Summer Silage Sampling Reminders

Adapted by Betsy Karle, UCCE Glenn & Tehama

By now, all dairy producers in the Central Valley are well aware that samples of each harvest are required for compliance with the General Order of Waste Discharge Requirements. But, are you certain you are taking samples properly to get the most accurate data thereby ensuring that your Nutrient Budget is a functional working document? Your sampling and analysis plan lays out exactly how you will take your samples. As you progress through corn silage harvest, here are some points to remember:

1. Your Sampling and Analysis Plan is a document that lays out how you will be gathering the information to fine tune your nutrient applications- use it!
2. Percent moisture is required for all forage samples. If percent moisture is incorrect because representative samples were not taken, the total dry matter harvested will be wrong, and the total nutrients harvested will reflect this error. Moisture varies greatly within a single field. Use sub-sampling as explained in the forage sampling protocol to obtain a representative sample.
3. Monitoring requirements have changed since last year. Harvests need to be quantified in tons; cubic yards are no longer acceptable. Required lab analyses now include fixed solids (ash), total phosphorus, and total potassium (total nitrogen analysis remains the same). Be sure your lab is analyzing for the right elements.

To get the best crop and avoid unwanted regulatory attention, it is in your best interest to get good, representative samples now to fine tune your nutrient application timing and quantity. Using good information to grow a quality crop and avoid regulatory penalties is money in your pocket.