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
HERBICIDE CARRYOVER STUDY, 1997
Richard Greenland
As vegetable production increases in North Dakota, vegetables will be planted in rotations with field corn and soybean. Many of the herbicides applied to corn and soybean could carry over and injure vegetable crops planted the next year. Chemical companies, recognizing this potential for injury, have placed rotation restrictions on their herbicide labels. These labels restrict planting vegetables for one to four years after applying the herbicide to corn or soybean. But little information is available to verify the need for such restrictions, especially on highly permeable, loam or sandy loam soils that are irrigated. This is the second study conducted at the Oakes Irrigation Research Station to determine herbicide injury to vegetables planted one year after applying certain herbicides to corn or soybean. In 1996, we applied Accent, Broadstrike + Dual, and Scorpion III to field corn, and Pursuit and Raptor to soybean. In 1997, we planted potatoes, cabbage, carrots, onions, tomatoes, and acorn squash in rotation with the field corn and soybean. The injury to and yield of the vegetables showed to what extent herbicide carryover affects these vegetables.
Table 37. Planting, seed preparation, and harvest date for herbicide carryover study
Table 38. Fertilizer rate and pest control for herbicide carryover study
Table 39. Response of cabbage to herbicides applied to field corn the previous year.
Table 40. Response of cabbage to herbicides applied to soybean the previous year.
Table 41. Response of carrots to herbicides applied to corn the previous year.
Table 42. Response of carrot to carryover herbicides applied to soybean the previous year.
Table 43. Response of onions to herbicides applied to corn the previous year.
Table 44. Response of onions to herbicides applied to soybean the previous year.
Table 47. Response of tomato to carryover of herbicides applied to corn the previous year.
Table 48. Response of tomato to carryover from herbicides applied to soybean the previous year.
Table 49. Responses of acorn squash to carryover from herbicides applied to corn the previous year.
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MATERIALS AND METHODS
| Soil: | Gardena loam, Embden loam, and Embden sandy loam; pH 7.3; 2.8% organic matter; soil-P and soil-K were very high; soil-S was low. |
| Previous Crops: | 1995 - edible beans, potato, onion, 1994 - field corn, cabbage. |
| Plots: | Plots were 7.5 ft. wide by 20 ft. long. The study had 4 reps. |
| Irrigation: | Overhead sprinkler irrigation as needed. |
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Table 37. Planting, seed preparation, and harvest date for herbicide carryover study
| Crop | Planting Date | Seedbed preparation | Harvest Date | |
| Date | Activity | |||
| Corn 1996 | May 23 | May 21 May 22 June 27 |
disked multiweed - twice cultivated |
Nov 12 to 14, 1996 |
| Soybean 1996 | May 23 | May 21 May 22 |
