Oakes Irrigation Research
Site
Carrington Research Extension Center * North Dakota State University
P.O. Box 531, Oakes, ND 58474-0531, Voice: (701) 742-2189, FAX: (701)
742-2700, email: rgreenla@ndsuext.nodak.edu
CARROT TILLAGE AND POPULATION STUDY
Richard Greenland
Table 48. List of treatments.
Table 49. Quantity and yield of carrots in a bedded carrot study. Comparison of hybrid, seeding rate, rows per bed, and tillage treatments - August harvest.
Table 50. Quality characteristics of carrots in a bedded carrot study. Comparison of hybrid, seeding rate, rows per bed, and tillage treatments - August harvest.
Table 51. Quantity and yield of carrots in a bedded carrot. Comparison of hybrid, seeding rate, rows per bed, and tillage treatments - September harvest.
Table 52. Quality characteristics of carrots in a bedded carrot. Comparison of hybrid, seeding rate, rows per bed, and tillage treatments - September harvest.
Table 53. Quantities of carrots in a flat planted carrot study. Comparison of hybrid, seeding rate, and tillage treatments - August harvest.
Table 54. Yield of carrots in a flat planted carrot study. Comparison of hybrid, seeding rate, and tillage treatments - August harvest.
Table 55. Quality of carrots in a flat planted carrot study. Comparison of hybrid, seeding rate, and tillage treatments - August harvest.
Table 56. Quantities of carrots in a flat planted carrot study. Comparison of hybrid, seeding rate, and tillage treatments - September harvest.
Table 57. Yield of carrots in a flat planted carrot study. Comparison of hybrid, seeding rate, and tillage treatments - September harvest.
Table 58. Quality of carrots in a flat planted carrot study. Comparison of hybrid, seeding rate, and tillage treatments - September harvest.
Table 59. Quantities of carrots in a tillage by seeding rate study. Comparison of hybrid, seeding rate, and tillage treatments - August harvest.
Table 60. Yield of carrots in a tillage by seeding rate study. Comparison of hybrid, seeding rate, and tillage treatments - August harvest.
Table 61. Quality of carrots in a tillage by seeding rate study. Comparison of hybrid, seeding rate, and tillage treatments - August harvest.
Table 62. Quantities of carrots in a tillage by seeding rate study. Comparison of hybrid, seeding rate, and tillage treatments - September harvest.
Table 63. Yield of carrots in a tillage by seeding rate study. Comparison of hybrid, seeding rate, and tillage treatments - September harvest.
Table 64. Quality of carrots in a tillage by seeding rate study. Comparison of hybrid, seeding rate, and tillage treatments - September harvest.
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INTRODUCTION
Carrots are usually planted on raised beds. The raised beds have loose soil which allow the carrots to grow long and straight. Carrots planted on flat ground usually are more crooked and shorter because of compacted soil and plow pans. But making raised beds reduces the surface area for planting carrots, so carrots are crowded together on top of the beds. Also, during the growing season the sides of the beds erode away leaving some carrot root tops exposed which causes green or red colored root tops, which in turn reduce carrot quality. Planting carrots on flat ground would solve these last two problems, but the soil needs to be loosened. We tried two methods to loosen the soil. We used a coulter chisel to rip the soil 14 inches deep or a soil spader to till the soil 12 inches deep. We compared these two treatments to carrots planted on beds. We also included a population study with the tillage study, and included two carrot hybrids.
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MATERIALS AND METHODS
| Soil: | Maddock sandy loam; pH=8.0; 2.6% organic matter; soil-P and soil-K were very high; soil-S was low. |
| Previous crop: | 1998 - cabbage and potato; 1997 - onion and sweet corn; 1996 - pumpkin, winter squash, potato and onion. |
| Seedbed Preparation: | Disked entire study on 4 November 1998. See Table 48 for tillage treatments. Depth the soil was worked: Soil spader 12", coulter chisel 14", disk 5 to 6", field cultivator 3 to 5". Beds were lightly rototilled once and flat planted areas were field cultivated shallow twice to incorporate herbicides just before planting. |
| Planting: | Direct seeded on May 25 and May 26 with a Stanhay vegetable planter. Planting pattern for all carrots was paired rows (3 inches between rows in the pair). See Table 48 for number of paired rows, spacing and seeding rates. |
| Plots: | Plots were 17 ft long. Beds were 36 inches wide on 54 inch centers. Plots planted flat were 72 inches on center. See Table 48 for population and row spacing. There were 4 reps. |
| Fertilizer: | On April 7, broadcast 15 lbs N/acre and 75 lbs P2O5/acre as 10-50-0, 18 lbs N/acre and 20 lbs S/acre as 21-0-0-24, and 99 lbs K20/acre as 0-0-60. Applied 50 lbs N/acre as 28-0-0 on June 29. |
| Irrigation: | Sprinkler irrigation as needed. |
| Pest control: | Weeds were controlled using Treflan (1.5 pt/acre on May 19), Linex (1 lb/acre on May 27 and 1.7 lb/acre on June 29), Poast + Dash (1.5 pt + 1 qt/acre on June 11), Poast + Fusilade + Dash (1.5 pt + 12 oz + 1 pt/acre on July 13), and by hand weeding. We sprayed Sevin (1 qt/acre on July 13 and July 27) and Asana (8 oz/acre on June 29, July 6, July 21, Aug 3, and Aug 24) to control leafhopper. |
| Harvest: | Plots were harvested twice from August 19 through September 23. Harvest area was a three foot section of each plot. The four center rows of the flat planted plots and one bed, on the plots that were bedded, were harvested. |
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Comparisons of hybrids, seeding rates, number of rows per bed, and tillage (disk vs. coulter chisel) are given in Tables 49 to 52. These results include only those carrots planted on beds. Bolero had higher carrot yields and a shorter, fatter root compared to Prime Cut. The difference was due to higher germination and better plant stands with Bolero. Increasing the seeding rate from 1 to 1.5 million decreased carrot yield, percentage of US #1 carrots, and root size. The reduction was due to smaller carrots being produced with the higher plant population. Putting three rows on each bed spread the carrots out more (the in-row spacing was greater), but this did not increase yield or affect carrot quality. Tillage did not affect carrot yield or quality when carrots were grown on beds.
