1. Reducing Orchard Fertilizer Costs Lenny Wells UGA Horticulture

2. Fertilizer Costs Ammonium Nitrate (33% N)  2007/08 = $457/ton »($103.86/Acre based on 150 lbs N/A) Phosphorous (44% P 2 0 5 ) »$12.80/Acre (40 lbs/A) Potash (51%K)  2007/08 = 475/ton (51%K) »($28.50/acre based on 60 lbs K/acre) Zinc$17.50/Acre (50 lbs/Acre) Total:$162.66/Acre

3. Are we using too much N? Yield and leaf N of Mature ‘Stuart’ trees in good condition did not respond to N at rates of 0-120 lbs/A until 6 years later (Worley 1974). Pecan Orchards cycle nutrients

4. Why is Organic Matter Important? Higher inputs required with lower organic matter Increased Water-Holding Capacity Nitrate provided to plants via mineralization as soil organisms decompose organic matter Neg. charged humus holds K, Ca, Mg, preventing loss Provides natural chelates that keep Zn and Cu in forms plants can use Reduced compaction, better water-holding capacity, reduced erosion Slows down (Buffers) changes in pH For every 1% increase in organic matter, 10 lbs N released Crop yield increased 12% for every 1% increase in organic matter

5. N Credit for Legumes General N Recommendation for Pecans  10 Lbs N/ 100 lbs expected crop Crimson Clover  Year 1 = Replaces 30 lbs N/Acre  On Year = 150 lbs N-30 lbs N = 120 lbs N/Acre  Off YEAR= 75 lbs – 30 lbs = 45 lbs N/Acre  After 3 Years = Replaces 75-150 lbs N/Acre  On Year = 150 lbs N – 100 lbs N = 50 lbs N/Acre  Off Year = No additional N required

6. Effect of Clover on Organic Matter and N Sample SiteNitrate-NOrganic Matter 4” Sod3.781.34 8” Sod4.181.66 4” Sod+Clover13.952.32 8” Sod + Clover10.752.90 Orangeburg Loamy Sand

7. Poultry Litter Costs Total Synthetic Cost N,P,K,Zn = 162.66 1 ton litter = $35-$50  1 appl.: $50/Acre for 39 lbs N, 48 lbs P, +K, +Zn  2 appl.: $100/Acre for 78 lbs N, 96 lbs P, +K, +Zn Not much difference if N is only benefit (@ $50/ton)

8. Nitrogen Costs (Assuming 150 lbs N for ON year) Broadcast Ammonium Nitrate Clover + Ammon. Nitrate Clover + Litter On Year$103.86/Acre$34.27/Acre$50-$75/Acre Off Year$51.83/Acre$0/Acre If only N needed If N,P,K,Zn needed

9. Band Applications Apply fertilizer over the drip emitter line More efficient/reduced fertilizer cost Determine area of application!

10. Which makes more sense? (100 acre orchard on 60 X60) Broadcast Ammonium Nitrate Clover + Ammon. Nitrate Clover + Litter Clover+ Band Appl. On Year (150 lbs N/Acre) $103.86/Acre$34.27/Acre$50- $75/Acre $9.20/Acre Off Year (75 lbs N/Acre) $51.83/Acre$0/Acre

11. Boron Recommendations Can increase fruit retention and kernel percentage 3 pre-pollination applications of B beginning before catkins are mature No benefit to making more than 3 applications

12. Nickel Improves Mouse-ear Symptoms Effects of Nickel on N metabolism in pecan:  Can influence the efficiency of early spring N conversion and transport within the pecan tree (Bai et al. 2007). 2 applications: Early to mid April and again 2-4 weeks later

13. Weed Control and Clover

15. Sandea (Halosulfuron-methyl)  Excellent on wild turnips (pre and post-emergence)  Good activity on wild geranium  Good control of rye-grass  Potential Problems:  Cost = $15/acre @ 0.5 oz/acre  Delayed clover development; possible effect on seed viability Basagran  Cost = $16/acre @ 2 pints/acre  Problems: For use only on Non-Bearing Pecans Wild turnip must be treated up to a weed height of 3” Best results on geranium will be achieved when weeds are small Heavier the Infestation, earlier the treatment

16. Yet To Be Determined: 2,4-DB-amine  used for the control of many annual and perennial broad-leaved weeds in alfalfa, peanuts, soybeans  Labeled for clover Timing and rates

17. Uses 5% Glyphosate solution (1.25 gal./25 gal water) + 4% 2,4-D amine Controls difficult weeds like: hophornbeam copperleaf, grasses, and arrowleaf sida Cost per acre varies with weed density