Daniel Geisseler, Ph.D.; UCCE Specialist in Nutrient
Management; Department of Land, Air and Water Resources,
University of California, Davis
Patricia Lazicki; Department of Land, Air and
Water Resources, University of California, Davis
Reviewers:
Rob Wilson; Director Intermountain Research
& Extension Center and Farm Advisor; University of
California Cooperative Extension
Steven D. Wright; Farm Advisor; University of
California Cooperative Extension Tulare and Kings
Counties
William R. Horwath, Ph.D.; Professor of Soil
Biogeochemistry and James G. Boswell Endowed Chair in
Soil Science; Department of Land, Air and Water
Resources, University of California, Davis
Support:
Moradi A. Barzin, Ph.D.; Senior Environmental
Scientist FREP, California Department of Food and
Agriculture
Amadou Ba, Ph.D.; Branch Chief Feed,
Fertilizer, and Livestock Drugs Regulatory Services,
California Department of Food and Agriculture
Amrith Gunasekara, Ph.D.; Science Advisor to
the Secretary; California Department of Food and
Agriculture
Javascript is disabled on your browser.
For full functionality of this site it is necessary to enable
JavaScript. Follow this link for
instructions on how to enable JavaScript in your web browser.
Nitrogen is the most commonly limiting nutrient in barley
production. The deficiency manifests as an overall
yellowing of the leaves. Nitrogen is mobile in the plant,
so symptoms will begin with the older leaves while the
younger leaves may appear healthy. Nitrogen-deficient
plants are smaller and have fewer tillers [N28, N44].
Nitrogen deficient
barley plants. Older leaves die and form a thatch of dry
leaves around the base of the plants (photo provided by
the International
Plant Nutrition Institute).
Excessive N increases lodging, delays maturity, increases
severity of some diseases, pollutes groundwater, and
causes rainfed barley to deplete moisture too early in the
season [N5, N10, N28].
Excessive N applications can also increase grain protein
content and reduce plump kernel percentage of malting
barleys to unacceptable levels [N27,N32].
Residual soil nitrate and irrigation water nitrate
contribute to barley's N requirement. These tests are
especially important for fertilizing malt barley, as
excess N fertilization may increase grain protein content
to a level which reduces marketability [N34].
The residual soil nitrate level depends on a
number of factors related to soil properties,
weather and crop management (see Factors Affecting Soil Nitrate-N).
Therefore, the test needs to be carried out every year.
Sampling should be taken close to planting or in
spring before the first topdress N application. Due
to the variability of nitrate in the soil, care must
be taken to assure that the sample is representative
for the field (see Sampling Instructions).
Although barley roots may be 5 feet deep in the
absence of limiting layers [N20, N45], soil is generally sampled to a depth of two feet, in one-foot increments [N5, N11, N16].
Pounds of nitrate-N potentially available per acre
in each foot of soil can be estimated by multiplying
parts per million of nitrate-N by 4 [N5]. For example,
a nitrate-N concentration of 10 ppm in the top foot
of the profile corresponds to 40 lbs N/acre.
Soil samples can be sent to a laboratory or extracted and
analyzed on the farm. The soil nitrate quick test with colorimetric
test strips is highly correlated with the standard laboratory
technique and has been found to be a reliable estimate of current
soil N status. It is a tool that can help growers make more
informed decisions regarding N management. Interactive step-by-step
instructions on how to do a quick test and a web tool to interpret
the results can be found here.
When well water is used for irrigation, a
considerable amount of N may be applied with the
irrigation water. To convert nitrate-N concentration
in the water to lbs N/acre, ppm nitrate-N in the
water is multiplied by 0.226 and by the number of
acre-inches of water applied [N11].
For example, with 1 acre-inch of water containing 10
ppm nitrate-N, 2.26 lbs N are applied per acre.
The nutrient status of barley can be determined by
analyzing leaves or stems. For wheat, stem nitrate-N
concentrations were found to vary more between sites than
total plant N [N21].
Due to such site-specific differences, N fertilization
decisions should not be based on plant analyses alone.
Non-uniform fields are best divided into uniform areas
which are sampled separately. Atypical areas in a field
should be avoided (if small) or sampled separately. For
more information on sampling procedure see Plant Tissue Sampling.
For a representative sample, the top four leaves
from 50 to 100 randomly selected plants should be
sampled [N22].
Fresh tissue samples should be placed in open, clean
paper bags. The samples may be partially air-dried
or kept cool during shipment to the laboratory [N22].
To take a representative tissue sample, collect
20-40 stems from random plants . Cut off the roots
and plant tops, taking care that no soil or leaves
contaminate the sample. Send the bottom 1-2 inches
of the stems to the lab for analysis on the day that
they are collected [N28].
Wheat and barley are generally considered to have
the same critical levels; however, research in
Arizona suggests that lower levels may be
appropriate for irrigated malting barley [N31, N39].
