This document is an instruction guide for creating and implementing a nutrient management plan (NMP) on certified or transitioning organic lands. An NMP for organically managed lands describes the amount, source, placement, form, and timing of the application of nutrients and soil amendments, generally by field, to meet crop nutrient needs while protecting water quality, improving soil health, and utilizing manure and other organically acceptable byproducts as nutrient sources.
Nutrient Management Plan (590) for
Organic Systems
Western State Implementation Guide
March 2014
National Center for
Appropriate Technology (NCAT)
www.ncat.org
Oregon Tilth
www.tilth.org
1
Contents
Purpose and Objectives……………………………………………. 3
Relevant National Organic Standards……………………. 4
Section 1.
Determining Crop Need for
Nitrogen, Phosphorus, and Potassium…………………… 5
Section 2.
Developing Nutrient Credits……………………………………. 6
Section 3.
Determining Nutrient Application Rates………………. 10
Section 4.
Evaluating Risk of Leaching and Runoff……………….. 12
Section 5.
Calculating Nutrient Application Rates
Based on Risk Analysis…………………………………………….. 13
Appendix A.
Tables…………………………………………………………………………. 14
Appendix B.
Conversion Tables…………………………………………………….20
Appendix C.
References to NRCS Publications
and Other Resources………………………………………………..22
Figure 2. Six-foot-tall fava bean cover crop, Fong Farms,
Woodland, California 2006.
Funded by
a grant from
Western
Sustainable
Agriculture
Research and
Education
(WSARE).
Appendix D.
Implementation Requirement Worksheet…………… 26
Copyright © NCAT and Oregon Tilth 2014
www.ncat.org
www.tilth.org
ACKNOWLEDGMENTS
Authors Rex Dufour (National Center for Appropriate Technology), Sarah Brown (Oregon Tilth), and
Denise Troxell (NRCS)
Contributors and Reviewers Carrie Sendak (Oregon Tilth), Denise Troxell (OR-NRCS), Nick Andrews (Oregon State University), Giulio Ferruzzi (NRCS), Ben Bowell (Oregon Tilth), Jennifer Miller (Northwest Center
for Alternatives to Pesticides), Rich Fasching (NRCS), Dennis Chessman (CA-NRCS)
We thank Dan Sullivan, Extension Soil Scientist, Oregon State University for assistance in presenting methods
for estimating plant-available N release from organic inputs.
Editing and layout Karen Van Epen (NCAT), Robyn Metzger (NCAT)
All photos Rex Dufour (NCAT) unless other wise noted.
Figure 1. (On front cover) A farmer evaluates soil organic matter. Photo: David Lamm (NRCS)
2
Nutrient Management Plan (590) for Organic Systems
Implementation Guide
Purpose and Objectives
This document is an instruction guide
for creating and implementing a
nutrient management plan (NMP)
on certified or transitioning organic
lands.
An NMP for organically managed
lands describes the amount, source,
placement, form, and timing of the
application of nutrients and soil
amendments, generally by field, to
meet crop nutrient needs while
protecting water quality, improving
soil health, and utilizing manure
and other organically acceptable
byproducts as nutrient sources.
Developing an NMP entails:
Figure 3. Mowing vetch cover crop prior to transplant of processing tomatoes.
1) Determining a crop’s need for
nitrogen, phosphorus, potassium, and other
nutrients as appropriate
2) Crediting all significant sources of nutrients
in the system such as the nitrogen contribution
of cover crops, the mineralization of nitrogen
based on input history (previous years’ manure/
organic byproducts applications), and any nitrate
that may be contained in irrigation water
3) Determining the target nutrient application rate
(the difference between the crop need and the
nutrient credits)
4) Evaluating likelihood of nutrients moving past
the edge of a field or below the root zone (leaching
and runoff)
5) Calculating the appropriate rate of manure/ organic
product application based on this risk
Instructions
☞ This icon indicates you should fill in data on the Implementation Requirement Worksheet in
Appendix D, pages 26-30. Alternatively, you may use your state’s NM planning tool to enter the
crops grown.
☞ In the Field and Crop Information section, list the crops in the order they are grown. Check
the box for the current crop. Make additional copies of the form as needed.
3
Relevant National Organic Program (NOP) Regulations
National Organic Program (NOP) regulations section 205.203 should be referenced when assessing nutrient
management in organic systems. The entire NOP regulations, as well as lists of approved and prohibited materials
and other information can be found at the NOP website: www.ams.usda.gov/AMSv1.0/nop
Section 205.203 Soil Fertility and Crop Nutrient Management Practice Standard
(a) The producer must select and implement tillage
and cultivation practices that maintain or improve
the physical, chemical, and biological condition of soil
and minimize soil erosion.
(b) The producer must manage crop nutrients and
soil fertility through rotations, cover crops, and the
application of plant and animal materials.
(c) The producer must manage plant and animal
materials to maintain or improve soil organic matter
content in a manner that does not contribute to contamination of crops, soil, or water by plant nutrients,
pathogenic organisms, heavy metals, or residues of
prohibited substances. Animal and plant materials
include:
(1) Raw animal manure, which must be composted unless it is:
(i) Applied to land used for a crop not intended for human consumption;
(ii) Incorporated into the soil not less than 120
days prior to the harvest of a product whose
edible portion has direct contact with the soil
surface or soil particles; or
(iii) Incorporated into the soil not less than 90
days prior to the harvest of a product whose
edible portion does not have direct contact
with the soil surface or soil particles;
(2) Composted plant and animal materials produced through a process that:
(i) Established an initial C:N ratio of between
25:1 and 40:1; and
(ii) Maintained a temperature of between 131
°F and 170 °F for 3 days using an in-vessel or
static aerated pile system; or
(iii) Maintained a temperature of between
131 °F and 170 °F for 15 days using a windrow
composting system, during which period,
the materials must be turned a minimum of
five times.
(3) Uncomposted plant materials.
4
(d) A producer may manage crop nutrients and soil
fertility to maintain or improve soil organic matter
content in a manner that does not contribute to contamination of crops, soil, or water by plant nutrients,
pathogenic organisms, heavy metals, or residues of
prohibited substances by applying:
(1) A crop nutrient or soil amendment included on
the National List of synthetic substances allowed
for use in organic crop production;
(2) A mined substance of low solubility;
(3) A mined substance of high solubility: Provided,
That, the substance is used in compliance with the
conditions established on the National List of nonsynthetic materials prohibited for crop production;
(4) Ash obtained from the burning of a plant or
animal material, except as prohibited in paragraph
(e) of this section: Provided, That, the material
burned has not been treated or combined with a
prohibited substance or the ash is not included on
the National List of nonsynthetic substances prohibited for use in organic crop production; and
(5) A plant or animal material that has been chemically altered by a manufacturing process: Provided,
That, the material is included on the National List
of synthetic substances allowed for use in organic
crop production established in § 205.601.
(e) The producer must not use:
(1) Any fertilizer or composted plant and animal
material that contains a synthetic substance not included on the National List of synthetic substances
allowed for use in organic crop production;
(2) Sewage sludge (biosolids) as defined in 40 CFR
part 503; and
(3) Burning as a means of disposal for crop residues
produced on the operation: Except, That, burning
may be used to suppress the spread of disease or
to stimulate seed germination.
Section 1.
Determining Crop Need for Nitrogen, Phosphorus, and Potassium
This section outlines the process and resources to be used
to calculate the demand of a particular crop for N, P, K,
and other nutrients. Sources of information about crop
nutrient needs can be found in Appendix C, Section 1.
It is common for organic farms to grow many different
crops on relatively small acreages and for soil texture
to vary across the farm. In order to develop a practical
nutrient management plan for small plot acreages, it
may be helpful to work with the grower to develop
groupings of crops that have similar growth habits and
nutrient needs, and manage the grouping’s nutrient
needs as a single entity. Crop rotations are required in
organic systems. Growers should have a crop rotation
plan as part of their organic system plan.
Additional information to guide soil sampling strategies
and crop rotations on diverse organic vegetable farms
can be found in Appendix C, Section 1. Some possible
groupings include:
➢ Nitrogen Needs (Ideal): Low/Medium/High N.
See Table 1.
➢ Plant Family: For example, all solanaceous or all
brassica crops
➢ Timing: Early season, mid-season, and late
season plantings. Timing will impact nutrient
availability from soil N mineralization. Early
season crops will be unlikely to pull much from
the soil and should be fertilized accordingly.
