Table 2-2 Pre-plant soil sample (0-15 cm) chemical properties, 2013 and 2014. Soil Total Organic Year NO3-N§ P¶ K¶ N# C# Location† pH‡ --------------- µg g-1 --------------- ----- mg g-1 ----- 2013 Efaw 6.0 8.4 1.7 18.4 106 1.2 10.2 LCB 6.1 6.2 5.3 24.2 139 1.1 9.5 2014 Efaw TBD TBD TBD TBD TBD TBD TBD LCB TBD TBD TBD TBD TBD TBD TBD Efaw, Oklahoma State University Agronomy Research Station near Stillwater, OK; † LCB, Oklahoma State University Agronomy Research Station west of Stillwater, OK near Lake Carl Blackwell 1:1 soil water ‡ § 2 M KCl extract (Mulvaney, 1996) ¶ Mehlich III extract (Mehlich, 1984) # Dry combustion (Schepers et al., 1989) Table 2-3 Corn N fertilizer recommendations from the OSU generalized algorithm based on farmer practice NDVI and N rich strip NDVI from wheat and barley indicator crops compared to the agronomic optimum N rate for Efaw and Lake Carl Blackwell (LCB). N Farmer Rich Generalized Growth Practice Strip Algorithm N Location Crop NDVI NDVI AONR§ Stage† recommendation‡ Efaw Wheat 3 TBD TBD TBD TBD 4 TBD TBD TBD TBD 5 TBD TBD TBD TBD 7 TBD TBD TBD TBD 10 TBD TBD TBD TBD 10.5 TBD TBD TBD TBD Barley 3 TBD TBD TBD TBD 4 TBD TBD TBD TBD 5 TBD TBD TBD TBD 7 TBD TBD TBD TBD 10 TBD TBD TBD TBD 10.5 TBD TBD TBD TBD LCB Wheat 3 TBD TBD TBD TBD
Table 2-2 Pre-plant soil sample (0-15 cm) chemical properties, 2013 and 2014. Year Location† Soil pH‡ NO3-N§ P¶ K¶ Total N# Organic C# --------------- µg g-1 --------------- ----- mg g-1 ----- 2013 Efaw 6.0 8.4 1.7 18.4 106 1.2 10.2 LCB 6.1 6.2 5.3 24.2 139 1.1 9.5 2014 Efaw TBD TBD TBD TBD TBD TBD TBD LCB TBD TBD TBD TBD TBD TBD TBD † Efaw, Oklahoma State University Agronomy Research Station near Stillwater, OK; LCB, Oklahoma State University Agronomy Research Station west of Stillwater, OK near Lake Carl Blackwell ‡ 1:1 soil water § 2 M KCl extract (Mulvaney, 1996) ¶ Mehlich III extract (Mehlich, 1984) # Dry combustion (Schepers et al., 1989) Table 2-3 Corn N fertilizer recommendations from the OSU generalized algorithm based on farmer practice NDVI and N rich strip NDVI from wheat and barley indicator crops compared to the agronomic optimum N rate for Efaw and Lake Carl Blackwell (LCB). Location Crop Growth Stage† Farmer Practice NDVI N Rich Strip NDVI Generalized Algorithm N recommendation‡ AONR§ Efaw Wheat 3 TBD TBD TBD TBD 4 TBD TBD TBD TBD 5 TBD TBD TBD TBD 7 TBD TBD TBD TBD 10 TBD TBD TBD TBD 10.5 TBD TBD TBD TBD Barley 3 TBD TBD TBD TBD 4 TBD TBD TBD TBD 5 TBD TBD TBD TBD 7 TBD TBD TBD TBD 10 TBD TBD TBD TBD 10.5 TBD TBD TBD TBD LCB Wheat 3 TBD TBD TBD TBD