# Presentation: 515319

## Nutrient Management Tools:The Yardstick in Wisconsin

***Kevin Erb***
***UW-Extension ***
***Environmental Resources Center***

## Farmer View of Site-Specific Future Manure Regulations

**Farmer View of Site-Specific Future Manure Regulations**

## Environmentalist’s view of how farmersmanage manure.

**Environmentalist’s view ****of how farmers****manage manure.**

**Notes:**
Is this a public relations problem???

Yes, there IS a manure spreader buried under this pile of manure.

The tractor would not start and the farmer kept cleaning the barn.

When did he move the tractor?? When the manure finally hit the seat.

## Slide 4

## The Yardstick

**The Yardstick is a Mass Balance Tool designed to help farmers identify the ****sources**** of nutrients entering and leaving the farm, allowing them to make more informed decisions on how to deal with nutrient loading.**

## What is a Mass Balance?

** ****Identifying all sources of nutrients entering and leaving the farm**
**Inputs: Feed, Fertilizer, purchased animals**
**Outputs: Milk, Meat, Crops sold.**
**Environmental sources: Legumes, Rain**
**Environmental Losses: Leaching**
**Goal is to be near zero.**

## Dutch Yardstick

-  **Developed in the Netherlands in ‘80’s.**
-  **Used as an Environmental Taxation Tool**
** ****Import too much: Tax penalty**
** ****Below balance: Tax credit**

## Yardstick in the US

** ****Imported in mid 90’s by IATP (Institute for Ag Trade and Food Policy, Minneapolis)**
**Adapted for use in the US by WI, MN**
** ****US version significantly easier to use**

## Yardstick Usage

** ****Four main projects in Midwest:**
** ****Blue Earth Basin (MN)**
** ****Apple-Ashwaubenon (WI)***
** ****Mendota Watershed (WI)**
** ****Central Nebraska**
*** Apple-Ashwaubenon was my MS Thesis project**

## Yardstick - US

- Mark Muller, Senior Associate
- Institute for Agriculture and Trade Policy
- 2105 First Avenue South
- Minneapolis, Minnesota 55404
- phone: (612) 870-3420; fax: (612) 870-4846email: _[mmuller@iatp.org](mailto:mmuller@iatp.org)__ _

## Yardstick - US

**Excel Spreadsheet and paper version available**
**Some aspects are being incorporated into SNAP PLUS, covered in the next session**

## Focus

**Identify amount and sources of nutrients entering and leaving the farm**
**Whole farm target, but animal enterprises can be isolated with some modifications to data collection**

## Focus

**Collects N, P, K data**
**Micronutrients (Sulfur, Selenium) can be added with modifications**
**Potassium data has been the key to getting dairy farmers to use Yardstick results**

## Slide 15

## Usability

## Usability

**Targeted to livestock farms, valid for cash grain.**
**Paper version: If you passed 4****th**** grade math, you can use the yardstick**
**Electronic Version: Excel 95 or above (not MS Works Spreadsheet)**

## Usability

**Easy enough for  a farmer to use, but best method is to have someone trained for data collection and results interpretation**
**Can be used on any farm *****where the farmer has kept decent records*****.**
**Some CCA’s have explored using the tool, none are.**

## Usability

- In-tool tables for common feed/crop nutrient values.

| Table 2 - Nutrient Composition of Common Crops and Forages* |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- |
| CROP | CP % | N % |   | P % |   |   | K % |
| Soybeans1 | 42.80% | 6.85% |  | 0.65% |  |   | 1.82% |
| Corn1 | 7.90% | 1.26% |  | 0.25% |  |   | 0.33% |
| Oats1 | 11.00% | 1.76% |   | 0.35% |   |   | 0.37% |
| Alfalfa hay2 | 14.06% | 2.25% |  | 0.20% |  |   | 1.85% |
| Timothy hay2 | 7.50% | 1.20% |  | 0.20% |  |   | 1.60% |
| Red clover hay3 | 12.50% | 2.00% |  | 0.22% |  |   | 1.66% |
| Smooth bromegrass4 | 10.63% | 1.70% |  | 0.29% |  |   | 2.10% |
| Corn Silage5 | 8.38% | 1.34% |  | 0.21% |  |   | 1.25% |
| Sorghum silage | 12.50% | 2.00% |  | 0.35% |  |   | 2.40% |
| Wheat straw | 4.06% | 0.65% |  | 0.05% |  |   | 0.95% |
| Barley straw | 4.69% | 0.75% |  | 0.10% |  |   | 1.25% |
| Oats straw | 3.75% | 0.60% |  | 0.15% |  |   | 1.65% |
| Sugarbeets6, beet | 1.31% | 0.21% |   | 0.01% |   |   | 0.35% |
|  |  |  |  |  |  |  |  |