Comparisons of hybrids, seeding rates, and tillage for flat planted carrots are given in Tables 53 to 58. Bolero had higher plant numbers and higher yields than Prime Cut. It also had a shorter, fatter, lighter weight root than Prime Cut. Increasing the seeding rate decreased large carrot number and yield, and increased small carrot number and yield. Highest total yields were with seeding rates of 1 to 1.5 million for the August harvest, and 0.5 to 1.5 million for the September harvest. Production of cut and peel or cello carrots would benefit from a higher seeding rate since they are harvested earlier. Increasing the seeding rate would not benefit carrots grown for processing since they are harvested late. Root diameter and weight decreased with increasing seed rate, but root length was not affected by seeding rate. The effect of a higher seeding rate was more pronounced with Bolero than with Prime Cut. Being long and thin, the Prime Cut is better able to handle higher populations. The fat Bolero carrot is crowded more easily. The percent US #1 carrots, carrot root length, and US #1 yields were greater, and the percent of carrots with multiple roots decreased when a soil spader was used for tillage vs. a coulter chisel. This was probably due to a looser soil with the soil spader.
Comparisons of hybrids, seeding rates, tillage, and beds vs. flat planting are given in Tables 59 to 64. The effects of hybrid and seeding rate were similar to the other parts of this study. Number and yield of US #1 carrots were greater when carrots were planted flat vs. being planted on beds. Quality of carrots was better with flat planting as shown by higher percent US #1 carrots and lower percent carrots with multiple roots. Roots of flat planted carrots were longer (August harvest) or equal (September harvest) to carrots grown on beds.
CONCLUSIONS
Bolero germinated, grew better, had higher yields, and was shorter and fatter than Prime Cut. When carrots were grown on beds, increasing the seeding rate decreased yields, but when grown flat, increasing the seeding rate (up to 1.5 million) increased yields of carrots harvested early (for cello or cut and peel markets) and didn't improve yields of carrots harvested late (for processing markets). Planting carrots on flat ground produced higher yields and better quality carrots than planting on beds provided that a coulter chisel or soil spader was used to prepare the seedbed. The soil spader was slightly better than the coulter chisel.
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Table 48. List of treatments for the carrot tillage/population study.
| Tillage | Bed vs. flat | No. of paired rows per bed | Row spacing | Plant populations |
| inches | millions | |||
| Disk | bed | 2 or 3 | 16 or 8 | 1 or 1.5 |
| Coulter chisel | bed | 2 or 3 | 16 or 8 | 1 or 1.5 |
| Coulter chisel | flat | - | 16 | 0.5, 1, 1.5, or 2.0 |
| Soil spader | flat | - | 16 | 0.5, 1, 1.5, or 2.0 |
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Table 49. Quantity and yield of carrots in a bedded carrot study at the Oakes Irrigation Research Site. Comparison of hybrid, seeding rate, rows per bed, and tillage treatments - August harvest.