The amount of N required by barley is often
estimated by multiplying the bushels of expected
yield by a factor determined in field trials. Little
research has been done in California to determine
yield-based recommendations. Recommendations based
on field trials in Arizona [N30,
N31], Western Oregon and Washington [N4, N16, N17, N41],
the Great Plains [N18],
Colorado [N11]
and Idaho [N5, N38]
yield an average recommendation of 1.2-1.5 lbs
available N per bushel (50-63 lbs N/ton) of expected
yield for malting barley and 1.7-2.0 lbs available N
per bushel (70 - 83 lbs N/ton) for feed barley.
To determine the seasonal fertilizer application
rate, the available N needs to be adjusted as
follows:
Residual soil nitrate or nitrate in the
irrigation water is subtracted (see Soil Testing).
If straw or corn stubble was returned to soil
directly before barley, an extra 10-15 lbs N/ ton
of residue is recommended, to assist with
breakdown [N5, N31].
If barley follows a legume like peas or beans,
a reduction of 30-40 lbs N/acre can be made. For
California rainfed small grains, Munier and
coworkers [N28]
recommend as little as 10-20 lbs N/acre (applied
at sowing) for a crop following a legume fallow.
If barley follows alfalfa a reduction of about
60 lbs N /acre is commonly recommended, depending
on stand density [N5,
N11, N16, N18].
Soil N which may potentially be released from
organic matter is often ignored as California
soils tend to be low in organic matter [N29]. Malting
barley growers on higher organic matter soils,
such as those around the Tulelake Basin [N34] should
consult their local farm farm advisor.
Optimal barley yields in California have been
obtained with N fertilizer application rates of
50-120 lbs N/acre [N28].
While high yields are produced with 50-80 lbs N/acre
in the Intermountain area, 120-150 lbs N/acre are
generally applied in the San Joaquin Valley to
achieve top yields (R. Wilson and S. Wright,
personal communication).
Splitting applications generally increases N use
efficiency and allows rainfed barley growers to
adjust total rates in drier years when yield is
lower than expected [N7].
In California, split applications are especially
recommended for barley grown on soils with claypans
or hardpans, soils prone to waterlogging, and
shallow or coarse-textured soils [N28].
Barley planted in late fall takes up little N until
late January or early February [N28].
In general, barley plants generally take up less
than 50 lbs/acre before stem elongation (jointing
stage) takes place [N12].
However, since tillers and heads are formed in early
growth stages, early-season deficiencies will
strongly affect yield [N2,
N28]. It is necessary to provide
sufficient N for early growth while avoiding excess
application that could lead to leaching losses with
winter rains, lodging and increase the risk of
freeze damage [N1, N2].
No preplant fertilizer is advised for irrigated
barley in many states; rather, a starter application
of 15-30 lbs N/acre is recommended, with the rest of
the requirement applied in spring [N1, N5, N27, N31, N46].
For California, Munier and coworkers [N28] recommend
that 1/2 to 2/3 of the total N requirement be
applied at sowing and the remainder as topdress,
with half applied at sowing for very sandy or
gravelly soils. In fields with a history of manure
and lagoon water applications, the barley crop
probably has sufficient N until early spring and
preplant and starter applications are not necessary
[N28].
Preplant fertilizers may be broadcast, injected,
banded or placed in irrigation water [N28]. Dry
fertilizer, especially urea, needs to be
incorporated or watered in as soon as possible to
avoid volatilization losses [N23].
Subsurface banding is best if soil nitrate levels
are low or volatilization potentials are high; i.e.
high pH or soils with crop residues on the surface [N23, N27].
Anhydrous ammonium and aqua ammonia must be
injected 6 to 8 inches deep in loamy soils and 8-10
inches deep in sandy soils to avoid losses of
gaseous ammonia [N3, N37].
When properly managed, no quality or yield
differences have been observed between different
fertilizers [N27].
Fertilizer choice depends on the weather (current
and forecast), and fertilizer costs [N28]. Urea is
inexpensive, high analysis and nitrifies less
quickly than ammonium fertilizers. However, ammonium
and especially urea-based fertilizers are prone to
volatilization and should only be applied if they
can be incorporated or if a rain or irrigation event
of at least 1/2 inch is expected within a few days
after application [N23,
N28].
Urease inhibitors and slow-release coatings may
reduce N losses from fall-applied urea and increase
N use efficiency [N27].
They should, however, be avoided for rainfed barley
because their rate of release depends on soil
moisture and temperature and they risk providing
insufficient N at times of peak uptake and supplying
too much late in the season when N availability can
increase malting barley protein to unacceptable
levels [N27].
In shallow or coarse soils, nitrate-based
fertilizers are not recommended because of their
leaching potential [N27].
Nitrogen applied in fall is prone to leaching with
winter rains. Therefore, preplant N applications to
barley are best done as close to sowing as possible,
to reduce the time between application and plant
uptake. This is especially important under
conservation tillage and when there are other
residues in the field whose decomposition may
compete with barley for soil N [N15, N25].