➢ Crop Growth: Short-season crops, long-season crops
➢ Crop Type: Grains, legumes, vegetables, fruits
➢ Other: Growers also take other considerations into
account such as irrigation system layout, pest cycles,
and soil type.
Table 1. Nitrogen requirement of vegetable
crops based on seasonal nitrogen uptake
Low Total
Medium Total
N Need
N Need
<120 lb/acre <120-200 lb/acre
Baby greens
Carrot
Beans
Corn, Sweet
Cucumbers
Garlic
Radish
Lettuce
Spinach
Melons
Squashes
Onion
Peppers
Tomatoes
High Total
N Need
>200 lb/acre
Broccoli
Cabbage
Cauliflower
Celery
Potato
— Gaskell et al. 2006, Soil Fertility Management for
Organic Crops
Western States grow a great variety of specialty crops.
Your state cooperative extension office has horticulturalists
and agronomists who can point you in the right direction
for informational resources about the nutrient needs of
less commonly planted crops. Some specialty crops may
require higher amounts of particular micronutrients,
which if not present will limit quality and yields. Other
crops may be more sensitive to excess micronutrients, such
as citrus sensitivity to boron. If no University recommendations are available for a crop, an acceptable strategy is
to balance N, P and K applied with N, P and K expected
to be removed by the crop.
☞ Enter crop nutrient requirements and yields
under Recommended Nutrients to Meet Yield.
Resources for Nutrient Requirements of Crops
California Cooperative Extension:
www.ucanr.edu/sites/nm/Crop
Idaho Cooperative Extension and Idaho Nutrient
Management: www.extension.uidaho.edu/nutrient
Nevada Cooperative Extension: See Section IV of
eFotg, Nutrient Management 590 Job Sheet
NRCS Crop Nutrient Tool:
http://plants.usda.gov/npk/main
NRCS Agricultural Waste Management Field
Handbook provides data on N, P and K content of a
wide variety of crops.
ftp://ftp.wcc.nrcs.usda.gov/wntsc/AWM/handbook/
ch6.pdf
Oregon State University Fertilizer/Nutrient
Management Guidelines for Crops:
http://extension.oregonstate.edu/catalog/details.
php?sortnum=0134&name=Fertilizer+Guides&cat=
Agriculture
5
Section 2.
Developing Nutrient Credits
This section outlines some methods to calculate the
nutrient contributions of:
➣ Soil Organic Matter (SOM) N mineralization
➣ Cover crops
➣ Organic amendments such as manure, compost,
and some specialty fertilizers
The input history of a field is valuable, because many
sources of organic N continue to mineralize over several
years. As part of their organic recordkeeping requirements, organic farmers will have records of their soil
fertility inputs, as well as yield data, and these can help
to make a more comprehensive nutrient management
plan. Transitioning farmers may have no records if they
are early in their transition. Recent soil test information
will provide information about what is present in the
soil. Sources of information about organically acceptable
fertilizers can be found in Appendix A, Tables 4, 5, and 6.
Soil test results can come in either text or graphical formats. Discuss with the producer which format is preferred. University nutrient management guides provide
more accurate crop-specific sufficiency levels than general ranges. Refer to your state’s Conservation Practice Standard 590 for the required soil tests. A listing of
accredited (NAPT-PAP certified labs) soil testing labs
can be accessed at: www.naptprogram.org/pap/labs.
Tests of plant tissue, water and organic materials must
be conducted by labs that are certified by organizations
noted in the state’s 590 practice standard.
Soil Test Information and Resources
☞
Soil test and leaf test results taken at different times of
year provide valuable data for monitoring the performance
of nutrient management plans. This is especially useful
for refining N fertilizer rates. Pre-Side-dress Nitrate Tests
(PSNTs) can ensure a grower that N levels are sufficient
for the crop. PSNTs are generally done in the late spring
and allow the grower to respond to early spring weather
conditions that impact N mineralization. End-of-season
soil nitrate tests can determine whether N fertilizer rates
were higher than necessary. In most perennial crops, leaf
tests are used to determine crop nutrient status. These
naturally incorporate non-fertilizer nutrients taken up by
the crop.
Mineralization from “native” SOM is generally not
included in NRCS nutrient management plans because
land-grant university recommendations for N fertilizer
application rate assume typical soil N mineralization
already (under conventional management). However
under long-term management with consistently high
organic-N inputs, soil N mineralization may supply a
significant portion of crop N needs.
P and K should be managed by soil tests and attention
to P and K removal through harvest of crop biomass.
P and K fertilization decisions typically do not require
consideration of target yield for the crop. Crops grown
6
in soil with high P and K concentrations usually do not
respond to P and K fertilizers. When large amounts of
crop biomass are removed at harvest (i.e., alfalfa, or corn
silage) significant amounts of P and K are removed from
the soil. Other crops such as raspberries or blackberries
do not remove large amounts of P and K.
Enter soil test results under the Soil Test
Information section.
Nitrogen (N)
Nitrogen in organic systems is often tied up in organic
matter, and not in a form that is immediately available
to plants. Most organically acceptable sources of N have
lower N concentrations than chemical fertilizers, and
typically release less of their total N in the first cropping
season. In contrast, PAN for chemical fertilizers such as
urea, ammonium sulfate, and others, is 100%. That is,
the N is available to the plant shortly after application as
either nitrate (NO3 —this is the form most plants take
up N), or ammonium (NH4+). Possible sources of N for
organic systems include compost, manures, cover crops,
organic matter mineralization, organic approved fertilizers (fish meal, feather meal, etc.), and irrigation water.
In some locations, irrigation water can have significant
levels of nitrates, so it’s a good idea to have the irrigation
water tested. The nitrate contribution from irrigation water
should be taken into account when developing nutrient budgets, but there are many variables to consider:
uptake by plant, irrigation water going beyond root
system, and nitrate variability in water during the season.
Table 12 provides conversions to calculate parts per
million to lbs/acre inch.
PAN Plant-Available Nitrogen —
Nutrient Source: Soil N Mineralization
This is the process whereby the stock of N that is “stored”
in SOM decomposes to release plant-available nitrogen
(PAN). Because organic farmers typically apply more
organic matter than conventional farmers, PAN provided
by soil N mineralization generally increases under organic
management. The most recent organic inputs have the
most influence on PAN release from soil organic matter.
Most University nutrient management guides account for
some background soil N mineralization, but not usually
the high levels often found on established organic farms.
The potential rate of soil N mineralization is a function of
temperature, tillage, type of soil, and other factors. Any
figures developed for PAN from soil N mineralization
must be considered approximate.
While organic growers are required to record applications
of materials, they might not have the nutrient analyses
they need to do a calculation. Approximate numbers can
be used in this situation.
How to Estimate Soil N Mineralization
1. Organic amendments (composts, manure, cover
crops, fertilizers, etc.) applied to the soil will continue
to provide PAN in subsequent years, but in ever-smaller
quantities. Organic fertilizers such as blood meal,
and feather meal, which are higher in N, will provide
roughly 75% of their N in the first year and up to 50%
of their N within a week of application (Gaskell, 2007).
Assuming some materials have been applied, first calculate total N application per year. To determine the PAN
for the current year, refer to Tables 7-9. The estimation
rule for PAN available in years 1, 2, and 3 post-application
are 8%, 5%, and 3% of total N applied, respectively. See
Table 2, below.
2. If previous organic input history is not available,
then credit 50 lbs N/acre if the field received substantial
organic inputs (i.e. cover crops and manure or compost)
for at least three consecutive years.
PAN Plant-Available Nitrogen —
Nutrient Source: Manures and Compost
To determine PAN from manure and compost products you must first analyze the nitrogen content. Table 7,
Appendix A, based on Oregon State University’s Organic
Fertilizer and Cover Crop Calculator (Andrews, et al.),
identifies the PAN % or pounds after four weeks for
manure, compost, and other organic amendments.
In order to obtain the full N benefits of manure, applications should be incorporated immediately. Significant
amounts of ammonia-N can be lost within one to two
days of application through volatilization (see Table 5
Appendix A). Significant amounts of N may also be lost
if manure is applied too far in advance of the period of
rapid N uptake by the crop, even if the manure is incorporated. For fall manure applications, up to half of the
N may be lost by the time of greatest crop demand the
following year (Magdoff, 2009).
Poultry litter is a popular organic amendment because of
high N and P levels, but it may be high in arsenic, copper
and zinc due to additives in their feed. Analysis of poultry
litter should include Zn, Cu, and As to ensure that soil is
not being contaminated.