| Treatment | Number of US #1 carrots | US #1 carrot yield | Total yield | ||||
| > 1" | ¾ to 1" | total | > 1" | ¾ to 1" | total | ||
| 1000s of roots/acre | tons/acre | ||||||
| Hybrid | |||||||
| Bolero | 140 | 230 | 628 | 11.6 | 8.0 | 19.7 | 30.0 |
| Prime Cut | 63 | 161 | 480 | 5.8 | 7.0 | 12.8 | 22.0 |
| Probability | 0.005 | 0.03 | 0.011 | 0.01 | 0.24 | 0.008 | 0.004 |
| Seeding rate | |||||||
| 1 million | 107 | 171 | 476 | 9.7 | 6.8 | 16.5 | 25.9 |
| 1.5 million | 95 | 220 | 633 | 7.7 | 8.3 | 16.0 | 26.1 |
| Probability | 0.053 | 0.002 | 0.0001 | 0.0001 | 0.004 | 0.51 | 0.76 |
| Rows per bed | |||||||
| Two | 95 | 180 | 546 | 8.5 | 7.0 | 15.5 | 25.9 |
| Three | 107 | 211 | 563 | 8.9 | 8.0 | 17.0 | 26.1 |
| Probability | 0.04 | 0.04 | 0.54 | 0.35 | 0.06 | 0.06 | 0.85 |
| Tillage | |||||||
| Disked | 102 | 197 | 532 | 8.9 | 7.6 | 16.6 | 25.8 |
| Coulter chisel | 101 | 194 | 577 | 8.5 | 7.4 | 15.9 | 26.2 |
| Probability | 0.82 | 0.84 | 0.31 | 0.09 | 0.75 | 0.26 | 0.70 |
| C. V. (%) | 22 | 29 | 19 | 21 | 26 | 17 | 10 |
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Table 50. Quality characteristics of carrots in a bedded carrot study at the Oakes Irrigation Research Site. Comparison of hybrid, seeding rate, rows per bed, and tillage treatments - August harvest.
| Treatment | US #1 > 1" | Total US #1 |
Multiple root | Straight score† | Root size | Root length | Root diameter |
| % | 1 to 10 | oz/root | inches | ||||
| Hybrid | |||||||
| Bolero | 39 | 65 | 16 | 5.8 | 1.7 | 8.7 | 1.08 |
| Prime Cut | 26 | 59 | 21 | 5.8 | 1.9 | 9.2 | 1.00 |
| Probability | 0.053 | 0.10 | 0.37 | 0.92 | 0.21 | 0.02 | 0.02 |
| Seeding rate | |||||||
| 1 million | 36 | 63 | 20 | 5.8 | 2.0 | 8.9 | 1.05 |
| 1.5 million | 28 | 61 | 17 | 5.9 | 1.7 | 9.1 | 1.04 |
| Probability | 0.0001 | 0.23 | 0.10 | 0.47 | 0.0001 | 0.20 | 0.67 |
| Rows per bed | |||||||
| Two | 32 | 60 | 19 | 5.9 | 1.9 | 9.0 | 1.05 |
| Three | 33 | 64 | 18 | 5.8 | 1.7 | 8.9 | 1.04 |
| Probability | 0.45 | 0.03 | 0.33 | 0.70 | 0.053 | 0.81 | 0.68 |
| Tillage | |||||||
| Disked | 33 | 64 | 20 | 5.9 | 1.8 | 8.9 | 1.04 |
| Coulter chisel | 31 | 60 | 17 | 5.7 | 1.8 | 9.1 | 1.04 |
| Probability | 0.27 | 0.03 | 0.22 | 0.10 | 0.28 | 0.32 | 0.74 |
| C. V. (%) | 21 |
13 | 38 | 8 | 15 | 8 | 9 |
†Straight score indicates how straight the carrots were. 1 is very crooked, 10 is perfectly straight.
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Table 51. Quantity and yield of carrots in a bedded carrot study at the Oakes Irrigation Research Site. Comparison of hybrid, seeding rate, rows per bed, and tillage treatments - September harvest.
| Treatment | Number of US #1 carrots | US #1 carrot yield | Total yield | ||||
| > 1" | ¾ to 1" | total | > 1" | ¾ to 1" | total | ||
| 1000s of roots/acre | tons/acre | ||||||
| Hybrid | |||||||
| Bolero | 231 | 158 | 527 | 20.6 | 5.2 | 25.7 | 35.1 |
| Prime Cut | 139 | 131 | 396 | 14.6 | 5.2 | 19.8 | 29.2 |
| Probability | 0.003 | 0.02 | 0.004 | 0.04 | 0.90 | 0.05 | 0.04 |
| Seeding rate | |||||||
| 1 million | 198 | 122 | 435 | 19.9 | 4.5 | 24.4 | 33.6 |
| 1.5 million | 172 | 167 | 488 | 15.3 | 5.8 | 21.1 | 30.6 |
| Probability | 0.02 | 0.002 | 0.03 | 0.0001 | 0.013 | 0.007 | 0.001 |
| Rows per bed | |||||||
| Two | 176 | 144 | 458 | 17.1 | 5.2 | 22.3 | 32.2 |
| Three | 194 | 145 | 465 | 18.1 | 5.1 | 23.2 | 32.0 |
| Probability | 0.10 | 0.94 | 0.77 | 0.33 | 0.90 | 0.45 | 0.86 |
| Tillage | |||||||
| Disked | 180 | 143 | 446 | 17.3 | 5.1 | 22.4 | 31.6 |
| Coulter chisel | 190 | 146 | 478 | 17.9 | 5.3 | 23.1 | 32.7 |
| Probability | 0.42 | 0.88 | 0.37 | 0.65 | 0.73 | 0.60 | 0.44 |
| C. V. (%) | 22 | 37 | 20 | 21 | 36 | 20 | 13 |
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Table 52. Quality characteristics of carrots in a bedded carrot study at the Oakes Irrigation Research Site. Comparison of hybrid, seeding rate, rows per bed, and tillage treatments - September harvest.
