Nitrogen Nitrogen Uptake of Uptake of pp

Corn, Cereal Corn, Cereal Forage and Forage and Forage and Forage and

Alfalfa Alfalfa

Marsha Campbell MathewsFarm Advisor University of California CE Stanislaus County

David CrohnWaste Management Specialist University of California Riverside

Central Valley Regional Water Quality Control Board Water Quality Control Board

Dairy Waste Discharge RequirementDairy Waste Discharge Requirement

Total N applied Total N applied 1.4 to 1.65% of crop uptake.

This is hard.

Crop Nitrogen Uptake

Essential for designing effective nitrogen budgets that provide the crop the g p p

nitrogen it needs

in the right formin the correct amountin the correct amountat the proper time

Calculating total removal

Silage Total Silage Total Silage Total Silage Total RemovalRemoval

Lbs dry matter/A x % N 

Lbs dry matter/A x % protein/6.25 

Tons/A @ 70% x % protein x .96

30 Tons/A x 8 5% x 96 = 245 lbs N/acre30 Tons/A x 8.5% x .96 = 245 lbs N/acre

Calculating total removal

Hay Total Hay Total Hay Total Hay Total RemovalRemoval

Lbs dry matter/A x % N 

Lbs dry matter/A x % protein/6.25 

Tons/A @ 70% x % protein x 2.88

Nit Nitrogen Uptake Uptake

bybySilage gCorn

When does corn need nitrogenWhen does corn need nitrogen??Original work by Hanaway, 1962

(How a corn plant develops)

gg

(How a corn plant develops)

Redone with modern hybrids Sh F i t lSheppers, Francis, et al

Staygreen hybrids continue to take up & use N

R. D. Meyer (UCCE)4 yrs in Merced Countyy y

J. Mitchell, Mathews, Crohn (UCCE)3 yrs Stanislaus County3 yrs Stanislaus County

Nitrogen Uptake of Grain Corn

Growth stage % total uptake Growth stage % total uptake

6 leaf 5-10%

12 l f 30 35% 12 leaf 30-35%

18 leaf 70-75%

Tassel/silk 75-80%

Blister 80-85%

Dough 100%

Based on classic work by Hanaway, 1962

5 leaves8 leaves

12 leaves Early tassel

14

y 12108

e p

er

da

y

642p

er

ac

re

0-2-4L

bs

N p

4 leav

es

Full

tass

el

8 leav

es

12

leav

es

Bliste

r ea

r

Full

dent

silking

full dentfull dent

blister ear14

12

y

10

8

6e p

er

da

y

6

4

2

pe

r a

cre

0-2-4L

bs

N p

4 leav

es

Full

tass

el

8 leav

es

12 lea

ves

Bliste

r ea

r

Full

dent

Nitrogen Uptake of 30 Ton Corn Silage Crop

Growth Stage

Lbs/acre N in tops

% total uptake

0 to 4 leaf 9 4%

4 to 8 leaf 14 9%

8 to 12 leaf 36 24%

12 leaf to tassel 102 66% 12 leaf to tassel 102 66%

Emergence to tassel 161 lbs total

Based on paper by Karlen,et al

Nitrogen Uptake of 30 Ton Corn Silage Crop

Lbs/ac N % total

Nitrogen Uptake of 30 Ton Corn Silage Crop

Growth Stage in tops uptake

Silking 12 Silking -12

Blister 13 66%

Early dent 83 100% Early dent 83 100%

Mature .6

Silking to harvest 97 Emergence to harvest 246

Based on paper by Karlen,et al

Merced County Corn N UptakeMerced County Corn N Uptake 19981998--20002000

Corn N uptake by GDU Hilmar CACorn N uptake by GDU Hilmar CACorn N uptake by GDU Hilmar, CAR. D. Meyer, M. C. Mathews, T. Harter

400450

lkin

g

Corn N uptake by GDU Hilmar, CAR. D. Meyer, M. C. Mathews, T. Harter

400450

lkin

g % N uptake

Grain corn will remobilize N 250300350

ke, l

bs/A 33.4* RB98

29.8* RB9931.2* RB0041 6* B 98

sil

250300350

ke, l

bs/A 33.4* RB98

29.8* RB9931.2* RB0041 6* B 98

sil p

at silk(estimated)