No more than 30 lbs N+K2O should be
applied directly with the seed to avoid seedling
injury [N31, N33].
Before stem elongation (jointing stage) takes place,
barley plants generally take up less than 50
lbs/acre [N12].
When the total N requirements until spring are not
met by the starter fertilizer and the residual soil
nitrate, the difference should be applied preplant.
Trials on rainfed wheat in Oregon and Washington
have showed that subsurface banding is more
efficient than broadcasting, particularly for spring
grains [N33, N42, N43].
A band 2 inches below and to the side of the seed is
generally recommended, although in coarse-textured
soils the distance may be increased [N43]. No-till
grains may especially benefit from deep banding,
because it reduces the weed competition and residue
tie-up associated with surface broadcasting [N43]. Broadcast
urea is also more in danger of volatilizing where
residues are on the surface, because they limit
urea's contact with soil [N23].
Small grains are tolerant of close placement,
except when soils are dry at seeding time [N41]. In moist
soils P and small amounts of N and K can be drilled
with the seed [N24];
this is an efficient means in very cold, wet soils
where root development is likely to be limited.
Banding of starter N and P together has been shown
to increase plant P uptake [N35].
A low N, high P fertilizer such as monoammonium
phosphate (MAP) is recommended.
Urea, anhydrous ammonia, ammonium thiosulfate and
diammonium phosphate (DAP) can be used, but should
not be placed with the seed because these materials
may release free ammonia which is toxic to young
seedling roots [N18, N19,
N33, N36].
In California, Munier and coworkers [N28] recommend
that 1/2 to 2/3 of the total N requirement be
applied at sowing and the remainder as topdress,
with half applied at sowing for very sandy or
gravelly soils. One or two applications of 30-50 lbs
N/acre are recommended, depending on the winter
rainfall and N status of the plants [N28].
To minimize volatilization losses, broadcast urea
and ammonium applications should be timed so that
they are followed within 1-2 days by irrigation or a
rainfall event of at least 0.5 inches within a few
days [N23, N28].
Soil moisture should also be taken into account as
applications to very dry soil can decrease yields,
possibly by damaging seedling roots [N15].
Liquid N fertilizer may also be injected into
sprinkler systems and applied with the irrigation
water. However, topdress applications of liquid
fertilizer to established barley should be less than
40 lbs N/acre to prevent leaf burn [N27].
When well-managed and when there are no severe
deficiencies, different fertilizer types do not
differ in their effects on grain yield or quality [N27]. The choice
of fertilizer depends on the current and forecasted
weather conditions, the urgency of the deficiency
and fertilizer costs. Urea (46-0- 0) is inexpensive,
high analysis, and is commonly used if it can be
washed into the soil within a few days by irrigation
or rainfall [N28].
If the crop is severely N-deficient fertilizers
containing nitrate such as UAN or ammonium nitrate
are recommended, because nitrate moves easily in
soil, is less likely than ammonium to be immobilized
and is immediately available to plant roots after
the first irrigation [N28,
N31].
Ammonium sulfate may be a good choice if sulfur is
also required, but it is more expensive than urea [N28].
In California, little N uptake occurs in winter if
the crop is sown in late fall and has not grown much
before the cold weather. Uptake starts to occur in
late January and early February, rises through the
spring, and starts to decrease after heading [N28, N31].
Nitrogen uptake is highest during stem elongation
stage, which is also the time when heads are formed
[N1, N46]. Thus,
N applications made during the tillering stage, as
long as they are followed by rain or irrigation, are
the most effective for achieving high grain yields [N2].
Applications at the booting stage are less
effective, and at heading or later will have little
effect on grain yield [N28].
Late applications at booting or later may also
increase the risk of lodging (S. Wright, personal
communication). Furthermore, growers of malting
barley should use late applications with caution, as
they may increase the protein concentration and
decrease kernel plumpness [N7].
Response to foliar N may be quicker than to water- or
soil-applied N [N13],
but it is more expensive and may damage the leaves if
applied at rates greater than 10-20 lbs N/acre [N31]. Foote and
Batchelder [N15] found
that soil topdressed ammonium nitrate gave higher yields
than equivalent rates of foliar-sprayed urea on rainfed
spring barley in Oregon.
A study on rainfed spring barley in the Willamette
Valley found urea sprays to 6-inch tall barley to be
more effective for increasing yields than sprays at
12 inches or early heading [N15].
Risk of leaf burn may also be lower when foliar
applications are made earlier in the year, while
temperatures are cooler [N23].
Foliar N sprays after anthesis can increase grain
protein [N9, N41].
However, when soil N availability is sufficient,
foliar applications may have little effect on
protein concentration [N6].