Disked Multiweed-twice |
Oct 16 |
| Cabbage 1997 | May 22 | May 9 May 15 |
disked multiweeded |
August 11 and 22, and Sept 10 and 26 |
| Carrot 1997 | May 27 | May 9 May 27 May 27 |
disked disked multiweed |
Oct17 |
| Onion 1997 | May 12 | May 9 May 9 |
disked multiweed |
Pulled Sep 25 & Oct 2 Bagged Oct 8 and 9 |
| Potato 1997 | May 21 | May 9 May 12 |
disked multiweeded |
Sept 25 and 26 |
| Tomato 1997 | June 17 | May 9 June 17 |
disked disked & multiweeded |
Sept 19 and 23 |
| Winter Squash 1997 | June 17 | May 9 June 17 |
disked disked |
Oct 6 |
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Table 38. Fertilizer rate and pest control for herbicide carryover study
| Crop | Fertilizer applications | Pest control | ||
| date | rate and fertilizer | date | pesticide/operation | |
| Corn 1996 | April 17 May 22 June 26 |
140 lbs 10-50-0 156 lbs 0-0-60 78 lbs 21-0-0-24 50 lbs N/acre as 28-0-0 100 lbs N/acre as 28-0-0 |
May 28 June 27 July 12, 31 |
Dual (1.9 pt/acre) on all but Broadstrike + Dual treatments cultivate Asana (8 oz/acre) |
| Soybean 1996 | April 17 | 140 lbs 10-50-0 156 lbs 0-0-60 78 lbs 21-0-0-24 |
May 22 May 28 July 12, 31 Aug 6 |
Treflan (1 pt/acre) Dual (1.9 pt/acre) on all but Broadstrike + Dual treatments. Asana (8 oz/acre) hand weeded |
| Cabbage 1997 | April 23 May 5 |
140 lbs 10-50-0 156 lbs 0-0-60 78 lbs 21-0-0-24 50 lbs N/acre as 28-0-0 |
May 15 June 5 June 13 July 10, 29, 30 July 15, 21, 28 Aug 4, 21, 28 |
Treflan (1 pt/acre) Dacthal (8 lbs/acre) Poast + Dash (1.5 + 2 pts/acre) hand weeded DiPel (1 lb/acre) DiPel (1 lb/acre) |
| Carrot 1997 | April 23 May 5 |
140 lbs 10-50-0 156 lbs 0-0-60 78 lbs 21-0-0-24 50 lbs N/acre as 28-0-0 |
May 27 July 9 July 14 Aug 20 |
Treflan (1.5 pt/acre) Lorox (3 lb/acre) Fusilade + nonionic surfactant (12 oz/acre + 8 oz/25 gal) Asana (8 oz/acre) |
| Onion 1997 | April 23 May 5 |
140 lbs 10-50-0 156 lbs 0-0-60 78 lbs 21-0-0-24 50 lbs N/acre as 28-0-0 |
June 4 June 19 July 10,17 Aug 5 Aug 20 |
Fusilade + Prowl + COC (12 oz/acre + 1.5 pt/acre + 1%) Buctril + Goal (1.5 and 0.6 pt/A) hand weeded Bravo (2 pt/acre) Dithane (2.2 qt/acre) |
| Potato 1997 | April 23 May 5 |
140 lbs 10-50-0 156 lbs 0-0-60 78 lbs 21-0-0-24 50 lbs N/acre as 28-0-0 |
June 6; 24 July 3 July 9 and 29 July 14 July 21 August 7 Aug 7 and 20 |
Drag off; hilling Provado (3.75 oz/acre) Pounce (8 oz and 6 oz/acre) Imidan (1.3 lbs/acre) Bravo (1.5 pt/acre) Asana (6 oz/acre) Dithane (1.5 qt/acre) |
| Tomato 1997 | April 23 May 5 |
140 lbs 10-50-0 156 lbs 0-0-60 78 lbs 21-0-0-24 50 lbs N/acre as 28-0-0 |
June 17 July 15 July 21&Aug 5 July 22&Aug 5 Aug 20 |
Treflan (1 pt/acre) Rimsulfuron (¼ oz/acre) Bravo (1.5 pt/acre) Asana (6 oz/acre) Asana+Dithane (8 oz+2.2 qt/A) |
| Winter Squash 1997 |
April 23 May 5 |
140 lbs 10-50-0 156 lbs 0-0-60 78 lbs 21-0-0-24 50 lbs N/acre as 28-0-0 |
July 10 August 5 |
hand weeded Asana (6 oz/acre) |
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Table 39. Response of cabbage to herbicides applied to field corn the previous year.