## Expandability

**Most WI users have added a linked spreadsheet to deal with purchased feeds**

## Outputs

_**Basic Level:**_** N, P, K surplus (deficit) on a per acre basis.**
_**Advanced:**_** Ability to modify operation to determine nutrient impacts**
**How many acres do I need to add to be in a P balance? **
**What happens if I add 50 sows?**
**If I buy hay instead of growing it, what happens to my overall environmental impact?**

## Outputs

_**Regulatory:**_**  A mass balance at some level is required by some WPDES large livestock permits currently**
**Too many variables to be used in a strict regulatory sense (poor year = low yields = more feed bought)**
**Long term trend is more important**

## Apple-Ashwaubenon 1997-1998

** ****17 farms**
** ****13 dairies from 50 to 500 hd**
** ****4 cash grain operations**
** ****Follow-up study (2001) now underway by UW Madison****.**

## Nutrient SurplusApple-Ashwaubenon Study

**Lb/Acre**

**Notes:**
When determining manure nutrient credits, be certain you are dealing with “the available” nutrient content of manure. Manure analysis results are often reported as total and available nutrient content. Not all the nitrogen (or P and K) contained in manure is available for crop uptake, as shown here.

Roughly 60 to 70% of the N in manure is assumed to NOT be available to crops.

## Sources of Nutrients

## Slide 28

## CP:P Ratios of various protein sources

|  | Crude Protein | Phos | Ratio |
| --- | --- | --- | --- |
| Cottonseed | 46 | 1.1 | 41.8 |
| 44% SBM | 44 | 0.6 | 73.3 |
| Corn Gluten | 60 | 0.7 | 85.7 |

## 80% of the excess Phosphorus could be eliminated by reducing the P in the dairy ration from 0.52 to 0.38%.

## Limitations

_**Poor farm records**_
**Over 17 farms, the heifer:bull calf ratio was 7:1**
**Tax records are not tonnage records**
**Most records came not from the farm, but from the supplier (feed mill, dealer, etc)**

## Limitations

_**Time**_
**Depending on the farm’s records, completing the yardstick took between 1⁄2 and 22 hours to complete.**
**Having an experienced person who knows what records to look for (and where to find them) pays big dividends.**

## Nutrient Loading Changes

**Goal is to open farmers eyes and allow them to see where changes can be made**
**Main impacts are in how livestock are fed**

## Yardstick vs. a Nutrient Management Plan

**Scale****: NMP is field level, yardstick is farm.**
**Results:**** Just because a farm is in balance does not mean that nutrients are being applied in the right places at the right rates.**

## Future Vision

**Multi-year field scale mass balance will be a part of the SNAP PLUS software.**
**Watershed Carrying Capacity studies?**

## Slide 36

## Thanks for your time !

***Kevin Erb***
***UWEX ERC***
***kevin.erb@ces.uwex.edu***

## Additional Slides if we have time or need to discuss further

## Study Goals

** ****Do large farms have a greater potential to pollute (P) than small farms?**
**Where is our P coming from -- -- and will Nutrient Management solve the problem?**
**Mass balance of different farm sizes best way to answer the question.**

## Slide 40

|  | Farm Years | N Mean (lbs/acre) | P Mean (lbs/acre) | K Mean (lbs/acre) |
| --- | --- | --- | --- | --- |
| cash grain farms |  8 | -9 |  3 |  23 |
| all dairy farms | 26 |  87 | 15 |  80 |
| Lb/cow/yr: all dairy farms | 26 | 124# /cow | 21# /cow | 106# /cow |

## Nitrogen imports by source

## Nitrogen movement off-farm

## Slide 43

## Slide 44

## Slide 45

## CP and Phosphorus vary between protein supplement sources.

## Slide 47

## Soil Test Phosphorus Variability from a Wisconsin Dairy Farm

**Notes:**
This graphic illustrates the variability of field soil nutrient levels from a Wisconsin dairy farm. This pattern is typical of Wisconsin livestock farms.

