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Twelve replicate individuals of two dominant shrubs, creosote (*Larrea tridentata*) and triangle-leaf bursage (*Ambrosia deltoidea*), were selected. Soil samples from the top 10 cm were taken from beneath the canopy of each plant in July (at onset of monsoon season), as well as twelve nearby interplant areas of unvegetated soil to represent initial conditions. The selected plants and bare soil then began receiving one of four precipitation treatments: 5 mm of precipitation (representing the average pulse size received at this site) or 7.5 mm of precipitation (representing a 50% increase in pulse size) delivered either every 2 weeks (rounding up the average frequency of pulses at this site) or every 4 weeks (representing less frequent precipitation events). The four treatments (5mm×2wks, 5mm×4wks, 7.5mm×2wks, 7.5mm×4wks) were applied to each of 3 replicates, totaling the 12 individual plants from each cover type. Precipitation treatments were applied using a backpack sprayer, delivering 1 L (for 5 mm) or 1.5 L (for 7.5 mm) of de-ionized water evenly to the soil over a 0.5-m diameter circle centered around the plant. The simulated precipitation events continued every 2 or 4 weeks until late in the monsoon season, ending in September when final soil samples were taken from beneath the canopy of each plant. Soil samples were sieved to 2 mm prior to analysis. Approximately 500 g of soil was weighed into plastic 1-L bottles and saturated with 95% ethanol to preserve the invertebrates. A modified heptane flotation method was then used to extract the arthropods from the soil. The ethanol from the preserved soil was decanted across a 38-µm mesh sieve, and the soil was then saturated with water and decanted three more times to ensure the preserved arthropods were rinsed from the soil across the sieve. The contents of the sieve (containing the arthropods) were thoroughly rinsed with water into a 2-L flask containing a stir bar, to which 20 ml of heptane was then added. The flask was sealed with a rubber stopper fitted with a hollow metal pipe that reached down into the flask below the surface of the water, ending just above the stir bar. The stir bar was spun to mix the heptane with the water containing the arthropods at 600 rpm for 20 minutes. The flask then settled for 5 minutes, allowing the heptane to float to the top carrying the arthropods. Water was drizzled through the hollow metal pipe into the bottom of the flask without disturbing the heptane layer, raising the level of the heptane so that it could be carefully removed from the flask and decanted across the sieve. The contents of the sieve were then rinsed into a sample cup using 70% ethanol. The soil and remaining water in the flask were decanted across the sieve, returned to the flask with another 20 ml of heptane to repeat this flotation process a second time, ensuring all arthropods were removed from the water. The contents of the sample cup were then identified and enumerated to the lowest possible level, which was Order for most taxa, as well as Class (immature Diplopoda, Pauropoda), Suborder (Acari), or Family (within the Collembola and Hymenoptera). The abundance of each arthropod taxa was then expressed as the number per kg of dry soil extracted. Gravimetric soil water content (SWC) was estimated by drying 25 g of soil at 105 degrees C for 48 h. Total and inorganic C and N were measured on soils ground to a fine powder in a Spex ball mill that were either left unacidified or acidified with HCl respectively. Samples were analyzed on an elemental analyzer (Perkin Elmer PE2400, Wattham MA). Electrical conductivity (EC; a proxy for salinity) and pH were measured on field-moist soil using a 5:1 or 2:1 water:soil dilution, respectively with an Orion 4-star pH and EC meter. Soil texture was measured using the hydrometer method.