| Herbicide | Rate† | Crop injury | Number of heads | Yield | Days to harvest | Head size |
| % | tons/acres | lbs/head | ||||
| Accent | 1X | 9 | 6250 | 19.7 | 81 | 6.3 a |
| 2X | 31 | 6010 | 16.4 | 84 | 5.4 bc | |
| 4X | 51 | 6490 | 18.0 | 87 | 5.5 abc | |
| Broadstrike + Dual | 1X | 54 | 6370 | 15.3 | 84 | 4.7 c |
| 2X | 74 | 5770 | 10.9 | 89 | 3.7 d | |
| 4X | 85 | 3000 | 4.9 | 89 | 3.0 d | |
| Scorpion III | 1X | 31 | 6610 | 18.4 | 87 | 5.6 ab |
| 2X | 47 | 6490 | 16.5 | 84 | 5.0 bc | |
| 4X | 84 | 3720 | 7.0 | 89 | 3.6 d | |
| Check | 8 | 6730 | 18.8 | 81 | 5.5 abc | |
| LSD(0.05) | 15 | 1880 | 5.2 | NS | ‡ | |
| C.V.(%) | 22 | 23 | 25 | 6 | 12 | |
†Rate: 1X is the standard rate; 2X and 4X are 2 and 4 times
the standard rate. (1X rates were: Accent - 0.67 oz/acre; Broadstrike
+ Dual - 2 pt/acre; and Scorpion III - 0.25 lbs)
‡Values in this column followed by the same letter are not
significantly different at the 0.05 level.
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Table 40. Response of cabbage to herbicides applied to soybean the previous year.
| Herbicide | Rate† | Crop injury | Number of heads | Yield | Days to harvest | Head size |
| % | tons/acre | Ibs/head | ||||
| Pursuit | 1X | 18 b‡ | 6310 | 19.6 | 81 | 6.2 |
| 2X | 63 c | 6490 | 17.4 | 81 | 5.4 | |
| 4X | 65 c | 7190 | 19.7 | 85 | 5.5 | |
| Raptor | 1X | 8 ab | 6680 | 17.8 | 81 | 5.4 |
| 2X | 9 ab | 7330 | 20.8 | 81 | 5.7 | |
| 4X | 4 a | 7090 | 21.7 | 81 | 6.2 | |
| Check | 6 ab | 7340 | 22.8 | 81 | 6.2 | |
| C.V.(%) | 37 | 9 | 12 | 2 | 13 | |
†Rate: 1X is the standard rate; 2X and 4X are 2 and 4 times
the standard rate (1X rates were: Pursuit - 4 oz/acre; Raptor - 4 oz/acre).
‡Values in this column followed by the same letter are not
significantly different at the 0.05 level.Values in columns without letters
are not significantly different from other values in the same column.
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Table 41. Response of carrots to herbicides applied to corn the previous year.
| Herbicide | Rate† | Crop injury | Number of roots | Yield | Root size |
| % | 1000s/acre | tons/acre | oz/root | ||
| Accent | 1X | 40 | 176 | 29.7 | 5.3 |
| 2X | 20 | 197 | 33.0 | 5.3 | |
| 4X | 30 | 150 | 25.4 | 5.2 | |
| Broadstrike + Dual | 1X | 10 | 152 | 23.9 | 5.1 |
| 2X | 20 | 158 | 28.1 | 5.0 | |
| 4X | 70 | 176 | 28.7 | 4.8 | |
| Scorpion III | 1X | 0 | 166 | 26.6 | 4.9 |
| 2X | 20 | 131 | 25.8 | 5.4 | |
| 4X | 10 | 174 | 28.9 | 5.3 | |
| Check | 10 | 173 | 28.8 | 5.3 | |
| LSD(0.05) | ‡ | NS | NS | NS | |
| C.V.(%) | ‡ | 20 | 16 | 11 | |
†Rate: 1X is the standard rate; 2X and 4X are 2 and 4 times
the standard rate. (1X rates were: Accent - 0.67 oz/acre; Broadstrike
+ Dual - 2 pt/acre; and Scorpion III - 0.25 lbs)
‡Single observations. No statistics possible.