69%65%Grain corn will remobilize N

& K from lower leaves & stalk into grain50

100150200

N u

ptak 41.6* B 98

33.3* B 9935.7* B 00

*T/A @ 70% Moisture50100150200

N u

ptak 41.6* B 98

33.3* B 9935.7* B 00

*T/A @ 70% Moisture

79%60%68%52%g

050

0 1000 2000 3000GDU

050

0 1000 2000 3000GDU

Avg 68%

Corn N uptake

Grain: 80% before tassel/silkingg

Silage:g1/3 after tassel/silking

Potassium uptake for corn is similar to nitrogen in

amount & timing

Nitrogen Nitrogen Uptake Uptake

byyCereal Forage

Cereal Forage

•Plantings from early October to December

•Harvest at different growth stagesg g

•Many types with vastly different growth habits

•Different nitrogen contents

10 tons @ 8% protein10 tons @ 8% protein = 80 lbs N/acre

vs20 tons @ 17% protein

= 340 lbs N/acre

Most nitrogen uptake work on cereals focuses on the period from flowering to grain fillon the period from flowering to grain fill

1997 to 20021997 to 2002Clipping studies with multiple locations,

varieties, planting dates.Cut about every 10 days

Massive amounts of dataN must be sufficient at

all timesall timesConsiderable variability

Massive amounts of dataN must have been

sufficient at all timessufficient at all timesConsiderable variability

David Crohn UCRDavid Crohn, UCR

Most parameters many growers p y ghave available already:

Planting DateHarvest DateHarvest DateExpected N removalMin Max Temperatures to

calculate Growing Degree Daysg g yVariety parameter for winter

growth/N uptakegrowth/N uptake

Winter Cereal Forage Nitrogen Uptake by Winter Cereal Forage Nitrogen Uptake by 

45

50

g g p yPeriod of Peak Nitrogen Uptake

45

50

g g p yPeriod of Peak Nitrogen Uptake

35

40

45y pe

riod

35

40

45y pe

riod

20

25

30

e pe

r 16

 da

early

med20

25

30

e pe

r 16

 da

early

med

5

10

15

20

lbs N/acre med

late*

5

10

15

20

lbs N/acre med

late*

0

5

6‐Oct

‐Nov

‐Nov

‐Dec

‐Dec

4‐Jan

0‐Jan

‐Feb

‐Mar

‐Mar

4‐Apr

‐Apr

0

5

6‐Oct

‐Nov

‐Nov

‐Dec

‐Dec

4‐Jan

0‐Jan

‐Feb

‐Mar

‐Mar

4‐Apr

‐Apr

26 11‐

27‐

13‐

29‐

14 30 15‐

3‐ 19‐ 4 2026 11‐

27‐

13‐

29‐

14 30 15‐

3‐ 19‐ 4 20

Peak rate of nitrogen uptake occurs g pduring jointing, between tilleringand anthesis (flowering)and anthesis (flowering)

Winter cereal uptake types

EarlyTime of maximum

rate of N uptake

Di k i Wh t

Cayuse Oat

Dirkwin Wheat

Swan Oat

Winter cereal uptake types

MediumTime of maximum

rate of N uptake

T2700 Triticale

Longhorn Wheat

Ensiler Oat

Winter cereal uptake types

LateTi f Time of maximum rate of N rate of N uptake

Annual Ryegrass

Winter Cereal Forage Nitrogen Uptake by 

50

e e ea o age oge Up a e byPeriod of Peak Nitrogen Uptake

35

40

45y pe

riod

20

25

30

e pe

r 16

 day

early

med

5

10

15

20

lbs N/acre med

late*

0

5

‐Oct

‐Nov

‐Nov

‐Dec

‐Dec

‐Jan

‐Jan

‐Feb

Mar

Mar

‐Apr

‐Apr

26 11‐

27‐

13‐

29‐

14 30 15‐

3‐ 19‐ 4 ‐ 20‐

The pattern of nitrogen uptake depends on p g p phow much the crop grows during the winter