Midday applications are more likely to result in
leaf burn than applications made in the early
morning or late afternoon; however, leaf burn is
also associated with applications made while the dew
is still on the crop [N13].
Any water-soluble fertilizer may be used but the
rates will vary. Urea is a common choice, since it
is rapidly and efficiently absorbed and is less
likely to cause leaf burn than ammonium sulfate or
ammonium nitrate [N13,
N14]. Urea-ammonium nitrate (UAN) is
also effective [N41].
Malakondaiah and coworkers [N26]
reported the best results from a 1.5%-2.2% urea
solution.
Phosphorus is especially important for seedling vigor,
root development and early-season growth. It also has a
regulating role in tillering [P15].
Commonly the only early symptoms are stunting, slow early
growth and a lack of tillering, making P deficiencies
difficult to see [P4, P15].
Sometimes purpling is observed, starting on the older
leaves and advancing to younger as the deficiency becomes
severe [P25].
Phosphorus deficiencies are most likely in conditions of
slow root development, such as very cold or waterlogged
soils. In California barley production, P deficiency is
most common on shallow uplands, i.e., terrace and foothill
soils [P15], and
following rice [P2].
Soil samples are generally taken in fall or spring
from the top foot of the profile where root density
is highest [P18].
However, barley can access nutrients and water below
the top foot of the profile. While the root density
is highest in the top two feet of the profile, some
roots may reach to a depth of 5 feet [P10, P26] . A
total of 15-20 cores should be taken from the field;
a sufficient sample is especially important in
fields where P has been banded previously [P6]. See Soil Test Sampling for sampling
instructions.
To make accurate P fertilization decisions, soil
test values are best combined with tissue P
concentrations and P budgets (see Preplant
Application Rate).
In California, the available soil P is generally
determined on sodium bicarbonate extracts (Olsen-P
test). This test should be limited to soils with a
pH between 5.5 and 8.5 containing less than 3% of
organic matter. For soil outside this range, water
or calcium chloride extracts may be more reliable [P18]. For more
information contact your local farm advisor.
A yield response is likely if barley is grown on a
soil with test P below 6 ppm and unlikely if it is
greater than 15 ppm Olsen-P [P6,
P15, P27]. Response on soils with
values from 6-15 ppm is variable; positive responses
seem to be associated with high yield potentials,
late seeding dates and the presence of root diseases
that limit plant growth [P27].
Tissue P values should be used to make site-specific
assessments.
Interpretation of P and K soil test levels in the
top foot of the soil profile [P15,
P18]. 1) ppm Olsen-P 2) ppm ammonium acetate extractable K
Since P fertilizer can interact with free lime in
the soil, Stark and Brown [P21]
recommend using a critical value of 20 ppm if free
lime exceeds 10%.
In cold, wet conditions a response may be seen to
seed-placed P even in soils with adequate P [P12].
Barley grown after rice usually responds to P
fertilizer, even if the soil test suggests adequate
P is available [P2].
The nutrient status of barley can be determined by
analyzing leaves or stems. Site-specific factors may
affect plant nutrient concentrations. For this reason,
fertilization decisions should not be based on plant
analyses alone.
Non-uniform fields are best divided into uniform areas
which are sampled separately. Atypical areas in a field
should be avoided (if small) or sampled separately. For
more information on sampling procedure see Plant Tissue Sampling.
For a representative sample, the top four leaves
from 50 to 100 randomly selected plants should be
sampled [P11].
Fresh tissue samples should be placed in open, clean
paper bags. The samples may be partially air-dried
or kept cool during shipment to the laboratory [P11].
For a representative sample, 20 to 40 stems should
be collected at random from a field. The bottom 1 to
2 inches of each stem are used for analysis and the
roots and plant tops are cut off. The sample should
be sent to the lab the day it has been collected.
For an accurate result, the sample needs to be free
of soil and old leaves [P15].
To maintain P availability at an optimal level in
the long term, the P removed at harvest may be
replaced. Approximately 0.4-0.62 lbs P2O5
are taken off the field for each bushel of grain
harvested. A ton of straw contains approximately
3-4.2 lbs P2O5[P20, P22]. For
example, if a barley field yields 80 bu of grains
per acre (3840 lbs/acre) and the harvest index is
0.5, 32- 50 lbs P2O5 /acre are
removed with the grains and 6-8 lbs/acre with the
straw. Higher rates may be required for soils that
test in the deficient range, particularly in acid or
alkaline soils in which P is less available.
In California, Munier and coworkers recommend
adding 30-40 lbs P2O5/acre for
irrigated barley, and 20-30 lbs for dryland [P15]. If using
an ammonium-containing fertilizer such as MAP, no
more than 25-30 lbs N/acre should be drilled with
the seed. If P is broadcast rates should be doubled
[P6, P8, P15, P16].
Rates may be higher in acid or alkaline soils, in
which P is less available.
The amount of fertilizer that can be band-applied
safely at planting depends on its N and K content
(see Starter N).
