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Several methods have been used to estimate movement of nitrogen below cropping systems including soil sample collection, suction cup lysimeters, drainage lysimeters, and resin traps. Each of these methods has advantages and disadvantages in the sandy raised bed production systems found in Florida. The objective of this research was to investigate each of these methods under drip irrigated production of squash controlled by a soil water sensor in Florida. Secondary objectives included evaluation of the soil water based irrigation control system and effect of N rate (82, 164, or 245 kg N/ha) on squash production. Calculated ET was 109 mm compared to seasonal irrigation depths of 66, 163 mm for I1 and I2, respectively. Corresponding overall seasonal averaged volumetric water content (VWC) were 0.106 and 0.133 m3/m3. However, neither N rate or irrigation treatments significantly affected yield. Soil solution nitrate concentration was higher for I1 compared to I2. This may be related to reduced leaching and dilution associated with under-irrigation. Based on results of soil samples and drainage volumes, estimated N leaching rates were 37, 21, and 33 for the low, medium and high N-rates, respectively. Increased N leaching with low N may be related to reduced plant growth and soil water extraction. Based on resin traps extraction, N leaching rates were lower and ranged from 5-18 kg N/ha which may be related to the apparent lack of deep percolation. Experimental results will be verified for peppers, tomato and squash during 2005.