Manure and Compost
Refer to page 4 for additional National Organic Program
regulations related to the use of manure and compost on
organic farms. It should also be noted that manure and
compost inputs from non-organic sources are allowed as
long as there is no risk of contamination.
Table 2. Example of PAN Credits.
If you applied 2,000 lbs/acre of broiler litter this year, and this litter is 4% N, then a total of 2,000 x .04 = 80 lbs N/acre
was applied. This year, after ten weeks, the PAN from the 80 lbs applied will only be 45% or 36 lbs N (see Table 7). Next
year, a year after application, 8% of the total N applied would be available; 80 lbs/acre x .08 = 6.4 lbs/acre. Two years
after application, 5% of the N applied would be available (80 x .05 = 4lbs/acre and in year three, 3% would be available
(80 x .03 = 2.4/lbs/acre).
PAN, Percent of Total N (general rule)
45% x 80 lbs/acre
8% x 80 lbs/acre
5% x 80 lbs/acre
3% x 80 lbs/acre
Years After Application
current year
1
2
3
lbs PAN per acre
36
6.4
4
2.4
7
PAN Plant-Available Nitrogen —
Nutrient Source: Cover Crops
Cover crops and green manures provide both nitrogen
and organic matter to the soil. The amount of N and
organic matter provided will depend on the cover crop
species, or mix, crop biomass, and growth stage when
killed. These same factors will influence how rapidly the
cover crop will decompose, and whether it will release,
or immobilize PAN. Most PAN is released in four to six
weeks after cover crop termination. For a comprehensive
guide on this topic see ‘Estimating Plant Available
Nitrogen Release from Cover Crops, PNW 636’. In
this publication we will review the shortcut method as
outlined in that document.
PAN from any cover crop is minimal when the cover
crop is very small. For solo cover crops, the best time to
terminate the cover crop to maximize PAN depends on
whether the cover crop is a legume or a non-legume.
➣ PAN from a robust stand of legumes (Figure 4)
peaks at budding growth stage. PAN declines slowly
as reproductive growth continues.
➣ PAN from cereal residues is positive early in the
spring (through tillering, mid- to late March). As stem
elongation proceeds (jointing), PAN from cereal residues declines. By the time the flag leaf (uppermost
leaf) emerges (Feekes growth stage 8 or Zadoks 37),
PAN from cereal crop residue is near zero. When
cereal heads are visible, PAN from cereals is negative.
To maximize PAN, kill cereal cover crops early, but
wait until bud stage to kill legumes. In cereal/legume
mixtures, the best crop growth stage for maximum
PAN benefit depends on the percentage of legume in the
stand. Figure 4 illustrates how PAN changes over time
in solo and mixed cover crop stands.
➣ When the cover crop is mostly legume, it behaves
much the same as does a pure legume cover crop—
the PAN from crop residue increases until cereal boot
stage. (Feekes stage 10; Zadoks stage 45). After pure,
or majority cereal stands reach jointing stage, PAN
declines.
➣ When a cover crop has more cereal than legume
(25 percent legume line in Figure 4), it follows a
similar PAN curve as a solo cereal crop, but negative
PAN is usually not seen until the cereal reaches boot
stage (around mid-May).
Seeding legume/cereal mixes instead of a solo cereal
crop allows greater flexibility in timing of cover crop
8
Figure 4. Effect of kill date on typical plant-available N (PAN)
release from cereal, legume, or mixed stands. Based on
compilation of field data from Willamette Valley cover crop
trials. Figure from PNW 636, Estimating Plant-available
Nitrogen Release from Cover Crops (Sullivan and Andrews,
2012), ©Oregon State University. Used by permission.
termination without consequences of negative PAN.
Cover crop mixes also combine the N fixation benefits of
legumes with weed suppression and soil benefits of cereals.
The percent N in cereals varies with field history. Fields
that have a history of manure/compost application and/or
legumes in rotation often have higher percent N in cereal
than do fields with a history of only N fertilizer application.
Biomass determination. The first step in estimating PAN
from a cover crop is determining how much cover crop
biomass is present. Visual estimates of cover crop biomass
are not very accurate, especially for multi-species cover
crop mixes. Cutting and weighing cover crop biomass is
the preferred method to estimate PAN. Generally, cover
crop roots are not included in this calculation. Harvest
the above-ground cover crop with quadrats or a sickle bar
mower (see Sullivan et al. 2012, Appendix C, Section 5 for
additional sampling instructions). Any harvest method can
be used that gives you a clean plant sample with a known
harvest area.
To determine the PAN you’ll need to estimate the percent
dry matter (DM). You will need to either use a ballpark
estimate of DM or oven dry the sample that has been
collected. Mixed, vegetative cover crop DM will usually
be between 12 and 18%. Very wet clover samples are
usually 10 to 12 % DM. Cereals after head emergence
are usually 20 to 25% DM.
Table 3. Estimated plant-available N (PAN) release from decomposition of crop residues in soil
at 4 and 10 weeks
Total N
C:N
4 wk
10 wk
4 wk
10 wk
% N, dry wt
PAN, % of residue total N
lbs PAN/dry ton
Cereals after head emergence
1
40
-40
<0
-8
<0
2
20
5
20
2
8
Cereals, tillering/jointing
3
13
35
40
21
24
50/50 Cereal/Legume Mix or
Flowering Legumes
4
10
50
55
40
44
Legumes, vegetative
Adapted from OSU Extension publication EM9010-E (2010): Nutrient management guide for sweet corn (western Oregon).
Negative PAN values indicate immobilization of N by cover crop residue.
With a good stand and cover crop kill near bud or head emergence stage of plant development, the typical cover crop PAN
credit is 50 lb N/acre for cereal legume mixtures, and up to 100 lb PAN/acre for legumes.
Shortcut method. Harvest and measure cover crop biomass and use typical values for cover crop DM and percent
N (Table 3) to estimate PAN. See Table 9 for information
and sample calculations about how to estimate cover crop
contributions to PAN. More accurate estimations can be
made with lab analysis (Sullivan & Andrews, 2012).
☞
Enter figures for PAN available from previous
applications of manure, compost and cover crops
under Nutrient Sources section. Alternatively, use
the rates established in your state’s Nutrient
Management Planning tool.
Phosphorus (P)
In nature, most plants, except brassicas, receive much
of their phosphorus through mycorrhizal interactions
with the soil. This is particularly true in perennial systems. In organic systems, with regular cover crops, this
interaction may be more prominent than in conventionally managed systems because organically managed soils
can provide better conditions for mycorrhizal survival.
If manures, or composted manures, have been regularly
applied at rates to meet a crop’s N needs, this may result
in more P (and K) than the crop requires. After many
years, this can result in over-accumulation of P and K,
and any solution requires some combination of reduced
applications and/or increased uptake and removal of
these nutrients.
Potassium (K)
Potassium is available as a positive ion, or cation, and soils
with a high cation exchange capacity (CEC) will generally
have more capacity to store K. Most soils with high clay
content, high organic matter levels (>3%), or both will
Figure 5. Assessing the biomass of a cover crop.
have high CEC. There are thousands of pounds per acre
of potassium in an average, non-sandy soil, but most
of that is unavailable to plants—usually only 1-2% is
available. Repeated applications of manures can lead to
over-abundance of K (as well as P) in the soil.
Secondary Macronutrients and
Micronutrients
Micronutrients are important to plant health, and can
be limiting factors for both yield and quality in some
production systems, or, when present in excessive
amounts, can reduce availability of other nutrients or
have a negative impact on plant health. Soil tests should
provide information on the levels of the secondary
macronutrients Calcium (Ca), Sulfur (S), and Magnesium (Mg), as well as micronutrients, such as Manganese
(Mn), Iron (Fe), Zinc (Zn), Copper (Cu), and Boron (B).
Documented soil deficiency, either through soil or tissue
tests, is required per NOP regulations prior to applying
any synthetic micronutrients.
9
Section 3.
Determining Nutrient Application Rates
Determining nutrient application rates consists of taking
your crop’s nutrient needs and subtracting any credits
from the system. If the credits are less than the crop’s
nutrient need, the grower will need to apply supplemental
nutrients in order to achieve the desired yield. Not all of
the N applied this year will be available to the crop in
the first year. A balanced nutrient program will supply
sufficient PAN, P2O5, K 2O, and other nutrients while
avoiding excesses. The example below demonstrates this
approach.
