Historically, manure has been recognized as an excellent soil amendment that can improve soil quality and provide nutrients for cop production. In areas of high animal denisty, howver the potentail for water pollution resulting from improper storage or disposal may be significant. The objective of this tudy was to determine the P balance of cultivated soils under barley production that has received long term annual manure amendments. Non-irrigated soils ta the study site in Lethbridge, Alberta have recived 0, 30, 60 or 90 Mg manure per hectare while irrigated plots received 0,60,120, and 180 Mg per hectare annually for 16 years. The amoount of P removed in the barley grain and straw during the 16 year period was between 5-18% of the cumulative manure applied. There was a balance between P applied in the manure and P removed from the crops and soils of non-irrigated plots during the 16 year study period. In irrigated plots, as much as 1.4 Mg P per hectare added was not recovered over 16 years, and was probably lost due to leaching. The risk of ground water contamination with P from manure was higher with iirigated soils than irrigated plots that have recived long-term manure amendments. Manure application rates should be reduced in non-irrigated plots to more closely mantch P inputs to match crop P requirements.