If soil is P deficient and a heavy application of P
fertilizer is needed to raise the general P level,
broadcasting and incorporating P prior to seeding
can be effective as long as the pH is neutral [P20]. Since P
is immobile in soil, broadcast P should be
incorporated before planting to ensure it goes into
the root zone [P6].
Broadcasting P is not recommended on acid, alkaline
or P-fixing soils [P3].
Banding is considered more efficient than
broadcasting [P6, P8].
Bands should be 1.5 to 2 inches below and to the
side of the seed for good root contact. Longer
distances may be required for coarse-textured soils
to avoid seedling injury when P is applied together
with N [P24].
Uptake of P is improved if it is banded with N.
Starter fertilizer may also be drilled directly
with the seed [P12, P15].
This is particularly recommended in cold, wet
conditions in which both root growth and P diffusion
in the soil are limited [P20]
or in acid, alkaline and calcareous soils in which P
is relatively unavailable [P15].
If an ammonium-containing fertilizer such as
monoammonium phosphate (MAP) is used, no more than
25-30 lbs N per acre should be drilled with the seed
[P15].
A number of granular and liquid P fertilizers are
available for preplant and starter applications.
Fact sheets of the most common fertilizers can be
found on the web site of the International
Plant Nutrition Institute.
The presence of N in the fertilizer band improves P
uptake, but too much N fertilizer may damage the
seedling. Therefore low ammonium, high P fertilizers
such as monoammonium phosphate (MAP) are recommended
for starter fertilizers. MAP is preferable to
diammonium phosphate (DAP), which has a higher salt
index and gives off free ammonia, which is toxic to
seedlings [P15, P20].
When barley is grown in the first year or two after
flooded rice P is often deficient. Research by
Brandon and Mikkelsen on California rice soils shows
that MAP is more effectively used by barley grown
after rice than triple superphosphate (TSP),
probably due to the presence of ammonium in the
fertilizer band [P2].
When smaller application rates are required, all P
may be applied as a starter. When larger quantities
are needed, it may be more practical to apply a
small amount as a starter and broadcast the rest
preplant.
Preplant P fertilizer is best applied before a
tillage operation when broadcast. However, the time
of application is not as crucial as it is with N
because P is immobile in the soil and does not
leach.
All P is normally applied prior to planting, as P
deficiencies in early growth have the most serious
consequences for yield [P9]
and P is immobile in the soil and does not leach.
Several studies have demonstrated increased yields after
P foliar sprays to P-deficient barley [P1, P13, P17].
However, increases have not been found with sufficient
soil P fertilization [P13,
P23].
Too heavy an application of a given foliar P compound can
cause leaf burn, which may reduce yields if it is severe [P7]. A general plant
tolerance level of 4-6 lbs of MAP and DAP per 100 gal
water and 3-5 lbs of phosphoric acid per 100 gal water is
advised for repeated foliar sprays [P14].
Potassium is essential for barley growth and development,
aiding in the development of strong roots and stem,
decreased lodging and resistance to winter kill and root
diseases [K16].
Deficiency symptoms begin on the older leaves, although
the whole plant may be affected. Early symptoms include
chlorotic leaf tips and margins. As deficiency becomes
more severe necrosis appears as a speckling along the
length of the leaf and spreads to the tips and margins. An
"arrow" of green tissue remains from the base upward to
the center of the leaf. The death of older leaves is
common [K15, K16, K21].
Severe K deficiency on
a sandy soil in early spring (right). Barley on the left
received a low amount of starter fertilizer (photo
provided by the International Plant Nutrition Institute).
Soil samples are generally taken in fall or spring
from the top foot of the profile where root density
is highest [K17].
However, barley can access nutrients and water below
the top foot of the profile. While the root density
is highest in the top two feet of the profile, some
roots may reach to a depth of 5 feet [K10, K22]. A
total of 15-20 cores should be taken from the field;
a sufficient sample is especially important in
fields where P has been banded previously [K6]. See Soil Test Sampling for sampling
instructions.
To make accurate K fertilization decisions, soil
test values are best combined with tissue K
concentrations and K budgets (see Preplant
Application Rate).
Plant available K is determined by extracting the
soil samples with an ammonium acetate solution [K17].
Yield responses to K are very rare in California
and are expected only on the most deficient soils,
with an ammonium acetate-extractable K of less than
60 ppm [K16].
In Washington and Oregon, on soils with low latent
reserves of K a critical value of 100 ppm is used [N19]. Where
soils are in the medium range, fertilizer may be
added to replace K removed in harvest. If barley is
grown in rotation with other crops that receive K,
no fertilization may be necessary [K3].
Interpretation of P and K soil test levels in the
top foot of the soil profile [K16,
K17]. 1) ppm Olsen-P 2) ppm ammonium acetate extractable K
The nutrient status of barley can be determined by
analyzing leaves or stems. Site-specific factors may
affect plant nutrient concentrations. For this reason,
fertilization decisions should not be based on plant
analyses alone.
