The objective of this study was to examine interception by creosotebush (Larrea tridentata [DC.] Cov.) of artificially applied rainfall for improved understanding of this phenomenon in hydrologic processes. This research was conducted near Las Cruces in southern New Mexico.... It was determined that leaf area was most highly correlated with rainfall interception, followed by number of stems, crown canopy area, and weight of over-dry leaves..... The annual rainfall in the southwestern U.S.A. is produced from storms of small amounts. Thus, interception by desert shrubs is of significant importance, since a high percentage of precipitation from these storms is "lost" from interception and subsequent evaporation back into the atmosphere. Twenty percent of the artificially applied rainfall was intercepted by creosotebush. For the native stands of creosotebush that had 30% crown cover, the loss of rainfall by interception would equal 22%. These data clearly demonstrate that light showers (<5 mm) do little to replenish soil water.

Lexington, Ky