| Treatment | US #1 > 1" | Total US #1 |
Multiple root | Straight score† | Root size | Root length | Root diameter |
| % | 1 to 10 | oz/root | inches | ||||
| Hybrid | |||||||
| Bolero | 58 | 73 | 15 | 5.1 | 2.2 | 8.4 | 1.16 |
| Prime Cut | 50 | 68 | 19 | 5.1 | 2.5 | 9.4 | 1.09 |
| Probability | 0.03 | 0.23 | 0.47 | 0.97 | 0.03 | 0.008 | 0.001 |
| Seeding rate | |||||||
| 1 million | 58 | 72 | 17 | 5.1 | 2.6 | 9.0 | 1.13 |
| 1.5 million | 50 | 69 | 17 | 5.0 | 2.1 | 8.9 | 1.12 |
| Probability | 0.0001 | 0.20 | 0.85 | 0.50 | 0.0001 | 0.49 | 0.75 |
| Rows per bed | |||||||
| Two | 52 | 69 | 17 | 5.1 | 2.3 | 9.0 | 1.12 |
| Three | 56 | 72 | 17 | 5.1 | 2.3 | 8.9 | 1.13 |
| Probability | 0.08 | 0.11 | 0.81 | 0.81 | 0.43 | 0.75 | 0.86 |
| Tillage | |||||||
| Disked | 54 | 70 | 17 | 5.1 | 2.3 | 9.0 | 1.13 |
| Coulter chisel | 54 | 71 | 17 | 5.1 | 2.3 | 8.9 | 1.12 |
| Probability | 0.80 | 0.97 | 0.74 | 0.59 | 0.92 | 0.55 | 0.82 |
| C. V. (%) | 14 |
13 | 39 | 11 | 15 | 9 | 9 |
†Straight score indicates how straight the carrots were. 1 is very crooked, 10 is perfectly straight.
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Table 53. Quantities of carrots in a flat planted carrot study at the Oakes Irrigation Research Site. Comparison of hybrid, seeding rate, and tillage treatments - August harvest.
| Treatment | Number of US #1 carrots (sorted by diameter) | Total roots | ||||
| > 1½" | 1 to 1½ " | > 1" | ¾ to 1" | total | ||
| 1000s of roots/acre | ||||||
| Hybrid | ||||||
| Bolero | 10 | 152 | 162 | 200 | 361 | 587 |
| Prime Cut | 3 | 79 | 82 | 154 | 236 | 459 |
| Probability | 0.12 | 0.005 | 0.005 | 0.012 | 0.005 | 0.01 |
| Seeding rate | ||||||
| 0.5 million | 18 a | 86 b | 104 b | 60 b | 165 b | 234 c |
| 1.0 million | 4 b | 155 a | 159 a | 193 a | 352 a | 536 b |
| 1.5 million | 3 b | 132 a | 135 a | 227 a | 362 a | 629 a |
| 2.0 million | 0 b | 88 b | 88 b | 228 a | 316 a | 695 a |
| Probability | 0.0004 | 0.0001 | 0.0001 | 0.0001 | 0.0001 | 0.0001 |
| Tillage | ||||||
| Coulter chisel | 6 | 109 | 115 | 184 | 299 | 554 |
| Soil Spader | 6 | 122 | 129 | 170 | 299 | 492 |
| Probability | 0.97 | 0.25 | 0.23 | 0.35 | 0.98 | 0.10 |
| C. V. (%) | 171 | 37 | 31 | 29 | 22 | 17 |
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Table 54. Yield of carrots in a flat planted carrot study at the Oakes Irrigation Research Site. Comparison of hybrid, seeding rate, and tillage treatments - August harvest.
| Treatment | Yield of US #1 carrots (sorted by diameter) | Total yield | ||||
| > 1½" | 1 to 1½ " | > 1" | ¾ to 1" | total | ||
| tons/acre | ||||||
| Hybrid | ||||||
| Bolero | 1.7 | 11.8 | 13.5 | 7.1 | 20.6 | 28.4 |
| Prime Cut | 0.7 | 7.4 | 8.1 | 6.5 | 14.6 | 22.8 |
Probability |
0.15 | 0.012 | 0.011 | 0.10 | 0.013 | 0.005 |
| Seeding rate | ||||||
| 0.5 million | 3.5 a | 9.5 b | 13.0 a | 3.0 c | 16.1 c | 23.6 b |
| 1.0 million | 0.7 b | 12.3 a | 13.0 a | 7.3 b | 20.3 a | 27.8 a |
| 1.5 million | 0.4 b | 9.8 b | 10.2 b | 8.2 ab | 18.4 b | 27.0 a |
| 2.0 million | 0.1 b | 6.8 c | 6.9 c | 8.7 a | 15.6 c | 24.2 b |
Probability |
0.0003 | 0.0001 | 0.0001 | 0.0001 | 0.0001 | 0.0001 |
| Tillage | ||||||
| Coulter chisel | 1.1 | 8.6 | 9.7 | 6.9 | 16.6 | 25.4 |
| Soil Spader | 1.3 | 10.6 | 11.9 | 6.8 | 18.6 | 25.8 |
Probability |
0.81 | 0.09 | 0.08 | 0.83 | 0.10 | 0.68 |
| C. V. (%) | 178 | 27 | 20 | 25 | 13 | 8 |
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Table 55. Quality of carrots in a flat planted carrot study at the Oakes Irrigation Research Site. Comparison of hybrid, seeding rate, and tillage treatments - August harvest.