Example
Assume that after all the nutrient credits are subtracted,
the values for the Nutrients Recommended for Yield are:
80 lbs PAN, 40 lbs P2O5, and 60 lbs K2O per acre.
The manure analysis is 3% N, or 60 lbs total N per dry ton.
According to Table 7, PAN Estimates for Uncomposted
Manure, at 10 weeks PAN released is about 30% of the product, or 18 lbs PAN per dry ton. This material is 60% dry matter
(therefore, 40% water), so to make consideration for this:
18 lbs PAN x 0.60 = 10.8 lbs PAN per “as is” ton
80 lbs PAN/ac ÷ 10.8 lbs PAN/Ton = 7.4 T/ac
This is the application rate that meets the crop’s
nitrogen need.
The manure also contains 20.6 lbs P2O5/dry ton (reported
on a dry basis this time) and 37.8 lbs K2O/dry ton according
to the analysis.
☞
Add up all the PAN nutrient credits from the
previous applications of manure, compost, cover
crops, as well as what can be expected from the
irrigation water for this season’s crop. This total
should be subtracted from the total Nutrients
Recommended for Yield.
To calculate how much P2O5 the 7.4 T/acre manure
application rate will provide:
Application rate: 7.4 T/ac x .6 (60% dry matter) x 20.6 lbs P2O5/
dry ton = 91.5 lbs P2O5/ac
91.5 lbs P2O5/ac is being applied with the 7.4 T/ac manure.
Note that this is over twice as much P2O5 as is required by the
crop. What are some other fertilizer options that would supply
sufficient N, but less P2O5?
To calculate how much K2O the 7.4 T/acre manure
application rate will provide:
Application rate: 7.4 T/ac x .6 (60% dry matter) x 37.8 lbs K2O/
dry ton = 168 lbs K2O/ac
168 lbs K2O/ac is being applied with the 7.4 T/ac manure. This is
nearly three times as much K2O/ac as is required.
What are some other fertilizer options that would supply
sufficient N and P, but less K2O/ac?
Refer to Tables 4-6 for additional organic fertilizer
options.
Please note: Calculations here use lbs N/ton or PAN/ton because litter and compost are commonly delivered by the ton.
☞
Enter planned NPK applications to the
right of line 7 (Manure), line 8 (Compost), or
line 9 (Specialty Fertilizers) in the appropriate
nutrient column.
10
Timing and Application Method
The timing, application, and incorporation methods
of nutrients is most important relative to conserving N
and P. Manure applications can provide significant N to
the soil if they are incorporated within 12 hours of application. If the manure is broadcast and left on the surface, between one half and two thirds of the available
N can be lost to volatilization after one week (see Table
5, Appendix A). Even in reduced-till systems, application
close to the time of planting will decrease the likelihood
of loss by runoff or erosion. Manures are generally best
applied just before soil tillage, but diligence is needed to
ensure that National Organic Program harvest-interval
regulations related to manure applications are followed.
N mineralized from manures during a rainy period may
leach N into the water table or, if eroded, may carry into
surface waters. Fall applications of manure on annual row
crops do risk considerable N loss, even if incorporated
in regions with significant winter/spring precipitation.
The ammonium is converted to nitrate, and then is subject
to leaching and denitrification before the N is available for
next year’s crop (Magdoff & Van Es, 2009). Denitrification
is the microbial conversion of nitrates to nitrous oxides,
and mostly occurs in soils that become anaerobic due to
high water tables, poor drainage, or surface sealing. But
regardless of the mechanism of N loss, the loss of N to
water or air should be minimized through applications of
N appropriate to plant needs. The forms of N applied, as
well as its time of application can influence the percentage
N taken up by plants, and lost to leaching or the atmosphere. The goal of N management is to have minimal
nitrate-N present in soil that could be leached through
rainfall or irrigation or denitrified. This may allow for
fall manure applications with low risk of N leaching
due to winter rains. Manures mixed with large amounts
of high-carbon bedding (straw or wood shavings) may
immobilize N during the early stages of decomposition,
and should be composted prior to application, or be
applied long enough prior to planting to reduce the risk
of immobilization.
Cover crop incorporation can be considered a fertilizer
application and as Figure 6 shows, the peak PAN generally
occurs after four weeks. That may be two or more weeks
before the crop has its highest demand for N. Attempting
to plant too soon after cover crop incorporation risks pest
and pathogen problems associated with the decomposing
cover crop.
Figure 6. Timing of nitrogen (N) mineralization from cover crop residue in relation to crop N uptake (adapted from Gaskell et al., 2006). From
Gaskell, M., and R. Smith. 2007. “Nitrogen Sources for Organic Vegetable Crops.” HortTechnology October-December 2007 vol. 17 no. 4, 431441) Note: Soil temperature plays an important role in the rate of N mineralization from soil organic matter.
11
Section 4.
Evaluating Risk of Leaching and Runoff
Risk factors associated with N leaving the field are not
quite the same as P leaving the field, although erosion
and runoff are risks common to both nutrients. These
elements act differently in the environment—P does
not volatilize and typically does not leach in significant
quantities.
Soils with active biology and good aggregate stability
will tend to absorb rainfall more easily. While this might
reduce the likelihood of P runoff through soil erosion,
leaching of N may still be a problem. Good aggregate
stability also encourages airflow into the soil, reducing the
risk of anaerobic conditions which cause denitrification
and loss of soil N.
Assessing Risk of N Leaving the Field
Risk Factors for P Leaving Field
Soil texture (sandy vs. clay)
Slope of land
Amount of cover on the soil
Amount and timing of nutrient application
Amount and timing of rainfall events
and irrigation
➣ Distance to perennial surface water
➣ High P levels in the soil
➣
➣
➣
➣
➣
Mitigation Practices to
Reduce P Loss from Field
➣ Keep crop residues on soil surface.
➣ Minimize duration of bare soil exposure to weather.
Nitrates (NO3), and ammonium (NH4+) are both easily
dissolved in water. As noted above in the ‘Timing’ section, ➣ Reduce length of slope using terraces, berms
(vegetated with grass or hedgerows).
application and incorporation of manures close to time of
planting will help reduce risks from volatilization, leaching, ➣ Tailwater ponds reduce sediment in runoff.
➣ Reduce amount of P in soil surface over time by
and runoff. Fall manure applications risk significant N
reducing the application rates for manure, compost
loss even if incorporated.
or other products with high P content.
P Indices for the Pacific Northwest States ➣ No-till or minimum till may increase water soluble P
loss from a field via heavy rainfall or irrigation
events, even though no-till does reduce total P loss
As of July 2013, all states are reviewing and updating
from erosion.
their P-indices.
12
Figure 7. Organic management builds a soil full of aggregates and organic
matter. Photo: Oregon Tilth
Section 5.
Calculating Nutrient Application Rates Based on Risk Analysis
In previous sections, you developed numbers for nutrient levels already in the ground from previous manure/
compost applications, cover crops, and irrigation water.
You also developed numbers for nutrient levels required
by the crop. If crop nutrient requirements exceed your
nutrient availability estimates, then additional nutrients
are required. Refer to Tables 4-6, Appendix A for a listing of organic nutrient sources and their N-P-K values.
Review the P-Index for your state for detailed guidance.
☞
Estimates for PAN and nutrient applications
should be reviewed, and sources and amounts of
nutrients to be applied should be revised as appropriate in light of P-Index policy. Add up lines 7, 8,
and 9 under Nutrient Sources for “planned” and follow instructions in line 11, and the text in red at the
bottom of the table.
Record keeping
Organic farmers are required to maintain extensive
records about their crops, crop rotations, inputs, and
other practices used on their farms, including a soil
fertility management plan. The 590 implementation
requirement developed by following this guide
can likely be used to meet many of the requirements
related to soil fertility. Additionally, this information
can be used to help organic growers track the trajectory of the SOM because organic rules state that the
grower must maintain or improve SOM content.
Figure 8. A diversified organic farm manages nutrients in blocks to ensure the varying conditions and crops are appropriately considered.