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Table 42. Response of carrot to carryover herbicides applied to soybean the previous year.
| Herbicide | Rate† | Crop injury | Number of roots | Yield | Root size |
| % | 1000s/acre | tons/acre | oz/root | ||
| Pursuit | 1X | 10 | 89 | 15.0 | 4.9 |
| 2X | 25 | 133 | 22.0 | 4.9 | |
| 4X | 50 | 115 | 20.7 | 4.8 | |
| Raptor | 1X | 0 | 150 | 24.9 | 4.6 |
| 2X | 0 | 126 | 24.3 | 5.4 | |
| 4X | 10 | 133 | 23.8 | 5.4 | |
| Check | 10 | 130 | 23.7 | 4.5 | |
| LSD(0.05) | ‡ | NS | NS | NS | |
| C.V.(%) | ‡ | 21 | 32 | 16 | |
†Rate: 1X is the standard rate; 2X and 4X are 2 and 4 times
the standard rate (1X rates were: Pursuit - 4 oz/acre; Raptor - 4 oz/acre).
‡Single observations. No statistics possible.
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Table 43. Response of onions to herbicides applied to corn the previous year.
| Herbicide | Rate† | Crop injury | Bulb size | Single centers | Number of bulbs (given by size) |
Yield (given by size) |
||||
| >3" | 2 to 3" | total | >3" | 2 to 3" | total | |||||
| % | oz/bulb | % | -------- 1000s/acre ------- | --------- cwt/acre --------- | ||||||
| Accent | 1X | 15 | 7.7 | 15 | 52 | 52 | 137 | 323 | 172 | 558 |
| 2X | 35 | 6.6 | 25 | 20 | 37 | 126 | 121 | 118 | 330 | |
| 4X | 55 | 6.5 | 5 | 16 | 36 | 100 | 95 | 112 | 262 | |
| Broadstrike + Dual | 1X | 5 | 7.1 | 0 | 41 | 57 | 131 | 246 | 188 | 498 |
| 2X | 5 | 7.2 | 30 | 41 | 57 | 129 | 248 | 189 | 497 | |
| 4X | 8 | 8.2 | 5 | 58 | 44 | 132 | 372 | 153 | 587 | |
| Scorpion III | 1X | 3 | 7.2 | 5 | 40 | 46 | 127 | 255 | 151 | 480 |
| 2X | 0 | 7.0 | 15 | 40 | 59 | 121 | 238 | 194 | 475 | |
| 4X | 3 | 7.5 | 15 | 43 | 53 | 124 | 274 | 175 | 503 | |
| Check | 0 | 6.5 | 35 | 31 | 70 | 139 | 188 | 231 | 480 | |
| LSD(0.05) | 10 | NS | NS | 22 | 19 | NS | 148 | 61 | 136 | |
| C.V.(%) | 54 | 11 | 105 | 40 | 25 | 15 | 43 | 25 | 20 | |
†Rate: 1X is the standard rate; 2X and 4X are 2 and 4 times the standard rate. (1X rates were: Accent - 0.67 oz/acre; Broadstrike + Dual - 2 pt/acre; and Scorpion III - 0.25 lbs)
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Table 44. Response of onions to herbicides applied to soybean the previous year.
| Herbicide | Rate† | Crop injury | Bulb size | Single centers | Number of bulbs (given by size) |
Yield (given by size) |
||||
| >3" | 2 to 3" | total | >3" | 2 to 3" | total | |||||
| % | oz/bulb | % | ---------1000s/acre -------- | --------- cwt/acre -------- | ||||||
| Pursuit | 1X | 5 ab | 6.2 | 50 a | 32 | 92 | 167 | 180 | 302 | 554 |
| 2X | 16 b | 6.4 | 26 ab | 32 | 72 | 156 | 184 | 234 | 501 | |
| 4X | 30 c | 6.2 | 10 b | 27 | 60 | 139 | 154 | 195 | 428 | |
| Raptor | 1X | 5 ab | 6.0 | 30 ab | 25 | 78 | 154 | 142 | 255 | 487 |
| 2X | 13 b | 6.5 | 20 b | 35 | 80 | 163 | 204 | 267 | 556 | |
| 4X | 8 ab | 6.6 | 30 ab | 40 | 73 | 152 | 233 | 243 | 549 | |
| Check | 0 a | 6.4 | 10 b | 33 | 90 | 164 | 195 | 297 | 561 | |
| LSD(0.05) | ‡ | NS | ‡ | NS | NS | NS | NS | NS | NS | |
| C.V.(%) | 76 | 6 | 59 | 31 | 21 | 12 | 33 | 29 | 17 | |
†Rate: 1X is the standard rate; 2X and 4X are 2 and 4 times
the standard rate (1X rates were: Pursuit - 4 oz/acre; Raptor - 4 oz/acre).