Note that soil test P values vary from very low to excessively high across the 12 fields on this dairy farm.

The source of this variation can be attributed to manure distribution on the farm. Field 10 is probably next to the barn (hence, a long history of manure applications resulting in  elevated soil test P levels) while field 7 is distant from the barn.

Parameters on the graph:
The green bar is the optimum soil test range for P of the most demanding crop (usually alfalfa) in the rotation.

## Dietary P Management - On-Farm Phosphorus Balance  

**Notes:**
On-farm P cycling and P balancing are illustrated with this graphic.

Inputs to the farming system include: feed, fertilizers, mineral and protein supplements, etc.

Outputs from the farming system include: exported milk, meat, and crop products.

A consequence of P inputs exceeding P outputs is the net importation (or positive balance) and storage of P on the farm. The result will be a build-up of soil test P values over time. The latter, in turn, increases the potential for P loss to lakes and streams if runoff and erosion occur on the farm. 

One strategy for balancing P is to decrease dietary P inputs to recommended levels.

## Dietary P Management - Why is P Fed at Excessive Levels?   

- Reproductive Efficiency
- Common belief that high P diets improve animal reproductive efficiency.
- Research does not support this theory.
- National Research Council recommends dietary-P levels of 0.32 to 0.38% - depending on milk production.
- Over-feeding statistics:
- Survey of  Wisconsin dairy farms found 85% fed P in excess of NRC recs and over half were fed in excess of 0.38% P.

**Notes:**
Many dairy herds are fed dietary P at levels that exceed U.S. National Research Council (NRC) recommendations – which range between 0.32 and 0.38% P, depending on milk production. 

To minimize perceived risks of P deficiency, many dairy herds are fed dietary P at levels that exceed NRC recommendations. The common practice of overfeeding P to animals – particularly dairy cattle - stems from a widely held belief that high P diets improve animal reproductive performance. While it is true that P deficiencies can lower the reproductive fertility of dairy cattle, reviews of published research trails show little indication that feeding excess P enhances animal fertility. Most studies show that problems in dairy cows don't begin to show up until dietary P levels fall below 0.3%.

It is common to see dietary P levels between 0.5 and 0.6% for high producing herds. Such levels of dietary P are excessive and can be substantially reduced without sacrificing milk production and quality. A survey of Wisconsin dairy producers (Powell et al., 2001) found the reported P content of animal diets ranged from 0.23 to 0.85% P with the average being 0.40%. Approximately 85% of the surveyed dairy farms fed in excess of NRC requirements and over half of all cows were being fed P in excess of 0.38%.  

## Dietary P Management – NRC Feed Recommendations  

**National Research Council (NRC) Feed-P Recommendations**
** **
**	****	****Milk Production****	****  Dietary P Level**
**	****	****     ****(lbs/day)****	****	****	**** ****(%)**
**	****	****         ****55****	****	****	****	****0.32**
**	****	****         ****77****	****	****	****	****0.35**
**	****	****         ****99****	****	****	****	****0.36**
**	****	****       ****120****	****	****	****	****0.38 **
- Adapted from *Nutrient Requirements for Dairy Cattle*, Seventh Revised Edition,
- National Academy Press Washington, D.C., January 2001

**Notes:**
The U.S. National Research Council recommends that the typical dairy cow diet contain between 0.32 and 0.38% P, depending on milk production. 

## Dietary P Management - Why is P Fed at Excessive Levels?  

- Reproductive Efficiency
- Affordable Protein Sources
- Undegradable Protein Sources
- Animal protein sources
- Heat-treated sources
- Other Protein Sources
- Soybean meal
- Distiller’s dried grain
- Protein sources provide a _very_ high level of dietary-P.

**Notes:**
A second reason for P being fed at excessive levels is that the P levels of purchased dietary protein supplements is high. Dairy producers feed “by-pass” protein sources to livestock in order to get higher amounts of protein through the rumen (undegraded intake protein - UIP). Many of these protein sources provide significant amounts of P as well as UIP resulting in the enrichment of manure with P.

