Potential Water Use Conflicts Generated by Irrigated Agriculture in Rhode Island

In recent years agricultural practices in New England have undergone dramatic changes. Traditional dryland crops such as potatoes and silage corn have been replaced by irrigated “landscape” crops; specifically turf and nursery crops. For example, commercial sod production in Rhode Island has risen from 200 acres in 1972 to over 2,500 acres in 1986, while potato acreage has shown a similm decline over this period. Landscape crops command high market values and appear to represent along term trend inland use for the relatively densely populated southern New England rural areas because these crops can compete with residential uses for high priced land. Landscape crops have shallow root systems (15–20 cm) that utilize only the moisture in the upper portion of the soiI profile. Drought stress regularly occurs in turf and nursery crops planted on loam and sandy loam soils. Epstein has estimated that drought stress on these shallow rooted plants can occur after only 4 days without rain in the summer for sandy loam soils and after 6 days without rain on silt loam soils. Supplemental irrigation is becoming increasingly common in southern New England. Typical application rates for turf farms are 1 inch per week. This implies water use