‡Values in the same column followed by the same letter are
not significantly different at the 0.05 level.
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Table 45. Number, yield, and size of potatoes grown one year after application of herbicides to field corn.
| Herbicide | Rate† | Number of potatoes | Potato yield | Tuber size |
| 1000s/acre | cwt/acre | oz/tuber | ||
| Accent | 1X | 32.1 | 159 | 7.8 ab‡ |
| 2X | 36.3 | 118 | 5.2 d | |
| 4X | 43.3 | 232 | 8.9 a | |
| Broadstrike + Dual | 1X | 40.2 | 168 | 6.6 bcd |
| 2X | 37.5 | 178 | 7.6 abc | |
| 4X | 34.8 | 136 | 6.3 bcd | |
| Scorpion III | 1X | 34.2 | 148 | 6.9 bcd |
| 2X | 41.7 | 180 | 7.0 bc | |
| 4X | 38.4 | 179 | 7.6 abc | |
| Check | 57.4 | 212 | 5.9 c | |
| C.V.(%) | 29 | 30 | 17 | |
†Rate: 1X is the standard rate; 2X and 4X are 2 and 4 times
the standard rate. (1X rates were: Accent - 0.67 oz/acre; Broadstrike
+ Dual - 2 pt/acre; and Scorpion III - 0.25 lbs)
‡Values in this column followed by the same letter are not
significantly different at the 0.05 level.There were no significant differences
at the 0.01 level. Values in columns without letters are not significantly
different from other values in the same column.
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Table 46. Number, yield, and size of potatoes grown one year after application of herbicides to soybean.
| Herbicide | Rate† | Number of potatoes | Potato yield | Tuber size |
| 1000s/acre | cwt/acre | oz/tuber | ||
| Pursuit | 1X | 58.7 | 307 bc2 | 8.7 |
| 2X | 75.0 | 414 a | 9.1 | |
| 4X | 57.8 | 311 bc | 8.6 | |
| Raptor | 1X | 52.0 | 257 c | 8.0 |
| 2X | 43.4 | 238 c | 9.0 | |
| 4X | 72.9 | 358 ab | 8.2 | |
| Check | 58.4 | 341 abc | 9.3 | |
| C.V.(%) | 29 | 21 | 15 | |
†Rate: 1X is the standard rate; 2X and 4X are 2 and 4 times
the standard rate (1X rates were: Pursuit - 4 oz/acre; Raptor - 4 oz/acre).
‡Values in this column followed by the same letter are not
significantly different at the 0.05 level.There were no significant differences
at the 0.01 level. Values in columns without letters are not significantly
different from other values in the same column.
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Table 47. Response of tomato to carryover of herbicides applied to corn the previous year.