| Treatment | US #1 > 1" | Total US #1 | Multiple root | Root size | Root length | Root diameter |
| % | oz/root | inches | ||||
| Hybrid | ||||||
| Bolero | 46 | 72 | 12 | 2.0 | 8.8 | 1.09 |
| Prime Cut | 35 | 64 | 17 | 2.3 | 9.4 | 1.03 |
| Probability | 0.02 | 0.06 | 0.14 | 0.002 | 0.10 | 0.03 |
| Seeding rate | ||||||
| 0.5 million | 54 a | 68 ab | 22 b | 3.3 a | 9.4 a | 1.10 a |
| 1.0 million | 45 b | 72 a | 12 a | 1.9 b | 9.1 ab | 1.06 ab |
| 1.5 million | 35 c | 68 ab | 12 a | 1.7 bc | 8.6 b | 1.06 ab |
| 2.0 million | 27 d | 63 b | 12 a | 1.6 c | 9.3 a | 1.01 b |
| Probability | 0.0001 | 0.04 | 0.0001 | 0.0001 | 0.02 | 0.04 |
| Tillage | ||||||
| Coulter chisel | 37 | 64 | 17 | 2.0 | 8.5 | 1.06 |
| Soil Spader | 43 | 71 | 12 | 2.2 | 9.7 | 1.06 |
| Probability | 0.06 | 0.02 | 0.08 | 0.09 | 0.002 | 0.89 |
| C. V. (%) | 23 | 14 | 39 | 16 | 8 | 7 |
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Table 56. Quantities of carrots in a flat planted carrot study at the Oakes Irrigation Research Site. Comparison of hybrid, seeding rate, and tillage treatments - September harvest.
| Treatment | Number of US #1 carrots (sorted by diameter) | Total roots | ||||
| > 1½" | 1 to 1½ " | > 1" | ¾ to 1" | total | ||
| 1000s of roots/acre | ||||||
| Hybrid | ||||||
| Bolero | 45 | 199 | 244 | 160 | 404 | 548 |
| Prime Cut | 24 | 133 | 157 | 132 | 289 | 418 |
| Probability | 0.04 | 0.009 | 0.003 | 0.09 | 0.0006 | 0.005 |
| Seeding rate | ||||||
| 0.5 million | 74 a | 87 c | 161 b | 22 c | 183 c | 243 c |
| 1.0 million | 35 b | 197 a | 232 a | 131 b | 363 b | 478 b |
| 1.5 million | 25 b | 217 a | 242 a | 201 a | 443 a | 590 a |
| 2.0 million | 4 c | 163 b | 168 b | 231 a | 399 ab | 622 a |
| Probability | 0.0001 | 0.0001 | 0.0001 | 0.0001 | 0.0001 | 0.0001 |
| Tillage | ||||||
| Coulter chisel | 34 | 159 | 193 | 152 | 345 | 499 |
| Soil Spader | 35 | 173 | 208 | 140 | 349 | 467 |
| Probability | 0.86 | 0.35 | 0.09 | 0.52 | 0.87 | 0.36 |
| C. V. (%) | 46 | 20 | 17 | 34 | 20 | 15 |
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Table 57. Yield of carrots in a flat planted carrot study at the Oakes Irrigation Research Site. Comparison of hybrid, seeding rate, and tillage treatments - September harvest.
| Treatment | Yield of US #1 carrots (sorted by diameter) | Total yield | ||||
| > 1½" | 1 to 1½ " | > 1" | ¾ to 1" | total | ||
| tons/acre | ||||||
| Hybrid | ||||||
| Bolero | 7.3 | 14.7 | 22.0 | 5.1 | 27.1 | 35.5 |
| Prime Cut | 5.2 | 12.4 | 17.7 | 4.9 | 22.6 | 31.8 |
Probability |
0.09 | 0.20 | 0.03 | 0.75 | 0.008 | 0.02 |
| Seeding rate | ||||||
| 0.5 million | 15.0 a | 9.3 c | 24.3 a | 0.8 d | 25.1 a | 34.4 a |
| 1.0 million | 5.6 b | 16.0 a | 21.6 ab | 4.5 c | 26.1 a | 34.9 a |
| 1.5 million | 3.7 b | 16.1 a | 19.8 b | 6.6 b | 26.4 a | 34.4 a |
| 2.0 million | 0.7 c | 13.0 b | 13.7 c | 8.1 a | 21.9 b | 31.0 b |
Probability |
0.0001 | 0.0001 | 0.0001 | 0.0001 | 0.007 | 0.013 |
| Tillage | ||||||
| Coulter chisel | 6.2 | 12.7 | 18.9 | 4.9 | 23.8 | 33.5 |
| Soil Spader | 6.4 | 14.4 | 20.8 | 5.1 | 25.9 | 33.8 |
Probability |
0.89 | 0.14 | 0.0099 | 0.74 | 0.004 | 0.53 |
| C. V. (%) | 47 | 19 | 18 | 32 | 15 | 10 |
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Table 58. Quality of carrots in a flat planted carrot study at the Oakes Irrigation Research Site. Comparison of hybrid, seeding rate, and tillage treatments - September harvest.
