Dairymen advised how to manage nutrients passing through their cattle

By MANDY JOHN | Central Texas Edition

Dr. Sam Feagley presents nutrient information to dairymen at Stephenville show. -Staff photo by John

September 26, 2002 -- The Texas Dairy, Farm & Ranch Show held Sept. 18-19, 2002 in Stephenville allowed dairymen to check out new and existing equipment, to visit the many vendors at the show, and to learn more about dairy farming at the seminars held at the event. One of the seminars given was on nutrient utilization.

"The Nutrient Utilization Plan (NUP) is the regulated nutrient management plan that the Texas Commission for Environmental Quality (TCEQ) has adopted," explained Dr. Sam Feagley, soil and crop scientist for the Texas Cooperative Extension. "It was developed by the Natural Resources Conservation Service and the Texas Cooperative Extension. The NUP was developed to work with producers to help them manage all nutrients, especially nitrogen, phosphorus, and potassium.

"There are environmental issues that must be addressed when dealing with both nitrogen and phosphorus. A major issue with nitrogen is when it reaches into ground water. If the concentration reaches 10 mg/L, nitrate can cause methemoglobinemia, also known as blue baby syndrome, in both fetuses and infants. Blue baby syndrome occurs when the baby is not fully developed because of nitrate and, in turn, does not get enough oxygen, which causes it to turn blue," stated Feagley.

"Another issue is runoff of nitrogen and phosphorus, causing the potential for eutrophication. This can lead to water tasting bad and can even lead to fish dying in the water. Everybody is contributing to the runoff problem, even large corporations. We all have a part in affecting the water quality.

"According to the TCEQ, the NUP must contain the recommended rate, methods, and schedules of application of manure and wastewater. It must also contain the crop types, the maximum crop uptake, and the expected yield of each crop. The last requirement is that it must contain the best management practices to prevent phosphorus impacts to water quality.

Feagley went on to list the various people who can develop a NUP:

• An employee of NRCS
• A Nutrient Management Specialist
• The State Soil and Water Conservation Board
• The Texas Cooperative Extension
• An agronomist or soil scientist on full-time staff of an accredited university located in this state (Texas)
• A professional agronomist or soil scientist certified by the American Society of Agronomy, after approval by the executive director

"The professional agronomist or soil scientist certified by the American Society of Agronomy can develop a NUP only after all the other people on this list have been notified and have tried to develop the NUP. Just remember that these people working on the NUP are trying to help you.

"There are different times when a NUP might be required. You might need it when the phosphorus concentrations exceed a certain number. The two extraction methods that you need to use are either the Mehlich III or Texas A&M University's extraction methods for phosphorus in Zone 1. One thing to remember is that the soil samples are different when effluent or manure are incorporated and when they are not incorporated.

"You must also remember that you have to be able to document putting in less phosphorus than before so that the test can be accurate. It may take several years, though, before it shows up on the soil tests that the phosphorus is less than before. And there is that 30 percent error in sampling.

"You might be asking yourself how can the NUP help me, the producer. Well, the NUP can help you in different ways. It can help you manage manure for phosphorus, it can help you estimate how much manure and effluent can be applied to the soil, and it can help you understand, and potentially implement the best management practices to reduce the amount of nutrient runoff."

For more information about nutrient management plans, go to: nutrientmanagement.tamu.edu or nmp.tamu.edu.