Strip Till Systems for Burley Tobacco in Tennessee

Transcription

1 Strip Till Systems for Burley Tobacco in Tennessee Paul Denton University of Tennessee

2 Objective Evaluate alternative strip till systems for burley tobacco production in Tennessee Compare these systems to no-till and fully tilled systems Conduct evaluations in the two major production regions

3 Tillage systems No till Narrow strip till Wide strip till Rototill strip till Wide strip till + rototill strip Full tillage One pass system with no till transplanter, narrow shank in front of planter shoe, in undisturbed soil One pass with narrow in row shank (6 in winged point) approximately 6 in deep, followed by no till transplanter One (HR) or two (GR) passes with in row subsoiler shank, with angled fluted coulters and rolling basket behind shank, approximately 12 inches deep, followed by transplanter One pass with narrow in row rototill unit, followed by transplanter One pass with in row subsoiler followed by one pass with narrow rototiller, followed by transplanter One pass with chisel plow, one or two passes with full width rototiller, followed by transplanter

4 Fertilizer Treatments 1. All fertilizer surface broadcast 2. Two-thirds of fertilizer surface broadcast, one-third banded beside row 210 lbs/ac N, as ammonium nitrate P and K by soil test

5 No-till No seedbed preparation prior to transplanting Transplanter contains coulter, narrow shank, weight

6 Strip-till Tobacco transplanted into a tilled strip ~30-45 cm wide Subsoiler shank with fluted coulters and rolling basket Narrow rototiller Narrow shank with closing disks

7 Prior cover: Procedures timothy/orchardgrass sod at Greeneville soybean residue at Highland Rim Soil types Dickson silt loam at Highland Rim Decatur loam/clay loam at Greeneville Weed control Greeneville Glyphosate burndown in fall Paraquat two weeks before transplanting Spartan and Command just before transplanting Poast after transplanting Weed control Highland Rim Burndown with Roundup in spring Devrinol and Spartan 2009; Prowl, Devrinol and Spartan 2010 Poast after transplanting

8 Procedures Varieties: Highland Rim: KT 206 LC both years Greeneville: KT 204 LC in 09, TN 90 LC in 10 Standard production practices Transplanted late May early June Dry in 2009 at HR, good growing seasons otherwise Harvest late August mid September

9 2009 Yields Highland Rim Banded Fertilizer No Banded Fertilizer Average* (lbs/ac) No till b* Narrow ST a Rototill ST a Wide ST a Wide ST + Roto ST a Full Tillage a Average** * Means followed by the same letter are not significantly different at P= 10% ** No significant difference in yield between fertilizer treatments

10 2009 Yields - Greeneville Banded Fertilizer No Banded Fertilizer Average* (lbs/ac) No till Narrow ST Rototill ST Wide ST Wide ST + Roto ST Full Tillage Average* * No significant difference in mean yields between treatments at P=10%

11 2010 Yields - Highland Rim No Banded Fertilizer --- (lbs/ac)--- No till 2805 c* Narrow ST 3016 bc Rototill ST 3239 ab Wide ST 3151 ab Wide ST + Roto ST 3250 ab Full Tillage 3354 a * Means followed by the same letter are not significantly different at P= 10%

12 2010 Yields - Greeneville Banded Fertilizer No Banded Fertilizer Average* (lbs/ac) No till b* Narrow ST b Rototill ST b Wide ST b Wide ST + Roto ST b Full Tillage a Average** * Means followed by the same letter are not significantly different at P= 10% ** No significant difference in yield between fertilizer treatments

13 Yield Across Years and Locations Tillage System Yield --- (lbs/ac)--- No till 2709 c* Narrow ST Rototill ST Wide ST 2859 b 2965 ab 2943 ab Wide ST + Roto ST 2971 ab Full Tillage 3064 a * Means followed by the same letter not significantly different at P = 0.10.

14 Soil Residue Cover GREC 6/22/09 Tillage System % Residue Cover No till 41 Narrow ST 29 Rototill ST 14 Wide ST 7 Wide ST + Roto ST 4 Full Tillage 4

15 Conclusions Strip till with a subsoiler shank or rototiller appears to be essentially equal to full tillage use of rototiller after subsoiler same as two passes with subsoiler Narrow strip till with single pass Sometimes gave lower yield than wider strip till Likely impractical due to difficulty of transplanting No-till yields tend to be lower than tilled works better in well-drained, well structured soils

16 Conservation Tillage for Burley? Strip till equal to full tillage, no-till lags in yield No till works better on well structured soils Requires more management than tilled Weed control Good control possible with herbicides alone Still likely to require some hand weeding Proper transplant depth and good root ball - soil contact are critical Soil conditions at tillage and transplanting time Properly adjusted and operated equipment Low residue cover a concern with early burndown and aggressive strip till