| Herbicide | Rate† | Early injury | Percent red | Tomato yield | Fruit size | |||
| red | green | total | red | green | ||||
| % | % | ----------- tons/acre --------- | ----- oz/fruit ----- | |||||
| Accent | 1X | 8 | 16 | 7.2 | 37.4 | 44.6 | 3.2 | 3.0 |
| 2X | 0 | 16 | 7.4 | 38.6 | 46.0 | 3.2 | 2.7 | |
| 4X | 3 | 14 | 6.4 | 40.1 | 46.5 | 3.4 | 2.8 | |
| Broadstrike + Dual | 1X | 8 | 15 | 6.7 | 38.2 | 44.9 | 3.2 | 3.1 |
| 2X | 5 | 14 | 6.9 | 41.2 | 48.1 | 3.1 | 2.8 | |
| 4X | 13 | 18 | 8.8 | 39.5 | 48.3 | 3.2 | 3.0 | |
| Scorpion III | 1X | 3 | 19 | 8.5 | 36.2 | 44.7 | 3.4 | 2.8 |
| 2X | 3 | 20 | 8.8 | 36.6 | 45.4 | 3.1 | 2.9 | |
| 4X | 10 | 20 | 9.1 | 35.0 | 44.1 | 3.2 | 2.9 | |
| Check | 0 | 16 | 7.7 | 39.8 | 47.4 | 3.4 | 3.0 | |
| LSD(0.05) | 7 | NS | NS | NS | NS | NS | NS | |
| C.V.(%) | 101 | 33 | 34 | 13 | 10 | 10 | 10 | |
†Rate: 1X is the standard rate; 2X and 4X are 2 and 4 times the standard rate. (1X rates were: Accent - 0.67 oz/acre; Broadstrike + Dual - 2 pt/acre; and Scorpion III - 0.25 lbs)
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Table 48. Response of tomato to carryover from herbicides applied to soybean the previous year.
| Herbicide | Rate† | Early injury | Percent red | Tomato yield | Fruit size | |||
| red | green | total | red | green | ||||
| % | % | ----------- tons/acre --------- | ----- oz/fruit ----- | |||||
| Pursuit | 1X | 8 | 10 | 4.6 | 38.7 | 43.2 | 3.1 | 2.8 |
| 2X | 25 | 1 | 0.6 | 33.5 | 34.1 | ---‡ | 2.7 | |
| 4X | 43 | 0 | 0.0 | 20.3 | 20.4 | ---‡ | 2.3 | |
| Raptor | 1X | 0 | 15 | 6.6 | 37.5 | 44.1 | 3.3 | 3.0 |
| 2X | 8 | 14 | 5.6 | 34.7 | 40.3 | 3.3 | 2.6 | |
| 4X | 8 | 11 | 4.6 | 39.8 | 44.3 | 3.1 | 2.7 | |
| Check | 0 | 11 | 4.7 | 39.5 | 44.2 | 2.9 | 2.7 | |
| LSD (0.05) | 8 | 4 | 1.6 | 7.7 | 7.6 | NS | 0.3 | |
| C.V.(%) | 42 | 31 | 28 | 15 | 13 | 24 | 8 | |
†Rate: 1X is the standard rate; 2X and 4X are 2 and 4 times
the standard rate (1X rates were: Pursuit - 4 oz/acre; Raptor - 4 oz/acre).
‡Too few red tomatoes to calculate average fruit size.
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Table 49. Responses of acorn squash to carryover from herbicides applied to corn the previous year.
| Herbicide | Rate† | Early injury‡ | Early stand‡ | Weed control§ | Fruit size | Number of fruit | Yield | ||
| marketable | total | marketable | total | ||||||
| % | plants/plot | % | lbs/fruit | -----1000s/acre ---- | ----- tons/acre ---- | ||||
| Accent | 1X | 15 ab¶ | 8.3 | 43 cd | 2.0 a | 8.0 | 9.1 a | 8.1 ab | 8.6 a |
| 2X | 13 ab | 8.5 | 55 ab | 1.9 ab | 8.8 | 10.1 a | 8.4 a | 8.8 a | |
| 4X | 18 b | 7.5 | 60 a | 1.9 b | 8.0 | 8.6 ab | 7.4 abc | 7.8 ab | |
| Broadstrike + Dual | 1X | 18 b | 10.0 | 50 bc | 1.8 bc | 8.0 | 8.9 ab | 7.2 abc | 7.8 ab |
| 2X | 23 bc | 9.0 | 50 bc | 1.8 bc | 7.1 | 7.9 ab | 6.3 bc | 6.9 ab | |
| 4X | 45 d | 8.3 | 60 a | 1.3 d | 5.2 | 5.6 c | 3.4 d | 3.6 c | |
| Scorpion III | 1X | 10 ab | 7.8 | 43 cd | 1.8 bc | 8.4 | 8.8 ab | 7.4 abc | 7.7 ab |
| 2X | 18 bc | 8.5 | 48 bcd | 1.8 bc | 8.0 | 8.6 ab | 7.1 abc | 7.5 ab | |
| 4X | 33 cd | 8.5 | 50 bc | 1.7 c | 6.4 | 7.1 b | 5.4 cd | 5.8 b | |
| Check | 3 a | 9.3 | 40 d | 1.9 ab | 7.7 | 9.7 a | 7.1 abc | 8.2 a | |
| C.V.(%) | 51 | 18 | 13 | 7 | 20 | 17 | 21 | 19 | |
†Rate: 1X is the standard rate; 2X and 4X are 2 and 4 times
the standard rate. (1X rates were: Accent - 0.67 oz/acre; Broadstrike
+ Dual - 2 pt/acre; and Scorpion III - 0.25 lbs)
‡Injury, plant stand, and weed control ratings were taken
on 10 July 1997.
