Section 140. Required nutrient management plan procedures

A. Nutrient application.

1. A certified nutrient management planner shall include, in each plan, nutrient application practices for each field in the plan. The nutrient application rates shall be calculated for nitrogen (N), phosphate (P₂O₅), and potash (K₂O). Individual field recommendations shall be made after considering nutrients contained in fertilizers, manure, biosolids, industrial wastes, legumes in the crop rotation, crop residues, residual nutrients, and all other sources of nutrients. Individual fields may be grouped together if similar soil productivity levels, soil fertility levels, and environmentally sensitive site features exist.

2. Nutrient application rates.

a. Determination of crop nutrient needs shall be consistent with tables and procedures contained in Virginia Nutrient Management Standards and Criteria, revised July 2014, and the Commercial Vegetable Production Recommendations, 2005 (Virginia Cooperative Extension Publication 456-420), and shall be based on soil test results for P₂O₅ and K₂O.

b. Nitrogen applications rates in nutrient management plans shall not exceed crop nutrient needs in subdivision 2 a of this subsection.

c. Phosphorus application rates shall be managed to minimize adverse water quality impacts consistent with subdivisions 2 c (1) through (5) of this subsection.

(1) Phosphorus applications from inorganic nutrient sources shall not exceed crop nutrient needs over the crop rotation based on a soil test.

(2) Phosphorus applications shall not be included in nutrient management plans developed after December 31, 2005, for soils exceeding 65% phosphorus saturation levels as listed in Virginia Nutrient Management Standards and Criteria, revised July 2014, regardless of the outcome of other procedures specified in this subsection except as allowed in subdivision 2 c (4) of this subsection.

(3) Whenever possible, phosphorus applications from organic nutrient sources should not exceed crop needs based on a soil test over the duration of the crop rotation. If this is not possible, maximum phosphorus application rates and phosphorus control practices contained in nutrient management plans shall be consistent with the phosphorus management provisions contained in Virginia Nutrient Management Standards and Criteria, revised July 2014, except as allowed in subdivision 2 c (4) of this subsection.

(4) Fields controlled by existing operations that receive phosphorus applications only from on-farm or on-site generated liquid dairy manure, liquid swine manure, or liquid sewage sludge shall be limited to a maximum of crop removal amounts of applied phosphorus until December 31, 2010, if the field exceeds 65% phosphorus saturation levels or has a phosphorus index rating that exceeds 100. New operations that begin production after December 31, 2005, or operations that expand after December 31, 2005, by increasing the total phosphorus generated in liquid dairy manure, liquid swine manure or liquid sewage sludge by more than 10% shall not be considered existing operations.

(5) A single phosphorus application may be recommended to address multiple crops in the crop rotation identified within the timeframe covered by the nutrient management plan consistent with 4VAC50-85-140 D 1 if the single application does not exceed the sum of the appropriate application rates for individual crops as determined by subdivisions 2 c (1) through (3) of this subsection.

d. Recommended application rates for secondary nutrients and micronutrients should be at agronomically or economically justifiable levels for expected crop production. Potassium applications sufficient to meet crop nutrient needs shall be included in nutrient management plans for all fields consistent with recommendations contained in Virginia Nutrient Management Standards and Criteria, revised July 2014.

e. Expected crop yield shall be determined from any of the following methods on a given field:

(1) Soil productivity group expected crop yields based on and consistent with soil productivity information contained in Virginia Nutrient Management Standards and Criteria, revised July 2014;

(2) The farmer's past experience with crop yields in specific fields may be used to make reasonable adjustments to expected crop yields in subdivision 2 e (1) of this subsection in lieu of verifiable yield records provided the upward adjustments impact no more than 20% of the acreage of any crop on a particular farm; or

(3) Verifiable past crop yields are utilized to determined expected crop yield. The calculation of expected crop yield shall be an average of the three highest yielding years taken from the last five years the particular crop was grown in the specific field.

