Nitrogen and Potassium Utilization in Almond Orchards. F.J.A. Niederholzer UC ANR CE Farm Advisor, Colusa/Sutter/Yuba Counties February 7 th, 2017

Transcription

1 Nitrogen and Potassium Utilization in Almond Orchards F.J.A. Niederholzer UC ANR CE Farm Advisor, Colusa/Sutter/Yuba Counties February 7 th, 2017

2 This talk will cover the following topics. Annual N Treatme nt (N/acre) 2008 Kernel yield (lb/acre) 2009 Kernel yield (lb/acre) 2010 Kernel yield (lb/acre) 2011 Kernel yield (lb/acre) 125 lb 3,506 a 2,715 a 2,849 a 3,811 a 200 lb 3,534 a 2,943 ab 3,413 b 4,274 b 275 lb 3,732 a 3,183 b 3,734 bc 4,643 c 350 lb 3,733 a 3,489 b 4,030 c 4,735 c Why N & K matters in almond production Effective, efficient and safe N & K management N & K in the soil and trees

3 Within a year of changes in N fertilizer treatments, yield differences can appear. Annual N Treatment (N/acre) 2008 Kernel yield (lb/acre) 2009 Kernel yield (lb/acre) 2010 Kernel yield (lb/acre) 2011 Kernel yield (lb/acre) 125 lb 3,506 a 2,715 a 2,849 a 3,811 a 200 lb 3,534 a 2,943 ab 3,413 b 4,274 b 275 lb 3,732 a 3,183 b 3,734 bc 4,643 c 350 lb 3,733 a 3,489 b 4,030 c 4,735 c ROI P. Brown, UC Davis

4 Nutrient Nutrient removed in 1000 lb kernel crop Nutrient/acre removed in average crop Potassium 80.0 lbs lbs Nitrogen 68.0 lbs lbs Phosphorus 8.96 lbs lbs Calcium 6.68 lbs lbs Magnesium 4.64 lbs lbs Sulfur 2.62 lbs 6.39 lbs Boron 0.31 lbs 0.76 lbs Iron 0.19 lbs 0.46 lbs Zinc 1.12 oz 2.72 oz Manganese 0.68 oz 1.66 oz Copper 0.34 oz 0.83 oz P. Brown, UC Davis

5 Nitrate concentrations in many CA wells exceed drinking water standards Red dots represent wells that exceed the drinking water standards.

6 Excessive orchard N risks increasing hull rot and yield loss.

7 Potassium fertilization provides a return on investment, especially after heavy crop year. Treatment (K 2 O/acre/ year) 1998 Kernel yield (lb/acre) 1999 Kernel yield (lb/acre) 2000 Kernel yield (lb/acre) 0 lb 780 a 3930 a 2410 a ROI (income$: fertk$) 240 lb 890 a 3840 a 2860 b 600 lb 830 a 4380 a 2860 b 960 lb 1070 a 4020 a 2770 b Reidel, Weinbaum, Brown and Duncan, UC Davis

8 The NITROGEN CYCLE in soils. Singer and Munns, Soils: An Introduction. 2002, page 173

9 Singer and Munns, Soils: An Introduction. 2002, page 229 Potassium Cycle in soil.

10 Potassium and nitrogen reach roots by two processes: mass flow and diffusion. Generally, N is more soil mobile than K. Nutrient Root interception Mass Flow Diffusion Nitrogen Potassium At the root surface, plants expend energy to absorb the nutrients.

11 In the tree, potassium is a chemical activator/regulator, while nitrogen is a essential ingredient of proteins, etc. Function Feedback mechanism limiting uptake? Nitrogen Essential ingredient in molecules in plant Yes Potassium Helps regulate essential processes and transport within the plant No (luxury consumption)

12 The timing of greatest need for available N is March to June, when the crop is growing. P. Brown, UC Davis

13 The amount of N (and K) needed during March to June is driven by cropload Same orchard orchard N use is 200 lbs N/acre LESS than 2011 due to very light 12 crop. P. Brown, UC Davis

14 Almond nut K & N accumulation patterns differ during a growing season. Lb N per 1000 lb crop Lb K per 1000 lb crop Days after full bloom Days after full bloom Nitrogen storage in woody tissue = 40 lbs N/acre Potassium storage in woody tissue = 25 lbs K/acre P. Brown, UC Davis