Photo: Sarah Brown (Oregon Tilth)
13
Appendix A. Tables
Table 4. Nutrient analysis (percent by weight) of common organic fertilizer materials
(Gaskell et al., 2007)
Potassium (% K2O)
Material
Nitrogen (% N)
Phosphorus (% P2O5)
Chilean nitrate
Blood meal
Feather meal
Fish meal/powder
Seabird & bat guano
Meat and bone meal
Soybean meal
Processed liquid fish residues*
Alfalfa meal
Pelleted chicken manure
Bone meal
Kelp
Soft rock phosphate
Potassium-magnesium sulfate
Cocoa shells
Cottonseed meal
Granite dust
Hoof & horn meal
Seaweed, ground
Muriate of potash (KCI)
16
12
12
10-11
9-12
8
7
4
4
2-4
2
<1
0
0
1
6
0
11
1
0
0
0
0
6
3-8
5
2
2
1
1.5
15
0
15-30**
0
1
2
0
2
0.2
0
0
0
0
2
1-2
1
1
2
1
1.5
0
4
0
22
3
2
5
0
2
60
* Note: all analyses are % by weight, as specified in state fertilizer laws. For liquids, product density (weight per gallon)
should be used to calculate nutrient application rate: (g/ac)*(lb nutrient/g)=(lb nutrient/ac)
* *Soft rock phosphate provides only 1-3% of its P in acid soils, and little or no P in soils with pH over 7.
14
Table 5. Nutrient Content of Common Animal Manures and Manure Composts
This table includes general estimates of nutrient availability for manures and composts. These can vary widely depending on animal feed, management of grazing, the age of the manure, amount and type of bedding, and many other factors.
Manure applications must be done in accordance with NOP 205.203 C.1-3. See page 4.
Production Guide for Organic Snap Beans for Processing. 2012. (A. Seaman, ed.) Cornell University Coop¬erative Extension.
50 p. http://nysipm.cornell.edu/organic_guide/bean.pdf
Total N P2O5
K2O
Nutrient content lbs/ton
Dairy (with bedding)
Horse (with bedding)
Poultry (with litter)
Composted dairy manure
Composted poultry manure
Pelleted poultry manure 3
Swine (no bedding)
N1 1
N2 2
P2O5
K2O
Available nutrients lbs/ton in first season
9
14
56
12
17
80
4
4
45
12
39
104
10
14
34
26
23
48
6
6
45
3
6
40
2
3
16
2
5
40
3
3
36
10
31
83
9
13
31
23
21
43
10
9
8
8
3
7
7
Nutrient content per 1000 gal
Available nutrients per 1000 gal in first season
Swine finishing (liquid)
50
55
25
25 *
20 +
44
23
Dairy (liquid)
28
13
25
14 *
+
10
23
11
1. N1 is an estimate of the total available for plant uptake when manure is incorporated within 12 hours of applications.
2. N2 is an estimate of the total N available for plant uptake when manure is incorporated after 7 days.
3. Pelletized poultry manure compost.
* injected
+ incorporated
15
Table 6. Pounds of fertilizer/acre needed to provide 20 to 100 pounds of N, P, K per acre.
This table is divided into three sections. Production Guide for Organic Snap Beans for Processing. 2012. (A. Seaman,
ed.) Cornell University Cooperative Extension. 50 p. http://nysipm.cornell.edu/organic_guide/bean.pdf
Sources of Nitrogen
Blood meal 13% N
Soy meal 6% N (x 1.5*)
also contains 2% P and 3% K2O
Pounds of fertilizer per acre to provide
20 to 100 pounds of N per acre
20# N
40
60
80
100
150
310
460
620
770
500
1,000
1,500
2,000
2,500
Fish meal 9% N (also contains 6% P2O5)
220
440
670
890
1,100
Alfalfa meal 2.5% N
also contains 2% P and 2% K2O
800
1,600
2,400
3,200
4,000
Feather meal, 15% N (x 1.5*)
Chilean nitrate 16% N
cannot exceed 20% of crop’s need.
200
400
600
800
1,000
125
250
375
500
625
Sources of Phosphorus
Pounds of fertilizer per acre to provide
20 to 100 pounds of P2O5 per acre
20# P205
40
60
80
100
Bonemeal 15% P2O5
130
270
400
530
670
Rock Phosphate 30% total P2O5 (x 4*)
270
530
800
1,100
1,300
Fish meal 6% P2O5 (also contains 9% N)
330
670
1,000
1,330
1,670
Sources of Potassium
Pounds of fertilizer per acre to provide
20 to 100 pounds of K2O per acre
20# K2O
40
60
80
100
Sul-Po-Mag 22% K2O (also contains 11% Mg)
90
180
270
360
450
Wood ash (dry, fine, grey) 5% K2O, also raises pH
400
800
1,200
1,600
2,000
Alfalfa meal 2% K2O also contains 2.5% N
1,000
2,000
3,000
4,000
5,000
Greensand or Granite dust 1% K2O (x 4*)
8,000
16,000
24,000
32,000
40,000
40
80
120
160
200
Potassium sulfate 50% K2O
* Application rates for some materials are multiplied to adjust for their slow-to-very-slow release rates.
16
Table 7. Plant-Available Nitrogen (PAN) Estimates for Uncomposted Manure
This table is based on Oregon State University’s organic fertilizer calculators, which compare the nutrient values and cost
of cover crops, organic and synthetic fertilizers, and compost. One calculator is for larger acreages, providing numbers on a
per-acre basis, and one is for smaller plots, providing numbers on a per-square-foot basis. These tools help calculate organic
fertilizer needs and can be accessed at http://smallfarms.oregonstate.edu/node/175833/done?sid=476
Total N analysis
(percent dry weight)
of uncomposted fresh
manure or other
uncomposted organic
fertilizer product
Your value
Total N
(% dry weight)
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
7.0
8.0
9.0
10.0
11.0
12.0
PAN
Estimate
After
After
4 weeks 10 weeks
% PAN
% PAN
-23
-15
-8
0
8
15
23
30
38
45
53
60
60
60
60
60
60
60
-8
0
8
15
23
30
38
45
53
60
68
75
75
75
75
75
75
75
Total N analysis
(lbs N per dry ton)
of uncomposted
fresh manure or other
uncomposted organic
fertilizer product
Your value
lb total N
per dry ton
10
20
30
40
50
60
70
80
90
100
110
120
140
160
180
200
220
240
PAN
Estimate
After
After
4 weeks
10 weeks
lbs PAN
lbs PAN
per dry ton per dry ton
-2
-1
-3
0
-2
2
0
6
4
11
9
18
16
26
24
36
34
47
45
60
58
74
72
90
84
105
96
120
108
135
120
150
132
165
144
180
17
Table 8. Estimated Plant Available Nitrogen (PAN) from Finished Compost
This table is based on the PAN equation used with the Oregon State University Organic Fertilizer and Cover Crop Calculator,
http://smallfarms.oregonstate.edu/calculator
Total N analysis of
finished compost
Your value
Total N (% dry wt)
1.0
1.5
2.0
2.5
3.0
PAN Estimate
10 wk
% PAN
0
5
10
10
10
Total N analysis of
finished compost
Your value
lb total N per dry ton
20
30
40
50
60
PAN Estimate
10 wk
lb PAN per dry ton
0
1.5
4.0
5.0
6.0
Source: OSU Fertilizer & Cover Crop Calculator (online; 2013)
Instructions
1.
2.
3.
Find %N analysis of the compost in “Total N analysis” column.
PAN estimates are listed on the same row in units of “%PAN” or “lb PAN per dry ton.”
To get PAN estimate for “as-is” moisture content, multiply Table PAN estimate (given for oven dry product; 100% dry
matter) x %DM/100 in “as-is” manure.
Example
Lab analysis of a compost is 1.5% N or 30 lb N per ton (dry weight basis).
The “as-is” fertilizer product contains 40% dry matter and 60% moisture.
From the Table above, PAN released in soil after 10 wk is estimated to be 5% of product total N analysis (dry weight basis),
or 2 lb PAN per dry ton.
At “as-is” dry matter content (40% in this example), the product provides about 0.8 lb PAN per “as-is” ton
(calculated as 2 lb PAN per dry ton x 0.4).
Use this table only when you are sure that compost is “finished”. Many poultry litter “composts” that smell of ammonia
are not “finished” and they have PAN similar to fresh manure.
Additional Considerations
Compost analysis for mineral N (ammonium + nitrate-N) can provide useful data to guide application rate.
First year PAN release from compost is approximately equal to the sum of ammonium + nitrate-N applied.
Very little first-year PAN comes from mineralization of organic N in finished compost.
Composts usually contain less than 3% total N. “Composts” with more than 3% N are often not finished, they are
dried manure.