§Rating is percent of plot free of weeds.
¶Values in the same column followed by the same letter are
not significantly different at the 0.05 level.
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Table 50. Responses of acorn squash to carryover from herbicides applied to soybean the previous year.
| Herbicide | Rate† | Early injury‡ | Early stand‡ | Weed control§ | Fruit size | Number of fruit | Yield | ||
| marketable | total | marketable | total | ||||||
| % | plants/plot | % | lbs/fruit | -----1000s/acre ---- | ----- tons/acre ---- | ||||
| Pursuit | 1X | 25 | 5.0 | 60 b | 1.8 | 5.8 | 6.6 | 5.3 | 5.9 |
| 2X | 5 | 9.0 | 62 b | 1.8 | 9.6 | 10.4 | 8.8 | 9.5 | |
| 4X | 15 | 7.5 | 75 a | 1.9 | 8.8 | 10.3 | 8.4 | 9.5 | |
| Raptor | 1X | 10 | 6.3 | 53 bc | 1.8 | 8.2 | 8.8 | 7.5 | 8.0 |
| 2X | 13 | 8.0 | 53 bc | 1.9 | 7.6 | 8.3 | 7.3 | 8.1 | |
| 4X | 10 | 3.0 | 55 bc | 1.7 | 4.5 | 4.9 | 3.8 | 4.0 | |
| Check | 13 | 6.0 | 48 c | 1.9 | 7.3 | 7.7 | 7.1 | 7.5 | |
| C.V.(%) | 79 | 44 | 12 | 6 | 26 | 27 | 24 | 25 | |
| LSD(0.05) | NS | NS | ¶ | NS | 2.8 | 3.3 | 2.4 | 2.8 | |
†Rate: 1X is the standard rate; 2X and 4X are 2 and 4 times
the standard rate (1X rates were: Pursuit - 4 oz/acre; Raptor - 4 oz/acre).
‡Injury, plant stand, and weed control ratings taken on 10
July 1997.
§Rating is percent of plot free of weeds.
¶Values in this column followed by the same letter are not
significantly different at the 0.05 level.
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RESULTS
Carryover Accent injured cabbage and onion. Carryover Broadstrike injured carrot, cabbage, and squash. Carryover Scorpion III injured cabbage and squash. Carryover Pursuit injured carrot, cabbage, onion, tomato. Carryover Raptor injured carrot and squash. There was no visible injury to potato from carryover of any of the herbicides tested. Soil properties and abundant moisture probably helped reduce crop injury. After additional research for verification, labels could be changed to allow rotation of many vegetables at shorter intervals, especially under irrigation and on light textured soils.
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Go to Oakes Irrigation Research Site weed control studies page
Go to Oakes Irrigation Research Site rotation studies page
Go to Oakes Irrigation Research Site 1997 annual report