| Treatment | US #1 > 1" | Total US #1 | Multiple root | Root size | Root length | Root diameter |
| % | oz/root | inches | ||||
| Hybrid | ||||||
| Bolero | 61 | 76 | 11 | 2.4 | 8.4 | 1.13 |
| Prime Cut | 55 | 71 | 15 | 3.1 | 9.2 | 1.11 |
| Probability | 0.15 | 0.03 | 0.005 | 0.03 | 0.03 | 0.65 |
| Seeding rate | ||||||
| 0.5 million | 70 a | 72 | 19 b | 4.7 a | 8.9 | 1.19 a |
| 1.0 million | 62 b | 75 | 12 a | 2.5 b | 8.9 | 1.13 ab |
| 1.5 million | 57 b | 77 | 9 a | 2.0 c | 8.5 | 1.09 b |
| 2.0 million | 44 c | 70 | 12 a | 1.8 c | 8.9 | 1.08 b |
| Probability | 0.0001 | 0.09 | 0.0001 | 0.0001 | 0.39 | 0.004 |
| Tillage | ||||||
| Coulter chisel | 56 | 71 | 15 | 2.7 | 8.6 | 1.13 |
| Soil Spader | 61 | 76 | 11 | 2.8 | 9.0 | 1.12 |
| Probability | 0.002 | 0.015 | 0.03 | 0.39 | 0.01 | 0.79 |
| C. V. (%) | 11 | 10 | 42 | 20 | 10 | 8 |
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Table 59. Quantities of carrots in a tillage by seeding rate study at the Oakes Irrigation Research Site. Comparison of hybrid, seeding rate, and tillage treatments - August harvest.
| Treatment | Number of US #1 carrots (sorted by diameter) | Total roots | ||||
| > 1½" | 1 to 1½ " | > 1" | ¾ to 1" | total | ||
| 1000s of roots/acre | ||||||
| Hybrid | ||||||
| Bolero | 2 | 158 | 160 | 240 | 400 | 650 |
| Prime Cut | 1 | 72 | 72 | 163 | 236 | 482 |
| Probability | 0.14 | 0.006 | 0.006 | 0.007 | 0.003 | 0.007 |
| Seeding rate | ||||||
| 1.0 million | 2 | 122 | 124 | 180 | 304 | 499 |
| 1.5 million | 1 | 108 | 108 | 223 | 332 | 634 |
| Probability | 0.06 | 0.03 | 0.02 | 0.0006 | 0.06 | 0.0001 |
| Tillage/rows | ||||||
| Disked + Bed, 2 rows | 1 bc | 94 c | 95 c | 177 | 272 c | 523 |
| Disked + Bed, 3 rows | 1 c | 108 bc | 109 c | 218 | 327 ab | 539 |
| Chisel + Bed, 2 rows | 0 c | 95 c | 96 c | 182 | 278 bc | 569 |
| Chisel + Bed, 3 rows | 0 c | 104 c | 104 c | 212 | 316 abc | 601 |
| Chisel, No Bed | 3 ab | 131 b | 134 b | 220 | 354 a | 625 |
| Soil Spader, No Bed | 4 a | 156 a | 161 a | 199 | 360 a | 541 |
| Probability | 0.0002 | 0.0001 | 0.0001 | 0.18 | 0.0013 | 0.09 |
| C. V. (%) | 94 | 23 | 19 | 36 | 22 | 19 |
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Table 60. Yield of carrots in a tillage by seeding rate study at the Oakes Irrigation Research Site. Comparison of hybrid, seeding rate, and tillage treatments - August harvest.