Purchased P in the form of mineral supplements can often be eliminated on farms feeding protein-source products like meat and bone meal, corn gluten and other by-products.

## Dietary P Management - Why is P Fed at Excessive Levels?  

- Reproductive Efficiency
- Affordable Protein Sources
- Affordable Nutrient Sources
- Energy & Fiber Sources
- Whole soybean, tallow, cottonseed
- Nutrient sources can also provide a _very_ high level of dietary-P.

**Notes:**
Feed supplements other than those used as protein sources can also increase the dietary intake of P and the resulting P content of manure. Feed supplements used to provide energy and fiber to livestock commonly deliver P as well. Dietary rations that are formulated using feed by-products should be closely evaluated for P levels. In some instances, producers may want to change their by-product purchases in order to better fit the goals of their nutrient management plans. 

## Dietary P Management - Why is P Fed at Excessive Levels?  

- Reproductive Efficiency
- Affordable Protein Sources
- Affordable Nutrient Sources
- Cattle are not harmed by over-feeding P at commonly found levels, _**BUT**_, manure-P levels increase with elevated levels of P intake.

## Dietary P Management – Implications of a High-P Diet  

** ****Dietary-P****	****  Manure-P****	****Spreadable Acres* ****	****Acres Needed***
**	****  ****(%)****	****	****(lbs/cow/year)****	****    (acres/cow/year)****	****	**** (100 cow dairy)****	**
**	****0.35****	****     ****	****       42****	****	****	****1.6****	****	****       160**
**	****0.38****	****     ****	****       47****	****	****	****1.8****	****	****       180**
**	****0.48****	****	****       65****	****	****	****2.4****	****	****       240**
**	****0.55****	****      ****	****       78****	****	****	****2.9****	****	****       290**
***Farmers may need to manage dietary P intake in order to reduce manure-P.***
***   *************	******Acres required to meet a P-based nutrient management plan. Manure application rates restricted to crop-P removal from an alfalfa, corn, soybean cropping system.  ***

**Notes:**
This table illustrates the increase in manure-P content (bypass-P) with increasing dietary intake of P.

The table also illustrates that the excess supplementation of dietary-P to dairy cattle can dramatically increase the land required for manure application if a producer is required to meet P-based manure application criteria.  One P-based strategy proposed for Wisconsin is the restriction of manure application rates to crop-P removal. In a Wisconsin farm scenario described by Powell and Peters (2000), approximately 1.8 acres of a mixed alfalfa, corn, and soybean cropping system is required to utilize the manure-P excreted from each lactating cow fed at 0.38% dietary P. Raising dietary P from 0.38 to 0.48% increases the cropland area needed per cow by 44%. The trend continues with increasing dietary P levels. The substantial range in the amount of spreadable acres needed to meet a P-based manure application strategy reflects the large impact dietary P levels can have on land requirements for manure spreading. 

Reference:  Powell, J.M. and J.B. Peters. 2000. Phosphorus feeding strategies for dairy: Effects on manure P and P cycles. In Proc. 2000 Area Fertilizer Dealer Update Meetings. No. 3-2000, Nov., 2000. Univ. Wis. Dept of Soil Sci. Madison, WI.

Speaker:
Much more information on the role of dairy diets in nutrient management planning can be found in the curriculum “ Dairy Whole-Farm Nutrient Management – The Diet Connection.”  This curriculum is available from the NPM Program. Call 608-265-23789 or e-mail lnadams@widc.edu to request a copy.

## Phosphorus Exports

## Slide 57

## Slide 58

## Slide 59

## Slide 60

## Conclusions

** ****Acres and cow numbers**
** ****DO NOT affect per acre phosphorus loading.**
** ****Increase per acre N and K loading.**
**Phosphorus problem CAN NOT be solved by just looking at the fertilizer sources.**

## Conclusions

** ****Implementing the following eliminated surplus**
** ****Reduce feed P from 0.52 to 0.38%**
** ****Reduce % P in starter fertilizer **(9-23-30  9-15-30)
** ****Minor change in manure rates on some fields.**