18
Table 9. Estimated Plant Available Nitrogen (PAN) from Cover Crops
Table from PNW 636, Estimating Plant-available Nitrogen Release from Cover Crops (Sullivan and Andrews, 2012),
©Oregon State University. Used by permission.
Total N analysis
of cover crop
Your value
Total N (% dry wt)
1.0
1.5
2.0
2.5
3.0
3.5
4.0
PAN Estimate
After 10 weeks
% PAN
Total N analysis
of cover crop
Your value
lb total N per dry ton
PAN Estimate
After 10 weeks
lb PAN per dry ton
0
13
23
32
40
47
54
20
30
40
50
60
70
80
0
4
9
16
24
33
43
Rationale
Cover crop PAN can be estimated by a variety of methods.
A general approach to estimating cover crop PAN is provided in the SARE publication “Managing Cover Crops Profitably.”
The SARE approach uses “rule of thumb” estimates of cover crop biomass and N concentration and PAN.
The approach described here is for growers who are willing to make some on-site measurements to estimate PAN
from cover crops.
Approach
• A laboratory analysis for cover crop total N as a percentage in dry matter (DM) is a good predictor of a cover crop’s
capacity to release PAN for the summer crop.
• When cover crops contain a low N percentage (<1.5% N in DM), they provide little or no PAN.
• When cover crops contain a high N percentage (3.5% N in DM) they provide approximately 35 lb PAN per ton of dry
matter.
• PAN release increases linearly, as cover crop N percentage (in DM) increases from 1.5 to 3.5%.
• Cover crops decompose rapidly, and release or immobilize PAN rapidly. Most PAN is released in 4 to 6 weeks after cover
crop kill.
• Values for cover crop PAN listed here are most applicable to winter cover crop/summer vegetable crop rotations in
western Oregon and Washington.
• The timing of PAN release will differ in regions outside of western WA and OR, but we expect a strong relationship
between cover crop N% and PAN to be found in most locations.
Instructions
The table above is reproduced from PNW Extension publication 636, Estimating Plant-available Nitrogen Release from
Cover Crops. To use these tables you will need to have either taken a lab analysis of your cover crop to identify the total %N
or will be using an estimate based on Table 3.
1. Find %N analysis of the cover crop in “Total N analysis” column (far left). PAN estimates are listed on the same row in
units of “%PAN” expressed as a percentage of total %N, or “lb PAN per dry ton.”
Example
The fresh weight of a rye/vetch cover crop is about 16.5 tons/ac (33,000 lbs/ac). With 15% dry matter the cover crop
produced 4,950 lbs dry matter/ac.
If total %N is analyzed or estimated to be 3%, percent PAN is approximately 40% (table 9). Multiply 4,950 lbs dry matter x
(3/100) x (40/100) = 59 lbs PAN/ac.
19
Appendix B.
Conversion Tables
Table 10. Converting pounds per acre to
pounds per 1000 square feet
Pounds per
acre
50
75
100
125
150
175
200
225
250
275
300
325
350
375
400
Pounds per 1000
square feet
1.1
1.7
2.3
2.9
3.4
4.0
4.6
5.2
5.7
6.3
6.9
7.5
8.0
8.6
9.2
One acre = 43,560 square feet
X lbs per acre = Y lbs per 1000 square feet
Example
Example 100 lbs per acre = 3.7 oz per 100 square feet
(100 lbs = 1,600 oz;
1,600 divided by 43,560 = .037 oz per sq. ft.; multiply by
100 to get 3.7 oz per 100 sq. ft.)
Table 11. Converting percentages of material
per dry ton to pounds of material per dry ton
Percent of material Pounds of material
dry weight basis
per dry ton
0.5
10
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
6.5
7
7.5
8
8.5
9
9.5
10
10.5
11
11.5
12
20
30
40
50
60
70
80
90
100
110
120
130
140
150
160
170
180
190
200
210
220
230
240
X percent of material per dry ton = Y lbs of material
per dry ton
Example
.5% per dry ton = 10 lbs per dry ton
(.5% of material per dry ton =
.005 x 2,000 lbs per dry ton =
10 lbs of material per dry ton)
20
Table 12. Nutrient Management Conversion Factors
Measurement
Unit
Symbol
Multiply
by
To Obtain
Symbol
Volume
acre-inch
gallon
ac-in
gal
27000
8.35
gallon
pound
gal
lb
Concentration
parts per million
ppm or mg/
kg
ppm or mg/L
ppm or mg/L
%
%
%
%
lb/1000 gal
0.002
pound/ton
lb/t
0.00835
0.227
20
83.5
2266
10000
27
pound/1000 gallon
pound/acre-inch
pound/ton
pound/1000 gallon
pound/acre-inch
parts per million
pound/acre-inch
lb/1000 gal
lb/ac-in
lb/t
lb/1000 gal
lb/ac-in
ppm
lb/ac-in
parts per million
parts per million
percent
percent
percent
percent
pound/
1000 gallon
Dry or wet
Nutrients
percent dry matter
(total solids)
percent moisture
manure,
dry wt. basis
% DM
0.01
solids fraction
DM
% moisture
0.01
100/(%DM)
moisture fraction
manure,
“as-is” basis
MF
phosphorus
P
2.29
phosphate
P2O5
potassium
K
1.20
potash
K 2O
nitrogen
in nitrate form
nitrogen
in ammonium form
NO3- N
1
nitrogen
N
NH4- N
1
nitrogen
N
21
Appendix C.
References to NRCS Publications and Other Resources
National Organic Program
www.ams.usda.gov/AMSv1.0/nop
Section 1. Determining Crop’s Need for
N, P, and K (page 5)
Baldwin et al. Crop Rotations on Organic Farms.
www.cefs.ncsu.edu/resources/organicproductionguide/
croprotationsfinaljan09.pdf
California Department of Food and Agriculture’s
(CDFA) Fertilizer Research & Education Program.
www.cdfa.ca.gov/is/fflders/frep.html
Collins, D. Washington State University, Soil Testing:
A Guide for Farms with Diverse Vegetable Crops.
https://pubs.wsu.edu/ItemDetail.aspx?ProductID=15520
&SeriesCode=&CategoryID=&Keyword=EM050E
Cornell Guides for Organic Fruits, Vegetables and
Dairy. http://nysipm.cornell.edu/organic_guide/
Gaskell, M., R. Smith, J. Mitchell, S.T. Koike, C.
Fouche, T. Hartz, W. Horwath, and L. Jackson. 2006.
Soil Fertility Management for Organic Crops. University
of California. 8 p.
http://anrcatalog.ucdavis.edu/pdf/7249.pdf
Idaho Nutrient Management, www.extension.uidaho.
edu/nutrient. Look under Crop Nutrient Requirements.
Oregon State University Nutrient Management Guidelines for Crops.
http://extension.oregonstate.edu/catalog/details.php?searc
h=nutrient+management&submit.x=0&submit.y=0
Minnesota Vegetable Nutrient Management Guide.
www.extension.umn.edu/distribution/cropsystems/
dc5886.html
Mohler, et al. 2009. Crop Rotation on Organic Farms.
http://palspublishing.cals.cornell.edu/nra_order.taf?_
function=view&ct_id=40
Section 2. Developing Nutrient Credits
(pages 6-9)
Andrews, N., D. Sullivan, J. Julian, and K. Pool. Oregon State University Organic Fertilizer and Cover Crop
Calculators. http://smallfarms.oregonstate.edu/
node/175833/done?sid=476
Bowman, G., C. Shirley, and C. Cramer. 1998.
Managing Cover Crops Profitably. SARE Publication.
212 p. www.sare.org/publications/covercrops/
covercrops.pdf
California Department of Food and Agriculture’s
(CDFA) Fertilizer Research & Education Program.
www.cdfa.ca.gov/is/fflders/frep.html
Cornell Guides for Organic Fruits, Vegetables and
Dairy. http://nysipm.cornell.edu/organic_guide/
Gaskell, M., R. Smith, J. Mitchell, S.T. Koike, C.
Fouche, T. Hartz, W. Horwath, and L. Jackson. 2006.
Soil Fertility Management for Organic Crops. University of California. 8 p.
http://anrcatalog.ucdavis.edu/pdf/7249.pdf
Idaho Nutrient Management. www.extension.uidaho.
edu/nutrient, look under Crop Nutrient Requirements
Jackson, B.P., P.M. Bertsch, M.L. Cabrera, J.J. Camberato, J.C. Seaman, C.W. Wood. 2003. Trace element
speciation in poultry litter. J Environ Qual. 2003 MarApr., 32(2):535-40.
