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Soil FertilityMineral soilsThe most limiting plant nutrient on all of the soils of the area is phosphorous (P) . Soil testratings of 2 to 5 on virgin soils are common .* Farm soils that have been amended with manure orinorganic P fertilizers obviously have higher phosphorous soil test levels . Proper placement withthe seed at 2-3 cm below the seed for all adapted crops, along with maintenance of organic matterand proper pH, will. maximize the efficiency of P uptake and minimize P fixation .The lacustrine clay and silty clay soils generally have medium to high ratings for potassium(K) . Soil test results may call for low rates of K to be applied to ensure adequate K nutrition ofthe crop grown . Soils with very high silt contents generally have low K contents .Profitable responses to higher rates of nitrogen (N) applications may be obtained fromforage grasses (up to 200 kg N/ha) and small grains (up to 70 kg/ha) than may be obtained in moresoutherly parts of the province . This is attributed to the adaptation of these crops to the climateand soils, and to the low incidence of leaf diseases . These higher rates of application only applyto early seeding (prior to May 15) of small grains, and when P and ,K are applied to meet soil testrecommendations .More-than-adequate levels of calcium and magnesium are found in most soils, with theexception of the acid sands associated with the surrounding Precambrian shield, and soils withhigh silt contents (silt loam phases of Blanche, Pense, Falardeau, Evanturel, Earlton and Canesoils) . Sulfur is found at levels that are at least adequate for crop production .Manganese may be deficient on drained, fine-textured soils, particularly in years in whichJune and July are relatively dry .Many of the mineral soils have medium to slightly acid surface horizons, regardless ofcalcareous parent materials . Calcitic and dolomitic agricultural limestone is available in theimmediate area .Soils with surface pH values above 7 are not uncommon. Iron deficiency was found inraspberries grown on clay soil having a pH in the plow layer of 7 .6 . It is not economical to lowersoil pH values .Organic SoilsBarley, oats, timothy for seed, and alfalfa, have all grown successfully on organic soils inTimiskaming . There is little information available on the use of organic soils for the productionof field crops ; therefore, farmers rely upon soil tests for mineral soils and their own experiencesto determine the proper rates of fertilization on these soils .Nitrogen requirements for organic soils appear to be quite variable and difficult to predict .Trials conducted on farms by New Liskeard College ofAgricultural Technology, in the early 1980's,showed no yield response by barley to nitrogen . Along with N, micronutrient availability may varysignificantly from area to area . Manganese deficiency has been frequently observed .* Sodium bicarbonate phosphorous soil test (ppm) .28