f. Representative soil analysis results for fields shall be determined by using standard soil sampling and analysis methods according to Methods of Soil Analysis, Part 3, Chemical Methods, 1996, utilizing the Mehlich I extraction procedure for phosphorus or other methods and laboratories approved by the department and correlated to Mehlich I and utilizing correlation procedures contained in Virginia Nutrient Management Standards and Criteria, revised July 2014. Soil analysis results shall be dated no more than three years prior to the beginning date of the nutrient management plan. A single composite soil sample should represent an area up to approximately 20 acres. Fields such as those common to strip cropping may be combined when soils, previous cropping history, and soil fertility are similar. Representative soil sample cores shall be obtained from the soil surface to a depth of four inches (0-4") for fields that have not been tilled within the past three years, and from the soil surface to a depth of six inches (0-6") for fields that are tilled or have been tilled within the past three years. Soil sampling of fields based on subfield grids or management zones may be utilized.

g. For existing operations, the most recent organic nutrient source analysis results or an average of past nutrient analysis results for the specific operation within the last three-year period shall be used to determine the nutrient content of organic nutrient sources. Manure analyses shall include percent moisture, total nitrogen or total Kjeldahl nitrogen, ammonium nitrogen, total phosphorus, and total potassium determined using laboratory methods consistent with Recommended Methods of Manure Analysis, publication A3769, University of Wisconsin, 2003, or other methods approved by the department. For plans on new animal waste facilities, average analyses published in Virginia Nutrient Management Standards and Criteria, revised July 2014, should be utilized unless proposed manure storage and treatment conditions warrant the use of alternative data. Plant available nutrient content shall be determined using the mineralization rates and availability coefficients found in Virginia Nutrient Management Standards and Criteria, revised July 2014, for different forms and sources of organic nutrients. Mineralization of organic nutrients from previous applications shall be accounted for in the plan.

h. The expected nitrogen contributions from legumes shall be credited when determining nutrient application rates at levels listed in Virginia Nutrient Management Standards and Criteria, revised July 2014.

3. Soil pH influences nutrient availability and crop nutrient utilization and should be adjusted to the level suited for the crop. Nutrient management plans shall contain lime recommendations to adjust soil pH to a level within the appropriate agronomic range for the existing crop or crop(s) to be grown. Recommendations shall address lime application if soil pH is below the optimal range. Nutrient management planners shall not recommend the application of lime, lime-amended materials, or nutrient sources that are expected to raise the soil pH to a level that exceeds the appropriate agronomic range for the growing crop or crop(s) to be grown based on recommendations contained in Virginia Nutrient Management Standards and Criteria, revised July 2014.

4. Nutrient application timing.

a. Timing recommendations for nutrient sources containing nitrogen shall be as close to plant nutrient uptake periods as reasonably possible. A certified nutrient management planner shall utilize procedures contained in Virginia Nutrient Management Standards and Criteria, revised July 2014, to determine the timing of nutrient applications. To reduce the potential for nutrient leaching or runoff, a certified nutrient management planner shall recommend applications of nitrogen-containing materials only to sites where an actively growing crop is in place at the time of application or where a timely planted crop will be established within 30 days of the planned nutrient application, except as specified in subdivisions 4 b through e of this subsection. If such nutrient applications are made to fall-seeded crops such as small grain, the crop planted shall be capable of germination and significant growth before the onset of winter so the crop is able to take up the available applied nitrogen.

b. Organic nutrient source applications may be applied at differing times than specified in subdivision 4 a of this subsection in order to manage storage constraints in accordance with the following conditions:

(1) Applications of organic nutrient sources shall be within 60 days of planting a spring seeded crop to sites that are not environmentally sensitive sites as identified in 4VAC50-85-10 or the Virginia Nutrient Management Standards and Criteria, revised July 2014, except as specified in subdivision 4 b (2) of this subsection. Such nutrient applications shall not exceed allowable application rates of the spring seeded crop;

(2) Applications shall be within 90 days of planting a spring seeded crop to sites that meet all of the following requirements:

(a) Are not environmentally sensitive sites as identified in 4VAC50-85-10 or the Virginia Nutrient Management Standards and Criteria, revised July 2014;

(b) Have slopes of less than 7.0% throughout the application area unless: (i) at least 60% uniformly distributed crop residue cover exists following application or (ii) the application and any associated tillage is in conformance with an existing and implemented soil conservation plan meeting NRCS requirements for the site; and

(c) The organic sources being applied are one of the following: semi-solid beef manure, semi-solid dairy manure with sawdust bedding or straw bedding, dewatered anaerobically digested sewage sludge, or dewatered lime stabilized sewage sludge. Such nutrient applications shall not exceed allowable application rates of the spring planted crop;