Non-uniform fields are best divided into uniform areas
which are sampled separately. Atypical areas in a field
should be avoided (if small) or sampled separately. For
more information on sampling procedure see Plant Tissue Sampling.
For a representative sample, the top four leaves
from 50 to 100 randomly selected plants should be
sampled [K12].
Fresh tissue samples should be placed in open, clean
paper bags. The samples may be partially air-dried
or kept cool during shipment to the laboratory [K12].
For a representative sample, 20 to 40 stems should
be collected at random from a field. The bottom 1 to
2 inches of each stem are used for analysis and the
roots and plant tops are cut off. The sample should
be sent to the lab the day it has been collected.
For an accurate result, the sample needs to be free
of soil and old leaves [K16].
In general, in California yield responses to K
fertilization are unusual in small grains unless the
soil is very deficient [K16].
To maintain K availability at an optimal level in
the long term, the K removed at harvest may be
replaced. Approximately 0.3-0.35 lbs K2O
are taken off the field for each bushel of grain
harvested. A ton of straw contains approximately 40
lbs K2O [K18,
K19]. For example, if a barley field
yields 80 bu of grains per acre (3840 lbs/acre) and
the harvest index is 0.5, 24-28 lbs K2O/acre
are removed with the grains and 75-80 lbs/acre with
the straw. However, unless the soils are K deficient
or fix K, K applications may not have economic
benefits. Contact your local farm advisor for more
information.
Generally K is broadcast and incorporated prior to
planting. Banding low rates of K as starter
fertilizer at planting may increase yields [K13]; however,
the benefit gained from banding is likely to be
small in soils with medium and high soil test K.
Potassium is relatively immobile in the soil and
needed in high amounts early in the growing season,
so it is best to apply at or immediately prior to
seeding. It is not usually topdressed [K14].
Potassium chloride (KCl), potassium sulfate (K2SO4),
and potassium magnesium sulfate (K2SO4*
2MgSO4) are common K fertilizers. They
all contain readily available K. Choice of
fertilizer may be made based on price and whether
the application of chloride, sulfate or magnesium is
beneficial.
Yield response to KCl applications has been seen
even in high K-testing soils, due to the beneficial
impact of chloride fertilization, which may
decreased root rot incidence and spot blotch
symptoms on the flag leaves [K8,
K20].
Potassium is seldom included in a starter fertilizer. If
a starter blend containing K is used, it needs to be
applied with care, as K and ammonium may damage seedling
roots. Even though barley is relatively salt tolerant the
total N plus K2O should not exceed 30 lbs/acre,
unless a wide opener is used [K14].
If larger rates of K are needed, they may either be
broadcast prior to planting or banded at least one inch
away [K14].
In K-fixing soils, such as occur on the east side of the
San Joaquin valley, banding or placement with the seed is
the most efficient way to apply K. For more information,
see K Fixation in the San Joaquin Valley.
Starter K may also be beneficial in cool, wet no-till
soils even if soil test K is high, as soil K may be less
available to the seed [K11].
Potassium is relatively immobile in the soil and can be
applied at or immediately prior to seeding. It is not
usually topdressed [K14].
On deep sandy soils with a high leaching potential, a
split application may be considered, with half of the
total rate applied prior to planting and half just before
stem elongation [K5].
Increases in yield and disease resistance have been seen
on K-deficient, sandy soils in Australia in response to K
applications 8 weeks after seeding [K2].
Little research has been done to explore the effects of
foliar K on barley. Potassium is required in much larger
amounts than what can be applied with foliar fertilizers [K7]. Therefore, foliar
K applications can at best supplement soil applied K, but
not replace it.
Some studies with wheat suggest that foliar K
applications can reduce yield losses caused by salinity or
drought [K1, K23].
Daniel Geisseler, Ph.D.; UCCE Specialist in Nutrient
Management; Department of Land, Air and Water Resources,
University of California, Davis
Patricia Lazicki; Department of Land, Air and
Water Resources, University of California, Davis
Reviewers:
Rob Wilson; Director Intermountain Research
& Extension Center and Farm Advisor; University of
California Cooperative Extension
Steven D. Wright; Farm Advisor; University of
California Cooperative Extension Tulare and Kings
Counties
William R. Horwath, Ph.D.; Professor of Soil
Biogeochemistry and James G. Boswell Endowed Chair in
Soil Science; Department of Land, Air and Water
Resources, University of California, Davis
Support:
Moradi A. Barzin, Ph.D.; Senior Environmental
Scientist FREP, California Department of Food and
Agriculture
Amadou Ba, Ph.D.; Branch Chief Feed,
Fertilizer, and Livestock Drugs Regulatory Services,
California Department of Food and Agriculture
Amrith Gunasekara, Ph.D.; Science Advisor to
the Secretary; California Department of Food and
Agriculture
Baethgen, W.E., Christianson, C.B., Lamothe, A.G., 1995.