Magdoff, F., and H. Van Es. 2009. Building Soils for
Better Crops. SARE. 292 p.
www.sare.org/Learning-Center/Books/Building-Soilsfor-Better-Crops-3rd-Edition
Miyao, G., P. Robbins, and M. Cain. 2001. Winter cover crops before late-season processing tomatoes
for soil quality and production benefits. Final Report
Summary, CDFA Fertilizer Research and Education
Program (FREP).
Oregon State University Fertilizer/Nutrient Management Guidelines for Crops
http://extension.oregonstate.edu/catalog/details.php?sor
tnum=0134&name=Fertilizer+Guides&cat=Agriculture
22
Schonbeck, M.W. 1988. Cover Cropping and Green
Manuring on Small Farms in New England and New
York: An Informal Survey. East Falmouth, MA. New
Alchemy Research Report #10.
Sullivan, D.M. and N.D. Andrews. 2012. Estimating
plant-available nitrogen release from cover crops. Pacific
Northwest Extension Publication 636. Oregon State
University Extension. Corvallis, OR. 23 p.
Zimmer, Gary F. 2000. The Biological Farmer. Acres,
USA. 352 p.
Organic Fertilizer Association of California.
www.organicfertilizerassociation.org
Available N, P and K in Organic Fertilizer
Available N in Organic Fertilizers (in Production Guide
for Organic Snap Beans for Processing). 2012. Cornell
University Cooperative Extension. 50 p. http://nysipm.
cornell.edu/organic_guide/bean.pdf
NRCS Agricultural Waste Management Field
Handbook. www.nrcs.usda.gov/wps/portal/
nrcs/detailfull/national/technical/ecoscience/
mnm/?&cid=stelprdb1045935
Section 3. Determining Nutrient Application Sullivan, D.M. and N.D. Andrews. 2012. Estimating
plant-available nitrogen release from cover crops. Pacific
Rates (pages 10-11)
Andrews, N., D. Sullivan, J. Julian, and K. Pool. Oregon State University Organic Fertilizer and Cover Crop
Calculators. http://smallfarms.oregonstate.edu/
node/175833/done?sid=476
Gaskell, M., and R. Smith. 2007. Nitrogen Sources
for Organic Vegetable Crops. HortTechnology OctoberDecember 2007 vol. 17 no. 4, 431-441)
Section 4. Evaluating Risk of Leaching and
Runoff (page 12)
Magdoff, F., and H. Van Es. 2009. Building Soils for
Better Crops. SARE. 292 p.
www.sare.org/Learning-Center/Books/Building-Soilsfor-Better-Crops-3rd-Edition
Northwest Extension Publication 636. Oregon State
University Extension. Corvallis, OR. 23 p.
Plant-Available Nitrogen (PAN) from Cover Crops
Selected characteristics of important cover crops for California, in: Selecting the right cover crop gives multiple
benefits, Ingels, C., et al. October 1994.
http://ucce.ucdavis.edu/files/repository/calag/
tab4805p45.jpg
Sullivan, D.M. and N.D. Andrews. 2012. Estimating
plant-available nitrogen release from cover crops. Pacific
Northwest Extension Publication 636. Oregon State
University Extension. Corvallis, OR. 23 p.
Other Resources
eOrganic provides resources for people seeking infor-
Section 5. Calculating Nutrient Application
Rates Based on Risk Analysis (page 13)
23
mation about organic agriculture. The website is part
of eXtension, which draws on the expertise of staff at
American land-grant universities and extension programs. www.eorganic.info
ATTRA’s Sources of Organic Fertilizers and Amendments Database.
https://attra.ncat.org/attra-pub/org_fert/
Building Soils for Better Crops
and
Crop Rotation on Organic Farms: A Planning Manual.
These and many other useful publications are free to
download from the USDA’s Sustainable Agriculture
Research and Education SARE.
www.sare.org/Learning-Center/Books
Cornell’s Soil Health Assessment Training Manual
Free to download at: http://soilhealth.cals.cornell.edu/
extension/manual.htm
Manures for Organic Crop Production. George
Kuepper. 2003. ATTRA publication IP127.
www.attra.ncat.org/soils.html
Regional Organic Fertilizer Vendors
CALIFORNIA
Harmony Farm Supply
3244 Gravenstein Hwy North
Sebastopol, CA 95472
Mailing address: P.O. Box 460, Graton, CA 95444
(707) 823-9125
New Era Farm Service
2904 East Oakdale Avenue
Tulare, CA 93274
Telephone: (559) 686-3833
Fax: (559) 686-1453
www.newerafarmservice.com
Recology (www.thecompoststore.com) operates several
composting sites:
Grover Environmental Products
3909 Gaffery Road
Vernalis, CA 95385
(866) 764-5765
Ohio State University’s The Biology of Soil
Compaction Fact Sheet (2009).
ohioline.osu.edu/sag-fact/pdf/0010.pdf
Feather River Organics
3001 North Levee Road
Marysville, CA 95901
Organic Center’s Assessing Soil Quality in Organic
Agriculture (2006). www.organic-center.org/reportfiles/
SoilQualityReport.pdf
South Valley Organics
3675 Pacheco Pass Highway
Gilroy, CA 95020
NRCS Soil Quality/Soil Health website.
www.soils.usda.gov/sqi
Jepson Prairie Organics
6426 Hay Road
Vacaville, CA 95687
Mailing Address:
235 North First Street, Dixon, CA 95620
(800) 208-2370
Fax: (707) 678-5148
Soil Fertility in Organic Systems: A Guide for Gardeners and Small Acreage Farmers (2013). Pacific
Northwest Extension Publication 646.
https://pubs.wsu.edu/ItemDetail.aspx?ProductID=1558
5&SeriesCode=&CategoryID=&Keyword=646
Web Soil Survey. http://websoilsurvey.nrcs.usda.gov/
app/HomePage.htm
Sonoma Compost
550 Mecham Road
Petaluma, CA 94952
Phone: (707) 664-9113
Fax: (707) 664-1943
www.sonomacompost.com
Peaceful Valley Farm & Garden Supply
125 Clydesdale Court
P.O. Box 2209
Grass Valley, CA 95945
(888) 784-1722
www.groworganic.com
24
Z-Best Composting Facility
980 SR-25 (Hwy. 25 and Bolsa Road)
Gilroy, CA 95020
Phone: (408) 846-1573, (408) 263-2384
Fax: (408) 263-2393
www.z-best.com
IDAHO
OREGON
Concentrates, Inc. Organic Agriculture Specialists
5505 S.E. International Way
Milwaukie,OR 97222
(503) 234-7501, (800) 388-4870
Fax: (503) 234-7502
www. concentratesnw.com
Marion Ag Supply
Farm Store: 1-888-814-5727
503-633-4281
http://www.marionag.com/locations.htm
Naomi’s Organic Farm Supply
2615 SE Schiller St.
Portland, OR 97206
(503) 517-8551
www. naomisorganic.blogspot.com
Nature’s Needs
9570 NW 307th Avenue
North Plains, OR 97133
(503) 647-9489
Fax: (503) 647-9485
NW Greenlands
2200 NE Orchard Avenue
McMinnville, OR 97128
(503) 434-1671
2140 Turner Road
Salem, OR 97302
(503) 585-4510
8712 Aumsville Hwy SE
Salem, OR 97317
(503) 749-3117
NEVADA
25
Appendix D.
Implementation Requirement Worksheet
590 Organic NMP Implementation Requirement (IR)
Natural Resources Conservation Service
NUTRIENT MANAGEMENT SPECIFICATION SHEET
Client:
County:
Prepared by:
Jan-13
Tract:
Fields:
Date:
Acres:
DESIGN APPROVAL:
Practice
Code
NO.
590
PRACTICE
LEAD
DISCIPLINE
Nutrient
CED-EE&
Management BSCD-Agron
JOB CLASS
CONTROLLING
FACTOR
UNITS
I
II
III
IV
Area
Acres
160
320
640
All
This practice is defined as Job Class:
Design Approved by: /s/
Job Title:
Date:
CLIENTS’ ACKNOWLEDGEMENT STATEMENT:
The Client acknowledges that :
a. They have received a copy of the specification and understand the contents and requirements.
b.
