils were used to generate stylized soil heating curves representing different burn intensities. These curves, in turn, enabled researchers to estimate the direct effects of fire on plants, litter, and soil ~ncluding chemical, physical, and biological properties), and the long-term effects on erosion, surface runoff, and hydrology. Although published research supplemented the results of this investigation, the authors note that historical measurements of maximum soil and fire temperatures do not adequately characterize heat pulses and time-temperature relationships. Information pertaining to water repellency in this paper is limited to a summary of previous research on the topic. DeBano, L.F., Savage, S.M., and Hamilton, D.A., 1976, The transfer of heat and hydrophobic substances during burning: Soil Science Society of America Journal, v. 40, no. 5, p. 779-782. This investigation addressed the role of soil moisture in fire-induced water repellency. Pine litter was burned over wet and dry sand for 5 and 25-minute trials. Out of the four treatment types, the 5-minute burning over dry sand produced the thickest and most intense water-repellent layer. The next most intense repellency developed in the 25-minute burn over wet sand. Although hydrophobic substances traveled the deepest in dry sand after 25 minutes, high temperatures destroyed some of the repellency in the upper layer. Water repellency was concentrated close to the surface in the wet sand trials, and was even shallower for the shorter burn period. Temperatures, however, did not get high enough to destroy repellency at the surface when sands were wet. The paper supplies information on the sequential development of temperature gradients at various depths within the sand prof11es, and on the subsequent intensities and depths of water repellency. Results of the analysis of organic matter and carbon content appeared to support the hypothesis (Savage, 1974) of natural fractionation of organic compounds with depth during burning. The authors also note that the presence of soil moisture appeared to interfere with this process. Thus, both polar compounds and extremely water-repellent substances were left near the surface of the wet sand, resulting in intense water repellency. The authors propose that the results suggest that in areas where water repellency is a problem, prescribed burning should be done when the soil is moist. 13