Using Extension Phosphorus Uptake Research to Improve Idaho\u27s Nutrient Management Planning Program

Irrigated silage corn is the main crop used for P removal in southern Idaho; however, little is known about the actual amounts of P removed under southern Idaho growing conditions. The study surveyed P removal by irrigated silage corn in primarily manured southern Idaho fields and wide-ranging soil test P. Whole plant corn tissue P concentrations ranged from 0.116 to 0.307% total P and averaged 0.208%—lower than Natural Resources Conservation Service (NRCS) estimates used prior to 2007 (0.26%P) but higher than estimates used since 2007 (0.185%). The study was used to update the OnePlan.org© Nutrient Management planning online program

Phosphorus Removal by Silage Corn in Southern Idaho

Corn silage is the predominant crop in Idaho used for recovering phosphorus (P) that has accumulated in soils from dairy manure applications. However, little is known about how much P and other nutrients are being recov- ered under Idaho conditions. The objective of the study is to estimate P removal by irrigated corn silage crops cultivated throughout southern Idaho with variable soil test P concentrations, and to identify effects of increasing soil test P on tissue concentrations of P and on plant P uptake. Forty-two different corn silage fields in 2008 and 2009 were selected throughout southern Idaho for soil and whole plant sampling at harvest. Soils were ana- lyzed for Olsen P, plant tissue was measured for total P content, and dry and wet yields were calculated based on field weights and drying of plant tissue

Soil–Plant Nutrient Interactions on Manure-Enriched Calcareous Soils

Growers working with manured soils o? en rely on soil test information when developing nutrient management for their crop, especially when manure application information is unavailable. Nutrient-enriched soils, like manured soils, can trigger nutrient de? ciencies and toxicities due to plant–soil nutrient interactions. ? e goal of the study was to determine correlations between soil test and plant tissue nutrient concentrations for irrigated corn silage crops (Zea mays L. subsp. mays) with varying nutrient concentrations unique to dairy manure-enriched calcareous soils. Whole plant and soil samples were collected from 39 cooperator corn silage ? elds at harvest over a 2-yr period throughout the Snake River Plain region of southern Idaho. Soils were sampled to a depth of 30.5 cm and analyzed for plant available forms of P, K, Ca, Mg, Na, S, Zn, Fe, Mn, Cu, and B; whole plant tops were analyzed for total N, P, K, Ca, Mg, Na, S, Zn, Fe, Mn, and Cu. Signi? cant positive correlations were detected between soil test K and tissue K (Spearman’s rho correlation coe? cient = 0.63), soil test K and tissue N (rho = 0.59), and soil test B and tissue N (rho = 0.53). A significant negative correlation was detected between soil test Fe and tissue Mn (rho = –0.59). Controlled studies are needed to corroborate the relationships observed in this survey study

Using extension phosphorus uptake research to improve Idaho's nutrient management planning program.

Irrigated silage corn is the main crop used for phosphorus removal; however little is known about the actual amounts of phosphorus removed under southern Idaho growing conditions. The purpose of this study was to survey phosphorus removal by irrigated corn grown for silage in southern Idaho under variable soil test phosphorus concentrations. In this survey whole plant corn tissue phosphorus concentrations ranged from 0.116 to 0.307% total phosphorus and averaged 0.208%, which is lower than Natural Resources Conservation Services estimates used prior to 2007 (0.26% phosphorus) but higher than estimates used since 2007 (0.185%). The study was used by NRCS to update nutrient management planning software used by planners in Idaho

Crossing Boundaries with Teamwork and Economics for Water Management

The Water Team used teamwork and economics to transcend water boundaries. Recommendations implemented and physical improvements extended the irrigation season by 16 days in 2008, increased potential farm profits, and increased water conservation. The Team is now poised to cross more boundaries, assembling data and coordinated plans for watershed management and groundwater recharge for larger geographic areas, watersheds, and organizations

Phosphorus Removal by Silage Corn in Southern Idaho

Corn silage is the predominant crop in Idaho used for recovering phosphorus (P) that has accumulated in soils from dairy manure applications. However, little is known about how much P and other nutrients are being recov- ered under Idaho conditions. The objective of the study is to estimate P removal by irrigated corn silage crops cultivated throughout southern Idaho with variable soil test P concentrations, and to identify effects of increasing soil test P on tissue concentrations of P and on plant P uptake. Forty-two different corn silage fields in 2008 and 2009 were selected throughout southern Idaho for soil and whole plant sampling at harvest. Soils were ana- lyzed for Olsen P, plant tissue was measured for total P content, and dry and wet yields were calculated based on field weights and drying of plant tissue

Using extension phosphorus uptake research to improve Idaho's nutrient management planning program.

Irrigated silage corn is the main crop used for phosphorus removal; however little is known about the actual amounts of phosphorus removed under southern Idaho growing conditions. The purpose of this study was to survey phosphorus removal by irrigated corn grown for silage in southern Idaho under variable soil test phosphorus concentrations. In this survey whole plant corn tissue phosphorus concentrations ranged from 0.116 to 0.307% total phosphorus and averaged 0.208%, which is lower than Natural Resources Conservation Services estimates used prior to 2007 (0.26% phosphorus) but higher than estimates used since 2007 (0.185%). The study was used by NRCS to update nutrient management planning software used by planners in Idaho