15 Traditional orchard fertility test (leaf analysis) are a good indication of deficient, but not excessive nutrients. P. Brown, UC Davis

16 The 4 R s of Fertilizer management are the guiding strategy for all nutrients & especially Nitrogen and Potassium. Right Rate Right Time Right Location Right Material

17 The 4 R s of Fertilizer management are the guiding strategy for all nutrients & especially Nitrogen and Potassium. Right Rate Right Time Right Location Right Material

18 1. Use yield history to estimate annual budget. Ante up: apply 20% of annual budget by mid-march. Application Timing % of total budget Lb. N per application if it s a normal crop Bloom-leaf out (Feb-Mar) 20% 47 April 30% May/June 30% Hull split to postharvest 20%

19 Experience & spring leaf test results helps decide N & K inputs after first 20% of annual N budget is applied.

20 In season, use spring leaf levels (N) to revise fertilizer program on the go. UC ESP (Early season Protocol) 43 days (± 6 d.) after full bloom Take all leaves of 2-3 non-bearing spurs around the tree Sample trees at least 90 feet apart Request full nutrient analysis from lab Plug results into UC model in Excel. Find the model at: emand Patrick_Brown/ or

21 2. Use experience, bloom weather & spring leaf N levels to decide on April-June rates (30% & 30% of total if all appears normal ). Application Timing % of total budget Lb. N per application if it s a normal crop Bloom-leaf out (Feb-Mar) 20% 47 April 30% 71 May/June 30% 71 Hull split to postharvest

22 3. Use actual cropload and summer leaf N analysis to determine how much, if any, postharvest N to apply. Application Timing % of total budget Lb. N per application if it s a normal crop Bloom-leaf out (Feb-Mar) 20% 47 April 30% 71 May/June 30% 71 Hull split to postharvest 20% 47?

23 An example of differences in yields and N use in the same orchard. Nickels pruning trial Variety Yield/acre N use/acre* Nonpareil 2, Monterey 2, Aldrich 2, Carmel 2, *Assumes 68 lbs N/1000 lbs crop for all varieties

24 Irrigation systems can be designed to treat varieties separately.

25 Potassium timing and rates are similar to nitrogen for the same cropload. Application Timing % of total budget Lb. K 2 O per application if it s a normal crop Bloom-leaf out (Feb-Mar) 20% 46 April 30% 70 June 30% 70 Hull split to postharvest 20% 46

26 Summer leaf levels are a report card for preharvest fertility & key planning input(s) for postharvest fertility program. Critical July leaf nutrient concentration (%) Old target New target Nitrogen Potassium >

27 The 4 R s of Fertilizer management are the guiding strategy for all nutrients & especially Nitrogen and Potassium. Right Rate Right Time Right Location Right Material

28 Right Place: Irrigation Rapidly Moves N into Soil Surface applied N Followed by Irrigation (90 minutes) Broadbent, 1958, graph from

29 In season, use K deficiency leaf symptoms (or early leaf sampling from private lab) to revise fertilizer program on the go.

30 Soil CEC (soil K storage potential) influences K input plans & practices. Practice Dormant Soil Applications Banding gypsum to move potassium In-Season Applications Fertigation of K High CEC Soil (>15 meq/100 g of soil) Yes can be slugged on Yes, if heavy clay Yes, if needed Yes Low CEC soil (<15 meq/100g of soil) Yes but only partial budget NO Yes % of the budget Yes be cautious of large applications

31 No benefit from applying more than 240 lbs K2O/acre/year has been measured in short (< 5 years) UC trials.

32 Right timing, location, & rate are vital to effective, efficient & safe N & K fertilization. Material is less critical. Nitrogen Potassium Annual Rate* Timing Location 68 lbs N Mar-early June; Sept Tree row, upper 0-2 root zone 80 lbs K (96 lbs K 2 O) Mar-June; Sept. Tree row, upper 0-2 root zone Material Grower choice Grower choice *per 1000 lbs kernel crop (includes hull, shell and kernel). Adjust annual rate for the current year based on cropload and tissue tests

33 Thank you