Nitrogen Uptake of Corn, Cereal Forage and Alfalfa Marsha Campbell Mathews Farm Advisor University of California CE Stanislaus County David Crohn Waste Management Specialist University of California Riverside
Central Valley Regional Water Quality Control Board Dairy Waste Discharge Requirement 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 nitrogen it needs in the right form in the correct amount at the proper time
Calculating total removal Silage Total Removal 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/acre
Calculating total removal Hay Total Removal Lbs dry matter/a x % N Lbs dry matter/a x % protein/6.25 Tons/A @ 70% x % protein x 2.88
Nitrogen Uptake by Silage Corn
When does corn need nitrogen? Original work by Hanaway, 1962 (How a corn plant develops) Redone with modern hybrids Sheppers, Francis, et al Staygreen hybrids continue to take up & use N R. D. Meyer (UCCE) 4 yrs in Merced County J. Mitchell, Mathews, Crohn (UCCE) 3 yrs Stanislaus County
Nitrogen Uptake of Grain Corn Growth stage % total uptake 6 leaf 5-10% 12 leaf 30-35% 35% 18 leaf 70-75% Tassel/silk 75-80% Blister 80-85% Dough 100% Based on classic work by Hanaway, 1962
Lbs N p per acre e per day y -2-4 Full dent Blister ear Full tassel 12 leaves 8 leaves 4 leaves 5 leaves 8 leaves 12 leaves Early tassel 14 12 10 8 6 4 2 0
Lbs N p per acre e per day y 0-2 -4 Full dent Blister ear 12 Full tassel 12 leaves 8 leaves 4 leaves silking full dent 14 blister ear 10 8 6 4 2
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% 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 Growth Stage in tops uptake Silking -12 Blister 13 66% 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 Uptake 1998-2000 Corn N uptake by GDU Hilmar, CA R. D. Meyer, M. C. Mathews, T. Harter N uptak ke, lbs/a 450 400 350 300 250 200 150 100 50 0 lking sil Grain corn will remobilize N & K from lower leaves & stalk into grain 33.4* RB98 29.8* RB99 31.2* RB00 41.6* B 98 33.3* B 99 35.7* B 00 *T/A @ 70% Moisture % N uptake at silk (estimated) 69% 65% 79% 60% 68% 52% Avg 68% 0 1000 GDU 2000 3000
Corn N uptake Grain: 80% before tassel/silking Silage: 1/3 after tassel/silking Potassium uptake for corn is similar to nitrogen in amount & timing
Nitrogen Uptake by Cereal Forage
Cereal Forage Plantings from early October to December Harvest at different growth stages Many types with vastly different growth habits Different nitrogen contents 10 tons @ 8% protein 10 tons @ 8% protein = 80 lbs N/acre vs 20 tons @ 17% protein = 340 lbs N/acre
Most nitrogen uptake work on cereals focuses on the period from flowering to grain fill 1997 to 2002 1997 to 2002 Clipping studies with multiple locations, varieties, planting dates. Cut about every 10 days
Massive amounts of data N must be sufficient at all times Considerable variability
Massive amounts of data N must have been sufficient at all times Considerable variability David Crohn, UCR
Most parameters many ygrowers have available already: Planting Date Harvest Date Expected N removal Min Max Temperatures to calculate Growing Degree Days Variety parameter for winter growth/n uptake
Winter Cereal Forage Nitrogen Uptake by Period of Peak Nitrogen Uptake 50 45 40 35 30 25 20 15 10 5 0 early med late* lbs N/acre per 16 da y period 26 6 Oct 11 Nov 27 Nov 13 Dec 29 Dec 14 4 Jan 30 0 Jan 15 Feb 3 Mar 19 Mar 4 Apr 20 Apr
Peak rate of nitrogen uptake occurs during jointing, between tillering and anthesis (flowering)
Winter cereal uptake types Early Time of maximum rate of N uptake Cayuse Oat Dirkwin i Wheat Swan Oat
Winter cereal uptake types Medium Time of maximum rate of N uptake T2700 Triticale Longhorn Wheat Ensiler Oat
Winter cereal uptake types Late Time of maximum rate of N uptake Annual Ryegrass
Winter Cereal eea Forage oage Nitrogen Uptake by Period of Peak Nitrogen Uptake 50 45 40 35 30 early 25 med late* 20 15 10 5 0 lbs N/acre per 16 day period 26 Oct 11 Nov 27 Nov 13 Dec 29 Dec 14 Jan 30 Jan 15 Feb 3 Mar 19 Mar 4 Apr 20 Apr
The pattern of nitrogen uptake depends on p g p p how much the crop grows during the winter
N uptake table Oct 26 planting, Denair Lbs/acre Nitrogen Uptake per 16 day Period each period cumulative early med late* early med late* 26-Oct 0 0 0 0 0 0 11 Nov 9 5 2 9 5 2 27 Nov 9 6 2 18 11 4 13 Dec 9 6 2 26 17 6 29 Dec 8 6 2 34 23 8 14 Jan 9 7 3 43 30 11 30-Jan 10 9 4 53 38 15 15 Feb 12 12 6 65 50 21 3 Mar 13 14 10 78 64 31 19-Mar 15 18 17 93 82 48 4-Apr 14 19 27 107 101 75 20-Apr 12 19 45 119 120 120 *early, med & late refer to how soon the time of maximum daily update occurs
Download the model from manure.ucdavis.edu (but not just yet)
When does the peak N uptake occur?
Nitrogen Uptake by Alfalfa
Nitrogen Uptake by Alfalfa Alfalfa Fixes N 2 (gas) from atmosphere 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 capture deeper N But misses more than fibrous cereal roots Consider interplanting grass with alfalfa in remediation situations
Manure on Alfalfa Manure on Alfalfa Pros: Bring less N onto the dairy in purchased hay-helps helps whole-farm balance No yield penalty for missed timing Takes up a LOT of N
8 tons @ avg. 22% CP = 507 lbs N/acre removal 507 minus ~ 20% = (accounting for some N fixation) 507 101 = 406 lbs/a 30 T corn @ 8.5% ~ 250 lbs/a 13 T forage @ 12% ~ 150 lbs/a N removal per ton of harvested alfalfa (CP @ 100% DM, Tons/acre @ 90% DM) % Crude Protein N removal lbs/ac 26 75 25 72 24 69 23 66 22 63 21 60 20 58 19 55 18 52
Manure on Alfalfa Cons: Weeds Salt injury to crop Contamination of hay with solids Manure in runoff Solids smother crowns Excessive potassium in hay
Timing applications Solid Apply well before planting to minimize risk of salt injury Incorporate immediately and Pre irrigate Incorporate immediately and Pre irrigate immediately after incorporation to conserve ammonia-form N
Timing applications Liquid Let the irrigation run with fresh water for awhile prior to adding lagoon water to facilitate better distribution of solids Time applications to avoid leaching losses
Timing applications Little uptake during establishment
Timing applications Less in spring and fall when growth is slower
Timing applications Most of the uptake each cutting occurs after 10 days to 2 weeks Initial regrowth: 1/3-1/21/2 from stored N in roots If 2 irrigations per cutting apply in 2 nd If 2 irrigations per cutting, apply in 2 nd irrigation under leaching conditions
Plowdown credit when stand is taken out Depends on how strong the stand was
Designing an N budget Winter forage planted Oct 25 Corn 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 apply Amount removed at harvest Amount needed to grow roots, leaves & grain Apply extra to accommodate losses How much leaching is occurring?
manure.ucdavis.eduucdavis edu Questions?