Nitrogen fertilizer effects on growth, grain yield and yield
components of malting barley. Field Crops Research 43,
87-99.
Blue, W.G., Eno, C.F., 1954. Distribution and retention of
anhydrous ammonia in sandy soils. Soil Science Society of
America Proceedings 18, 420-424.
Brauen, S.E., Turner, D.O., Halvorson, A.R., 1976. Fertilizer
guide: Spring wheat, barley and oats for western
Washington. FG-48 (Rev). Washington State University.
Delogu, G., Cattivelli,L., Pecchioni, N., De Falcis, D.,
Maggiore, T., Stanca, A.M., 1998. Uptake and agronomic
efficiency of nitrogen in winter barley and winter wheat.
European Journal of Agronomy 9, 11-20.
Fageria, N.K., Barbosa Filho, M.P., Moreira, A.,
Guimarães, C.M., 2009. Foliar fertilization of crop plants.
Journal of Plant Nutrition 32, 1044-1064.
Foote, W.H., Batchelder, F.C., 1953. Effect of different
rates and times of application of nitrogen fertilizers on
the yield of Hannchen barley. Agronomy Journal 45, 532-535.
Gregory, P.J., Tennant, D., Belford, R.K., 1992. Root and
shoot growth, and water and light use efficiency of barley
and wheat crops grown on a shallow duplex soil in a
Mediterranean-type environment. Australian Journal of
Agricultural Research 43, 555-573.
Hawe, W.P., Cassman, K.G., Fulton, A., Jackson, L.F.,
1989. Evaluation of tissue nitrogen tests as a prognostic
tool for irrigated wheat production. Journal of Fertilizer
Issues 6, 89-99.
Jones Jr., J.B., 1998. Field sampling procedures for
conducting a plant analysis. In: Kalra, Y.P. (Ed.). Handbook
of Reference Methods for Plant Analysis. CRC Press, Boca
Raton. pp. 25-35.
Malakondaiah, N., Safaya, N.M., Wali, M.K., 1981.
Responses of alfalfa and barley to foliar application of N
and P on a coal mine spoil. Plant & Soil 59, 441-453.
Munier, D., Kearney, T., Pettygrove, G.S., Brittan, K.,
Mathews, M., Jackson, L., 2006. Fertilization of small grains. In: UC
ANR (Ed.). Small Grain Production Manual. ANR Publication
8208.
Petrie, S., Hayes, P., Rhinhart, K., Blake, N., Kling, J.,
Corey, A., 2003. Fertilizer management for winter malting
barley. Agricultural Experiment Station Oregon State
University Special Report 1047.
Sangakkara, U.R., Cho, C.M., 1987. Effect of NH4+
nitrogen on phosphorus uptake by canola, lentils, soybeans
and wheat. Journal of Agronomy and Crop Science 159,
199-201.
Stanley, F.A., Smith, G.E., 1956. Effect of soil moisture
and depth of application on retention of anhydrous ammonia.
Soil Science Society of America Proceedings 20, 557-561.
Stark, J.C., Brown, B.D., 2003. Nutrient management. In: Robertson,
L.D., Stark, J.C. (Ed.). Idaho Spring Barley Production
Guide. University of Idaho Bulletin 742, 22-26.
Thompson, T.L., Ottman, M.J., Riley-Saxton, E., 2004.
Basal stem nitrate tests for irrigated malting barley.
Agronomy Journal 96, 516-524.
Turley, R.H., Ching, T.M., 1986. Storage protein
accumulation in 'Scio' barley seed as affected by late
foliar applications of nitrogen. Crop Science 26,778-782.
Turner, D.O., Brauen, S.E., Halvorson, A.R., 1976. Fertilizer guide:
winter wheat and barley for western Washington. FG-17 (Rev).
Washington State University Cooperative Extension Service.
Benbella, M., Paulsen, G.M., 1998. Efficacy of treatments
for delaying senescence of wheat leaves: II. Senescence and
grain ield under field conditions. Agronomy Journal 90,
332-338.
Brandon, D.M., Mikkelsen, D.S., 1979. Phosphorus
transformations in alternately flooded California soils: I.
Cause of plant phosphorus deficiency in rice rotation crops
and correctional methods. Soil Science of America Journal
43, 989-994.
Grant, C.A., Flaten, D.N., Tomasiewicz, D.J., Sheppard,
S.C., 2000. The importance of early season phosphorus
nutrition. Canadian Journal of Plant Science 81, 211-224.
Gregory, P.J., Tennant, D., Belford, R.K., 1992. Root and
shoot growth, and water and light use efficiency of barley
and wheat crops grown on a shallow duplex soil in a
Mediterranean-type environment. Australian Journal of
Agricultural Research 43, 555-573.
