Figure 1. A vegetable field composed of plastic mulch covered rows and uncovered row middles in which tht total area of the block is 1 acre (43,560 sq ft) in size. If the plastic covered rows are 3 feet wide and the row spacing is 6 feet, then the filed area under plastic receiving fumigant treatment is actually only one half acre in size or 7,260 linear feet of row. Assuming a maximum broadcast application rate of 350 lb/a, then only 50% of the acre will receive fumigant treatment, and the amount of fumigant applied within the block or acre of field is 175 lb/a. The correct expression of application rate for this scenario is 175 lb/a and/or 350 lb/treated acre. Treated acre meaning area of actually treated land and not cropland covered. The broadcast equivalent of this in-row application is also expressed as 350 lb/a or 350 lb in 14,520 linear feet of row 3 feet wide.