The following information must be provided to NRCS by the client before this practice can be certified
as applied :
❏ Nutrient management application records including soil, water plant and organic byproduct test
results as specified in the plan;
❏ Documentation of quantities, analyses, sources, dates, and application methods of nutrients applied;
documentation of weather conditions and soil moisture at the time of application, documentation of
lapsed time to manure incorporation, rainfall, or irrigation.
❏ Periodic review of nutrient management including adjustments made; at a minimum this plan will
be reviewed with each soil test cycle.
c. It shall be the responsibility of the client to obtain all necessary permits and/or rights, and to comply
with all ordinances and laws pertaining to the application of this practice.
Accepted by: /s/________________________________________ Date: _____________________
CERTIFICATION
I have completed a review of the information provided by the client and certify this practice has been applied.
Certification by: /s/______________________________________________ Date:______________________
Job Title: _____________________________________
The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or
because all or a part of an individual’s income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with
disabilities who require alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA’s TARGET
Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimination write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue, S.W., Washington, D.C. 20250-9410 or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider and employer.
26
Organic Nutrient Management Specification
Natural Resources Conservation Service
NUTRIENT MANAGEMENT PLAN
Client: Tract Number:
Field Numbers:
Select all purposes that apply
❏ Budget and supply adequate nutrients for plant production
❏
❏
❏
❏
❏
Minimize ag nonpoint source pollution of surface and groundwater resources (water quality)
Properly utilize manure/organic materials as a plant nutrient source
Maintain or improve soil condition
Protect air quality by reducing nitrogen emissions (ammonia and NOx compounds) and the formation of particulates
Attach an aerial photo or site map showing fields where nutrient management is being implemented
NOTE: You may have criteria to meet that are NOT handled in this job sheet, please refer to the standard.
FIELD AND CROP INFORMATION
List crop rotation. Identify current crop with a check.
P Index:
No Data
Current
Crop
❏
❏
❏
❏
❏
❏
Soil Test Information*
Date:
Depth:
N (NO3 + NH4)
P
Soil Map Unit:
Yield
units
Laboratory Used:
Certified Lab
❏
K
pH
OM%
Other:
Use ppm for units, refer to last page of job sheet for conversions
* For some crops (e.g., berries and tree fruit), Extension recommends using leaf analysis rather than soil tests.
RECOMMENDED NUTRIENTS TO MEET YIELDS
PAN
(lbs/acre)
P2O5
(lbs/acre)
K2O
(lbs/acre)
pH
Reference:
Notes on Adjustments:
27
NUTRIENT SOURCES
Credits
PAN
(lbs/acre)
P2O5
(lbs/acre)
K2O
(lbs/acre)
Other__
(lbs/acre)
Planned
Planned
Planned
Planned
1. Adjustment to soil
N Mineralization
2. Nitrate from irrigation water
3. Nitrogen from previous cover crop
4. Other source(s)
5. TOTAL CREDITS
6. FINAL NUTRIENTS
RECOMMENDED FOR YIELD
(FOR UPCOMING CROP)
Nutrients to be applied to the field.
Rate (lbs/acre)
7. Manure** rate per acre
8. Compost*** rate per acre
9. Specialty Organic Fertilizer
Product:
Analysis:
10. Total Organic Inputs
(add lines 7, 8, and 9)
11. Nutrient status
(subtract line 6 from line 10)
If the number on line 11 is positive, this indicates over application.
If the number on line 11 is negative, this indicates under application.
If the number is 0, then planned applications meet and do not exceed crop requirements.
Include an explanation of these numbers, especially as they relate to the Phosphorus Index.
Describe Timing below (when organic applications are and are not going to occur) and Application Methods (surface applied
with or without incorporation, time lapse until incorporation, applied at planting with tillage, injected, and other details relevant to how the organic amendments are applied).
Other Information/ Considerations to Nutrient Management Plan: 1) Calibration of application equipment is required.
See Calibration tab for guidance on equipment calibration. Fillable calibration worksheets are available on Oregon’s eFOTG,
Section IV, Conservation Practices, WasteUtilization (633) Job Sheet and shall be attached to this nutrient management plan and
reviewed with the producer.
*These values are developed, in part, from the soil tests.
**Manure: Manure can be applied to organically grown crops, but with pre-harvest interval (PHI) restrictions.
(See page 2, sections C. 1-3.) How the crop is grown and harvested with regard to soil contact will determine which pre-harvest
interval is to be used.
***Compost: Only agricultural products can be certified. Thus, soil and compost are not eligible for organic certification. However, see page 2, §205.203, C.2i-iii relating to how compost can be used and produced on organic farms.
28
Additional information/requirements
❑
❑
Location of sensitive areas
Soil test schedule including designation of critical fields
Nutrient Application Bullets
❑
❑
❑
❑
* Apply nutrient materials uniformly to application area(s).
* Nutrients shall not be applied to frozen, snow-covered, or saturated soil if
the potential risk for runoff exists.
*Nutrient applications associated with irrigation systems shall be applied in
a manner that prevents or minimizes resource impairment.
*Calibrate application equipment to ensure recommended rates are
applied. See attached information on equipment calibration.
Operation and Maintenance
The client is responsible for safe operation and maintenance (O&M) of the practice. O&M includes:
• Periodic plan review:
At a minimum, plans will be reviewed and revised with each soil test cycle.
• Conduct additional manure analyses when there are significant changes in animal numbers
and/or feed management.
• Calibrate application equipment to within __% of the recommended rate.
• Document the actual rate at which nutrients were applied.
• Handle all nutrient material with caution.
• Wear appropriate protective clothing.
• Clean up residual materials from equipment and recycle or dispose of properly.
• Recordkeeping: soil/water/organic materials analyses, quantities/analyses/sources
of nutrients applied, dates and methods of application, weather conditions and soil moistures
at the time of application, lapsed time to incorporation/rainfall/irrigation, crops planted,
planting/harvest dates, crop yields, crop residues removed, and the specifics of plan reviews.
29
The Waste Utilization Worksheet below can be used to develop estimates for the lbs/acre of nutrients applied
to a field in the form of “waste,” an unfortunate term in this context. Proper calibration of application machinery
is needed to know how much material has been applied, but the nutrient analysis of the material must also
be known in order that the lbs nutrient/acre can be calculated.
633 OR-Specification
Natural Resources Conservation Service
May 2003
WASTE UTILIZATION WORKSHEET
Spreader Equipment Calibration
(Using a Full Spreader Load)
Name:
Date:
Operator:
Spreader ID:
Perform the following operations to calibrate the solids spreader equipment:
! Determine the weight of the waste material loaded in the spreader by using truck scales to weigh the
spreader equipment when it is empty and full.
! Spread the loaded spreader on the field using consistent speed and spreader settings to cover the field
uniformly. Spread in a rectangular pattern so the area calculation will be simple. Record engine rpm and
gear settings used.
! Measure the length and width covered by the full load and compute the application rate in tons per acre using
this worksheet.
Data and Calculations:
Steps
1. Date of calibration test2. Engine RPM during spreading 3. Gear selected during spreading 4. Weight of empty spreader (lb) =
5. Weight of loaded spreader (lb) =
6. Weight of Waste in spreader (lb) line 5 – line 4 =
7. Length of spreading area (ft) =
8. Width of spreading area (ft) =
9. Area spread (sq ft) line 7 x line 8 =
10. Waste applied (lb/sq ft) –
line 6 ! line 9=
11. Convert to tons per acre Line 10 x 21.78=
12. Average Application Rate (tons per
acre) – Sum of values in cells A11
through F11 divided by the total
number of calibrations completed =
Additional Notes:
30
A
B
ID of Calibration Test
C
D
E
F
Northwest
PDF
3984, 3984, Nutrient-Management-in-Organic-Systems-Western-States-Implementation-Guide.pdf, Nutrient-Management-in-Organic-Systems-Western-States-Implementation-Guide.pdf, 2129055, https://cms.organictransition.org/wp-content/uploads/2024/01/Nutrient-Management-in-Organic-Systems-Western-States-Implementation-Guide.pdf, https://cms.organictransition.org/resource/nutrient-management-plan-for-organic-systems-western-state-implementation-guide/nutrient-management-in-organic-systems-western-states-implementation-guide-pdf/, , 1, , , nutrient-management-in-organic-systems-western-states-implementation-guide-pdf, inherit, 3983, 2024-01-08 08:09:14, 2024-01-08 08:09:14, 0, application/pdf, application, pdf, https://cms.organictransition.org/wp-includes/images/media/document.png
2014