| Treatment | Yield of US #1 carrots (sorted by diameter) | Total yield | ||||
| > 1½" | 1 to 1½ " | > 1" | ¾ to 1" | total | ||
| tons/acre | ||||||
| Hybrid | ||||||
| Bolero | 0.3 | 12.2 | 12.6 | 8.2 | 20.8 | 30.2 |
| Prime Cut | 0.2 | 6.5 | 6.7 | 7.1 | 13.8 | 22.7 |
| Probability | 0.18 | 0.012 | 0.013 | 0.07 | 0.01 | 0.004 |
| Seeding rate | ||||||
| 1.0 million | 0.4 | 10.4 | 10.8 | 7.0 | 17.8 | 26.6 |
| 1.5 million | 0.2 | 8.3 | 8.5 | 8.3 | 16.8 | 26.4 |
| Probability | 0.049 | 0.0001 | 0.0001 | 0.001 | 0.10 | 0.76 |
| Tillage/rows | ||||||
| Disked + Bed, 2 rows | 0.2 bc | 8.3 b | 8.5 bc | 6.9 | 15.4 c | 25.4 |
| Disked + Bed, 3 rows | 0.1 bc | 9.2 b | 9.3 bc | 8.4 | 17.7 b | 26.1 |
| Chisel + Bed, 2 rows | 0.0 c | 8.4 b | 8.5 bc | 7.1 | 15.6 c | 26.5 |
| Chisel + Bed, 3 rows | 0.0 c | 8.3 b | 8.3 c | 8.0 | 16.3 bc | 26.3 |
| Chisel, No Bed | 0.5 ab | 9.5 b | 10.0 b | 7.8 | 17.8 b | 27.1 |
| Soil Spader, No Bed | 0.7 a | 12.5 a | 13.2 a | 7.7 | 20.9 a | 27.6 |
| Probability | 0.0006 | 0.0001 | 0.0001 | 0.32 | 0.0001 | 0.24 |
| C. V. (%) | 175 | 23 | 23 | 25 | 16 | 10 |
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Table 61. Quality of carrots in a tillage by seeding rate study at the Oakes Irrigation Research Site. Comparison of hybrid, seeding rate, and tillage treatments - August harvest.
| Treatment | US #1 > 1" | Total US #1 | Multiple root | Root size | Root length | Root diameter | Straight score† |
| % | oz/root | inches | 1 to 10 | ||||
| Hybrid | |||||||
| Bolero | 41 | 69 | 14 | 1.7 | 8.6 | 1.09 | 5.8 |
| Prime Cut | 28 | 61 | 19 | 1.9 | 9.3 | 1.01 | 5.8 |
Probability |
0.04 | 0.07 | 0.24 | 0.11 | 0.001 | 0.02 | 0.82 |
| Seeding rate | |||||||
| 1.0 million | 39 | 66 | 17 | 1.9 | 8.9 | 1.05 | 5.8 |
| 1.5 million | 30 | 63 | 15 | 1.7 | 8.9 | 1.04 | 5.8 |
Probability |
0.0001 | 0.03 | 0.12 | 0.0001 | 0.94 | 0.63 | 0.67 |
| Tillage/rows | |||||||
| Disked + Bed, 2 rows | 32 b | 61 cd | 21 c | 1.9 | 9.0 b | 1.06 | 6.0 |
| Disked + Bed, 3 rows | 34 b | 67 b | 19 c | 1.8 | 8.7 b | 1.03 | 5.9 |
| Chisel + Bed, 2 rows | 31 b | 58 d | 18 bc | 1.9 | 8.9 b | 1.04 | 5.7 |
| Chisel + Bed, 3 rows | 31 b | 62 bcd | 16 bc | 1.7 | 9.2 ab | 1.03 | 5.8 |
| Chisel, No Bed | 35 b | 65 bc | 14 ab | 1.7 | 8.1 c | 1.06 | 5.6 |
| Soil Spader, No Bed | 45 a | 75 a | 10 a | 1.9 | 9.6 a | 1.07 | 5.7 |
Probability |
0.0001 | 0.0001 | 0.0001 | 0.06 | 0.001 | 0.83 | 0.23 |
| C. V. (%) | 20 | 10 | 37 | 14 | 8 | 9 | 8 |
†Straight score indicates how straight the carrots were. 1 is very crooked, 10 is perfectly straight.
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Table 62. Quantities of carrots in a tillage by seeding rate study at the Oakes Irrigation Research Site. Comparison of hybrid, seeding rate, and tillage treatments - September harvest.
| Treatment | Number of US #1 carrots (sorted by diameter) | Total roots | ||||
| > 1½" | 1 to 1½ " | > 1" | ¾ to 1" | total | ||
| 1000s of roots/acre | ||||||
| Hybrid | ||||||
| Bolero | 28 | 226 | 254 | 167 | 421 | 560 |
| Prime Cut | 9 | 141 | 150 | 135 | 285 | 410 |
Probability |
0.02 | 0.002 | 0.003 | 0.045 | 0.005 | 0.002 |
| Seeding rate | ||||||
| 1.0 million | 23 | 185 | 209 | 124 | 332 | 448 |
| 1.5 million | 14 | 182 | 195 | 178 | 374 | 522 |
Probability |
0.009 | 0.68 | 0.09 | 0.0001 | 0.013 | 0.0003 |
| Tillage/rows | ||||||
| Disked + Bed, 2 rows | 14 b | 160 c | 173 b | 152 | 325 b | 455 bc |
| Disked + Bed, 3 rows | 16 b | 171 bc | 187 b | 134 | 322 b | 436 c |
| Chisel + Bed, 2 rows | 10 b | 168 c | 179 b | 136 | 315 b | 462 bc |
| Chisel + Bed, 3 rows | 11 b | 188 abc | 199 b | 153 | 352 ab | 491 abc |
| Chisel, No Bed | 29 a | 199 ab | 228 a | 180 | 408 a | 558 a |
| Soil Spader, No Bed | 31 a | 215 a | 246 a | 151 | 397 a | 510 ab |
Probability |
0.002 | 0.004 | 0.0001 | 0.21 | 0.002 | 0.007 |
| C. V. (%) | 94 | 23 | 19 | 36 | 22 | 19 |
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Table 63. Yield of carrots in a tillage by seeding rate study at the Oakes Irrigation Research Site. Comparison of hybrid, seeding rate, and tillage treatments - September harvest.