(3) Applications of organic nutrient sources may occur prior to the times specified in subdivisions 4 b (1) and (2) of this subsection on:

(a) Sites that are not environmentally sensitive sites if all of the following requirements are met: (i) a trap crop exists that has reached a Zadoks growth stage of 23 or greater having a uniform stand throughout the site area of at least 20 plants per square foot; (ii) the trap crop shall be allowed to continue growing on the entire site until within two weeks of the spring crop planting date; (iii) all such nitrogen applications of organic nutrient sources to trap crops shall not exceed the crop nutrient needs of the upcoming spring planted crop subtracting at least 30 pounds per acre of nitrogen to be reserved for use as a banded starter fertilizer at the time of spring planting; and (iv) the rate of organic nutrient source applied does not smother the crop.

(b) Environmentally sensitive sites as identified in 4VAC50-85-10 or the Virginia Nutrient Management Standards and Criteria, revised July 2014, in addition to those criteria outlined in subdivision 4 b (3) (a) of this subsection, such applications to a trap crop must be within 60 days of planting a spring planted crop.

c. The nutrient timing requirements of subdivisions 4 a and b of this subsection for application of sewage sludge to nonenvironmentally sensitive sites in nutrient management plans shall not be effective until January 1, 2009. The delayed implementation time is provided to allow for the development of adequate winter storage capacity, landfilling, or alternative uses. All applications of sewage sludge to environmentally sensitive sites in nutrient management plans will fully comply with the requirements of subdivisions 4 a and b of this subsection by January 11, 2006.

d. Composted organic nutrient sources having a final carbon to nitrogen ratio of 20:1 or greater are exempt from requirements of subdivisions 4 a and b of this subsection if analyzed for carbon to nitrogen ratio at the conclusion of the composting process and results are obtained prior to land application. The planner shall recommend soil nitrate testing to determine nitrogen application rates during the growing season following the application of composted organic nutrient sources.

e. The nutrient management planner shall recommend split application of inorganic nitrogen fertilizers as starter or broadcast and sidedressing or top dressing in row crops and small grains consistent with procedures contained in Virginia Nutrient Management Standards and Criteria, revised July 2014, on environmentally sensitive sites as identified in 4VAC50-85-10. Split applications of inorganic nitrogen fertilizers and irrigation scheduling shall be recommended for crops to receive irrigation. The use of a pre-sidedress nitrogen test (PSNT) can help to determine nitrogen needs during the growing period. In lieu of split applications, the planner may recommend the application of the total nitrogen requirement for spring-planted row crops within one week prior to planting if at least 50% of the plant available nitrogen requirement of the crop is supplied with slowly available nitrogen sources.

f. Nutrient management plans shall include a statement indicating that applications of inorganic nutrient sources, liquid manure, liquid sewage sludge, or liquid industrial waste are not to occur on frozen or snow-covered ground. When ground is frozen, dry or semi-solid manures, dewatered sludges, or dewatered industrial wastes may only be applied if the field has: (i) slopes not greater than 6.0%; (ii) 60% uniform ground cover from crop residue or an existing actively growing crop such as a small grain or fescue with exposed plant height of three inches or more; (iii) a minimum of a 200-foot vegetated or adequate crop residue buffer between the application area and all surface water courses; and (iv) soils characterized by USDA as "well drained."

5. Application method for nutrients.

a. The application of nitrogen containing materials shall be managed to minimize runoff, leaching, and volatilization losses.

b. Applications of liquid manures or sludges utilizing irrigation shall not be recommended to be applied at hydraulic rates above those contained in Virginia Nutrient Management Standards and Criteria, revised July 2014.

c. Plans shall not recommend liquid manure or sludge application rates utilizing nonirrigation liquid spreading equipment which exceed 14,000 gallons per acre (approximately one-half (0.5) inch) per application. The amount of liquid manure or sludge application in plans will not exceed the hydraulic loading capacity of the soil at the time of each application. If a subsequent pass across a field is necessary to achieve the desired application rate, the plan will allow for sufficient drying time.