N uptake table Oct 26 planting, Denair

Lbs/acre Nitrogen Uptake per 16 day Periodeach period cumulative

early med late* early med late*

26-Oct 0 0 0 0 0 011‐Nov 9 5 2 9 5 227 Nov 9 6 2 18 11 4

p

27‐Nov 9 6 2 18 11 413‐Dec 9 6 2 26 17 629‐Dec 8 6 2 34 23 814‐Jan 9 7 3 43 30 1130-Jan 10 9 4 53 38 1515‐Feb 12 12 6 65 50 213‐Mar 13 14 10 78 64 3119 Mar 15 18 17 93 82 4819-Mar 15 18 17 93 82 484-Apr 14 19 27 107 101 7520-Apr 12 19 45 119 120 120

*early, med & late refer to how soon thetime of maximum daily update occurs

Download the model from manure.ucdavis.edu

(but not just yet)

When does the peak N uptake occur?When does the peak N uptake occur?

Nit Nitrogen Uptake Uptake

bybyAlfalfa

Nitrogen Uptake by Alfalfa

AlfalfaAlfalfa– Fixes N2 (gas) from

atmosphereatmosphere– Symbiotic bacteria

• If N is present in soil, alfalfa will use it first, up to 75 to 90% of crop needs.

• Maintain N fixing capacity

• N runs out, full N fixation resumes

• No yield loss from lack of N

Remediation using Alfalfa

• Alfalfa can root more deeply and Alfalfa can root more deeply and capture deeper N

• But misses more than fibrous cereal troots

• Consider interplanting grass with alfalfa in remediation situations

Manure on Alfalfa

Manure on Alfalfa Pros:Pros:

– Bring less N onto the dairy in purchased hay-helps whole-farm balancehay helps whole farm balance

– No yield penalty for missed timing

– Takes up a LOT of N

N removal per ton of harvested alfalfa(CP @ 100% DM, Tons/acre @ 90% DM)

8 tons @ avg. 22% CP = % Crude Protein

N removal lbs/ac

26 75

8 tons @ avg. 22% CP

507 lbs N/acre removal

25 7224 6923 66

507 minus ~ 20% = (accounting for some N fixation)

22 6321 6020 58

507 – 101 = 406 lbs/A

30 T corn @ 8 5% ~ 250 lbs/A19 5518 52

30 T corn @ 8.5% 250 lbs/A

13 T forage @ 12% ~ 150 lbs/A

Manure on Alfalfa • Cons:Cons:

– WeedsSalt injury to crop– Salt injury to crop

– Contamination of hay with solidsManure in runoff– Manure in runoff

– Solids smother crownsE i t i i h– Excessive potassium in hay

Timing applications• SolidSolid

– Apply well before planting to minimize risk of salt injuryof salt injury

– Incorporate immediately and Pre irrigate Incorporate immediately and Pre irrigate immediately after incorporation to conserve ammonia-form N

Timing applications• LiquidLiquid

– Let the irrigation run with fresh water for awhile prior to adding lagoon water to awhile prior to adding lagoon water to facilitate better distribution of solids

– Time applications to avoid leaching losses

Timing applicationsTiming applications– Little uptake during establishment

Timing applicationsTiming applications– Less in spring and fall when growth is

slower

Timing applicationsM t f th t k h tti – Most of the uptake each cutting occurs after 10 days to 2 weeksInitial regrowth: 1/3 1/2 from stored N in – Initial regrowth: 1/3-1/2 from stored N in rootsIf 2 irrigations per cutting apply in 2nd– If 2 irrigations per cutting, apply in 2ndirrigation under leaching conditions

Plowdown credit when stand is taken outPlowdown credit when stand is taken out

Depends on how strong the stand was

Winter forage planted Oct 25

Designing an N budget

Winter forage planted Oct 25Corn planted April 29

Early tassel

8 leaves

G l h it il bl i il Goal: have nitrogen available in soil when the crop needs it

How much to apply

Amount of N to applyAmount of N to applyAmount of N to applyAmount of N to apply

Amount removed at harvest

Amount needed to grow roots leaves & grainroots, leaves & grain

Apply extra to accommodate losses

How much leaching is occurring?g g

Questions?Questions?manure ucdavis edumanure.ucdavis.edu