| Treatment | Yield of US #1 carrots (sorted by diameter) | Total yield | ||||
| > 1½" | 1 to 1½ " | > 1" | ¾ to 1" | total | ||
| tons/acre | ||||||
| Hybrid | ||||||
| Bolero | 4.3 | 17.0 | 21.4 | 5.3 | 26.6 | 35.5 |
| Prime Cut | 2.0 | 13.9 | 15.9 | 5.3 | 21.2 | 30.4 |
Probability |
0.06 | 0.08 | 0.06 | 0.94 | 0.07 | 0.054 |
| Seeding rate | ||||||
| 1.0 million | 4.1 | 16.3 | 20.4 | 4.5 | 24.9 | 34.0 |
| 1.5 million | 2.2 | 14.7 | 16.8 | 6.1 | 22.9 | 31.9 |
Probability |
0.002 | 0.02 | 0.0001 | 0.0001 | 0.02 | 0.013 |
| Tillage/rows | ||||||
| Disked + Bed, 2 rows | 2.7 ab | 14.0 | 16.7 c | 5.4 | 22.1 c | 31.3 |
| Disked + Bed, 3 rows | 2.9 ab | 15.2 | 18.1 bc | 4.8 | 22.8 bc | 31.8 |
| Chisel + Bed, 2 rows | 2.0 b | 15.5 | 17.6 bc | 5.0 | 22.6 c | 33.2 |
| Chisel + Bed, 3 rows | 2.0 b | 16.0 | 18.0 bc | 5.4 | 23.5 bc | 32.2 |
| Chisel, No Bed | 4.7 a | 15.0 | 19.7 ab | 5.7 | 25.4 ab | 34.4 |
| Soil Spader, No Bed | 4.7 a | 17.1 | 21.7 a | 5.4 | 27.2 a | 34.9 |
Probability |
0.03 | 0.15 | 0.0013 | 0.75 | 0.003 | 0.09 |
| C. V. (%) | 93 | 21 | 18 | 35 | 16 | 12 |
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Table 64. Quality of carrots in a tillage by seeding rate study at the Oakes Irrigation Research Site. Comparison of hybrid, seeding rate, and tillage treatments - September harvest.
| Treatment | US #1 > 1" | Total US #1 |
Multiple root | Root size | Root length | Root diameter | Straight score† |
| % | oz/root | inches | 1 to 10 | ||||
| Hybrid | |||||||
| Bolero | 60 | 75 | 13 | 2.1 | 8.4 | 1.15 | 5.2 |
| Prime Cut | 52 | 70 | 17 | 2.5 | 9.3 | 1.09 | 5.2 |
Probability |
0.049 | 0.22 | 0.30 | 0.04 | 0.013 | 0.01 | 0.49 |
| Seeding rate | |||||||
| 1.0 million | 59 | 73 | 15 | 2.5 | 9.0 | 1.13 | 5.2 |
| 1.5 million | 52 | 72 | 14 | 2.0 | 8.7 | 1.11 | 5.1 |
Probability |
0.0001 | 0.51 | 0.41 | 0.0001 | 0.13 | 0.27 | 0.36 |
| Tillage/rows | |||||||
| Disked + Bed, 2 rows | 52 c | 70 bc | 18 b | 2.3 | 9.1 | 1.12 | 5.3 ab |
| Disked + Bed, 3 rows | 56 bc | 71 bc | 17 b | 2.3 | 8.8 | 1.13 | 4.9 c |
| Chisel + Bed, 2 rows | 53 bc | 67 c | 17 b | 2.4 | 8.8 | 1.13 | 5.0 bc |
| Chisel + Bed, 3 rows | 56 bc | 73 abc | 17 b | 2.2 | 8.9 | 1.12 | 5.3 ab |
| Chisel, No Bed | 57 ab | 74 ab | 11 a | 2.2 | 8.5 | 1.11 | 5.3 ab |
| Soil Spader, No Bed | 62 a | 78 a | 9 a | 2.3 | 8.9 | 1.10 | 5.4 a |
Probability |
0.002 | 0.012 | 0.0003 | 0.59 | 0.35 | 0.95 | 0.04 |
| C. V. (%) | 12 | 11 | 42 | 17 | 9 | 8 | 10 |
†Straight score indicates how straight the carrots were. 1 is very crooked, 10 is perfectly straight.
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Go to Oakes Irrigation Research Site 1999 annual report