Guidelines for the use of the pre-sidedress soil nitrate test (PSNT) have been established in sweet corn (Zea mays). Similar guidelines should be useful to growers in optimizing nitrogen (N) use in other vegetables. The purpose of this work was to establish a soil N threshold for butternut squash (Cucurbita moschata), above which there is no positive crop response to additional N application. To test crop response to sidedress applications of N over a range of soil nitrate levels, plots were established in pairs in commercial butternut squash fields. Six-inch sample cores for the PSNT were taken several days prior to sidedressing, which is about the time the vines start to run. Sidedress N applications were made by the grower. In each field, one plot received no N and the other received N at 50 kg·ha-1. The yield of the plot with the N treatment was compared with the nontreated plot. In fields where the PSNT values were at or above 68 mg·kg-1 N, plots receiving sidedress N had lower yields than those receiving no N. In fields with N levels at 41 mg·kg-1 or lower, there generally was a higher yield in the sidedressed plots. None of the fields in this study had N levels between 41 and 68 mg·kg-1 at the time of sampling, but it is likely that the threshold is within this range. E-mail howell@umext.umass.edu