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

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

Comparing Three Different Methods for Assessing Corn Silage Density

Silage density is negatively correlated with dry matter losses in storage and has been used as an Extension evaluation tool to assess ensiling management practices on farms. We compared three methods for estimating silage density on 18 farms. Core sampling is the standard method, while the calculator and feed-out methods are new alternative methods. Core sampling results were highly correlated with the calculator method but not with the feed-out method. Core sampling and the calculator method are recommended tools for estimating storage dry matter losses and evaluating alternative ensiling management practices by Extension faculty, producers, and other users

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