d. Where possible, the planner should recommend that biosolids, industrial wastes and manures be incorporated or injected in the crop root zone in order to reduce losses of nitrogen to the atmosphere and to increase the plant available nitrogen to phosphorus ratio of these nutrient sources relative to crop nutrient needs. Lime stabilized biosolids should not be injected due to the creation of a localized band of high soil pH unless subsequent practices are utilized, such as disking, in order to adequately mix the soil.

e. The planner shall recommend setbacks around wells, springs, surface waters, sinkholes, and rock outcrops where manure, biosolids, or industrial waste should not be applied. Such setbacks recommended shall be consistent with criteria contained in Virginia Nutrient Management Standards and Criteria, revised July 2014, unless alternative setbacks or buffers are specified in regulations or permits pertaining to the site. For sites impacted by other regulations or permits, the planner shall include the setbacks and buffers specified in regulations promulgated under § 62.1-44.19:3 of the Code of Virginia for sewage sludge, § 62.1-44.17:1 of the Code of Virginia for animal waste, § 62.1-44.17:1.1 of the Code of Virginia for poultry waste, and Article 2.5 (§ 62.1-44.15:67 et seq.) of Chapter 3.1 of Title 62.1 of the Code of Virginia for sites in Chesapeake Bay Preservation areas, and permits for industrial waste land application. The land area within setback and buffer areas shall be deducted from field acreage to determine usable field acreage for nutrient application in nutrient management plans.

B. Manure production and utilization.

1. The planner shall estimate the annual manure quantity produced on each farm utilizing tables and forms contained in Virginia Nutrient Management Standards and Criteria, revised July 2014, or from actual farm records of manure pumped or hauled during a representative 12-month period.

2. The nutrient management plan shall state the total amount of manure produced and the amount that can be used on the farm, utilizing the information and methods provided in the Virginia Nutrient Management Standards and Criteria, revised July 2014. The plan shall discuss any excess manure and shall provide recommendations concerning options for the proper use of such excess manure.

C. Plans shall identify and address the protection from nutrient pollution of environmentally sensitive sites.

D. Plan maintenance and revisions.

1. A site-specific nutrient management plan developed in accordance with all requirements of these regulations, including specified crops or crop rotations, shall provide information on soil fertility and seasonal application of required nutrients for one to five years of crop production. Plans developed for a period of time greater than three years and up to five years shall be limited to sites in permanent pasture or continuous hay or that are golf courses.

2. The plan shall state a need for immediate modification if (i) animal numbers are to increase above the level specified in the plan; (ii) animal types including intended market weights are to be changed; (iii) additional imported manure, biosolids, or industrial waste that was not identified in the existing plan is to be applied to fields under the control of the operator; or (iv) available land area for the utilization of manure decreases below the level necessary to utilize manure in the plan. The plan shall also state a need for modification prior to subsequent nutrient applications if cropping systems, rotations, or fields are changed and phosphorus will be applied at levels greater than crop nutrient needs based on soil analysis as determined from procedures in Virginia Nutrient Management Standards and Criteria, revised July 2014.

3. Adjustments to manure production and application should be made if there are increases in animal numbers or changes in how animal waste is stored or applied, or when there are changes in nutrient content of manure resulting from changing feed rations, animal types, or new sampling and analysis for nutrient content and application rate calculations.

4. Soil analysis shall be recommended for each field at least once every three years to determine the soil fertility and pH, and to update the nutrient management plan.

5. Manure analysis shall be recommended before field application until a baseline nutrient content is established for the specific manure type on the corresponding farm operation. After a baseline nutrient content is established, a manure analysis shall be recommended at least once every three years for dry or semisolid manures, and at least once every year for liquid manures.

6. Modified top dressing or sidedressing application rates of nitrogen may be recommended if a pre-sidedress nitrogen test (PSNT) administered during the growing season indicates different levels of nitrogen than planning time calculations if the use of the PSNT and interpretation of the test results are consistent with Virginia Nutrient Management Standards and Criteria, revised July 2014.

Historical Notes

Former 4VAC5-15-150, derived from VR 217-03-00 § 15, eff. January 24, 1996; amended, Volume 22, Issue 07, eff. January 11, 2006; amended and renumbered, Virginia Register Volume 30, Issue 11, eff. February 26, 2014; amended, Virginia Register Volume 31, Issue 03, eff. November 20, 2014.

Statutory Authority

§ 10.1-104.2 of the Code of Virginia.