This study empirically examines the effects of two different prominently displayed appeals in combination with set confidentiality assurances and other survey statements on completion rates for agricultural screening questionnaires. The experiment was carried out on a sample of 13,000 farm units, using person name and business entity (farm name) addressed pre-notification letters and mail back questionnaires. While web surveys have become increasingly more common in research, this methodology has not been thoroughly investigated for agricultural populations. Whether web can be an effective methodology for reducing more expensive in-person interviewing and land visits for determining eligibility for the Agricultural Census is evaluated. A critical question in this research was whether a prenotification letter asking respondents to complete a short 5 minute web screening questionnaire about their agricultural involvement could be effective. Also of interest was whether benefit appeal differences would hold across mixed mode (web, mail, and telephone) administration and whether systematic differences would contribute to coverage differences and response effects.