Jones Jr., J.B., 1998. Field sampling procedures for
conducting a plant analysis. In: Kalra, Y.P. (Ed.). Handbook
of Reference Methods for Plant Analysis. CRC Press, Boca
Raton. pp. 25-35.
Malakondaiah, N., Safaya, N.M., Wali, M.K., 1981.
Responses of alfalfa and barley to foliar application of N
and P on a coal mine spoil. Plant & Soil 59, 441-453.
Munier, D., Kearney, T., Pettygrove, G.S., Brittan, K.,
Mathews, M., Jackson, L., 2006. Fertilization of small grains. In: UC
ANR (Ed.). Small Grain Production Manual. ANR Publication
8208.
Qaseem, S.M., Afridi, M.M.R.K., Samiullah, 1978. Effect of
leaf-applied phosphorus on the yield characteristics of ten
barley varieties. Indian J. Agric. Sci. 48,215-217.
Reisenauer, H.M., Quick, J., Voss, R.E., 1976. Soil test
interpretive guides. In: Reisenauer, H.M. (Ed.). Soil and
Plant-Tissue Testing in California. University of California
Cooperative Extension Bulletin 1879. pp. 38-40.
Stark, J.C., Brown, B.D., 2003. Nutrient management. In: Robertson,
L.D., Stark, J.C. (Ed.). Idaho Spring Barley Production
Guide. University of Idaho Bulletin 742, 22-26.
Tarkalson, David D., Brown, B., Kok, Hans, Bjorneberg,
D.L., 2009. Irrigated small-grain residue management effects
on soil chemical and physical properties and nutrient
cycling. Soil Science 174, 303- 311.
Thomason, W.E., Phillips, S.B., Warren, J.A., Alley, M.M.,
2012. Winter hulless barley response to nitrogen rate and
timing and foliar phosphorus. Journal of Plant Nutrition
35,225-234.
Brennan, R.F., Jayasena, K.W., 2010. Increasing
applications of potassium fertilizer to barley crops grown
on deficient sandy soils increased grain yields while
decreasing some foliar diseases. Australian Journal of
Agricultural Research 58, 680-689.
California Plant Health Association, 2002. Western
Fertilizer Handbook 9th edition. Interstate
Publishers, Inc.
Crozier, C., Heiniger, R., Weisz, R., 2013. Nutrient management for small grains. In
Weisz, R. (Ed.). Small Grain Production Guide. North
Carolina State University.
Gregory, P.J., Tennant, D., Belford, R.K., 1992. Root and
shoot growth, and water and light use efficiency of barley
and wheat crops grown on a shallow duplex soil in a
Mediterranean-type environment. Australian Journal of
Agricultural Research 43, 555-573.
Jackson, G.D., Kushnak, G.D., Benson, A.N., Skogley, E.O.,
Lund, R.E., 1991. Potassium response in no- till small grain
production. Journal of Fertilizer Issues 8, 89-92.
Jones Jr., J.B., 1998. Field sampling procedures for
conducting a plant analysis. In: Kalra, Y.P. (Ed.). Handbook
of Reference Methods for Plant Analysis. CRC Press, Boca
Raton. pp. 25-35.
Mullison, W.R., Mullison, E., 1942. Growth responses of
barley seedlings in relation to potassium and sodium
nutrition. Plant Physiology 17, 632-644.
Munier, D., Kearney, T., Pettygrove, G.S., Brittan, K.,
Mathews, M., Jackson, L., 2006. Fertilization of small grains. In: UC
ANR (Ed.). Small Grain Production Manual. ANR Publication
8208.
Reisenauer, H.M., Quick, J., Voss, R.E., 1976. Soil test
interpretive guides. In: Reisenauer, H.M. (Ed.). Soil and
Plant-Tissue Testing in California. University of California
Cooperative Extension Bulletin 1879. pp. 38-40.
Tarkalson, David D., Brown, B., Kok, Hans, Bjorneberg,
D.L., 2009. Irrigated small-grain residue management effects
on soil chemical and physical properties and nutrient
cycling. Soil Science 174, 303- 311.
Timm, C.A., Goos, R.J., Johnson, E., Sobolik, F.J., Stack,
R.W., 1986. Effect of potassium fertilizers on malting
barley infected with common root rot. Agronomy Journal 78,
197-200.
Wallace, T., 1943. The diagnosis of mineral deficiencies
in plants by visual symptoms. His Majesty’s Stationery
Office, London.
Weaver, J.E., 1926. Root Development of Field Crops.
McGraw-Hill Book Company, Inc. New York.
Zheng, Y., Xianbin, X., Simmons, M., Zhang, C., Gao, F.,
Li, Z., 2010. Responses of physiological parameters, grain
yield and grain quality to foliar applications of potassium
nitrate in two contrasting winter wheat cultivars under
salinity stress. Journal of Plant Nutrition and Soil Science
173, 444-452.