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
Richard Greenland
Table 68. Treatment application data
Table 69. Onion weed control treatments
Table 70. Barley cover crop injury, onion injury, and redroot pigweed ratings
Table 71. Common lambsquarters and hairy nightshade weed control
Table 72. Onion yields and total number of bulbs
Weed control is difficult in onions because onions do not compete well with weeds and few herbicides are available for onion production. Late emerging weeds are not shaded by the onions and grow vigorously. Although late emerging weeds do not reduce yield much, they interfere with harvest. In this experiment we looked at several new herbicides and herbicide combinations for use in onions, along with some new application timings for labeled herbicides.
MATERIALS AND METHODS
Soil: |
Egeland loam; pH=6.9; 2.2% organic matter; soil-P and soil-K were very high; soil-S was low. |
Previous crops: |
2002 - sweetcorn and potato; 2001 - edible bean, potato and sugar beet; 2000 - winter squash, pumpkin and field corn. |
Seedbed preparation: |
Disked on April 11. Multiweeded (field cultivated) on April to incorporate fertilizer and smooth the seedbed. |
Planting: |
Direct seeded Teton onions (175,000 seeds/acre) on April 22 with a Monosem precision planter set to plant a barley cover crop (0.45 bu/acre, 18-inch rows) between and parallel to the onion rows. Onions were planted in paired rows (2.5" apart), with the paired rows on 18" centers. |
Plots: |
Plots were 17 ft long by 6 ft wide with a 2-ft border between plots. The study had 4 reps. |
Fertilizer: |
On April 9, broadcast 11 lbs N/acre and 52 lbs P205 as 11-52-0, 30 lbs K2O as 0-0-60 and 18 lbs N/acre and 20 lbs S/acre as 21-0-0-24. Sprayed 50 lbs N/acre as 32-0-0 on April 14. Applied 28% N on May 29 (See treatments). |
Irrigation: |
Overhead sprinkler irrigation as needed. |
Pest control: |
See Table 69 for herbicide treatments. Sprayed Manzate (3 lbs/acre on July 17 and on August 12), Kocide 2000 (1 lb/acre on July 22), Ridomil (2.5 lbs/acre on July 30), and Rovral (1.5 pt/acre on August 22), for disease control. No insect control needed. |
Harvest: |
Pulled onions on September 17. Onions were allowed to dry in the field, then bagged on Sept 30 and Oct 10 and moved to a shed. The onions were graded October 28 to October 31. |
We tried several new herbicides to determine weed control and onion injury. Callisto, applied either PRE or POST, severely injured onions and eliminated onion yields. Aim severely injured onions when applied at the 1.5 lf stage with a surfactant. When applied at the 2 lf stage without a surfactant it didn’t adequately control weeds, which resulted in lower onion yields. Surpass severely injured onions and the barley cover crop when applied PRE and was similar to Prowl, Dual, Outlook, and Authority when applied at the 2.5 lf stage of onions primarily to give late season weed control. Python, applied PRE, injured the barley cover crop, slightly injured onions, and gave less weed control and lower onion yields. Valor severely injured onions and slightly injured the barley cover crop when applied PRE. When applied at the 2 lf stage it didn’t injure onions, but onion stand and yield were slightly reduced. Nortron, applied PRE, severely injured the barley cover crop, slightly injured onions, and reduced yield due mostly to poor nightshade control. Buctril applied just before onions emerged gave excellent weed control, no onion injury, and high yields. Buctril plus Goal applied at half the standard rate at the 1 lf stage did not result in less onion injury, better weed control, or more yield as compared to the standard rate applied at the 2 leaf stage. The best treatment for onion weed control is Prowl PRE or just after onion emergence, plus Buctril just before onion emergence, plus Buctril + Goal at the 2 lf stage, plus Prowl, Authority, or Dual at the 3 lf stage, plus a final application of Buctril + Goal at the 5 lf stage. Some years the final Buctril + Goal application can be eliminated without loss of yield.
In a comparison of 28% N versus urea, it was found that 28% N applied as an undiluted spray at the 1 lf stage of onions gave higher yields than urea broadcast at the same time. The 28% N helped control some small nightshade and lambsquarters but not pigweed.
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Table 68. Treatment application data at the Oakes Irrigation Research Site, 2003 onion weed control study.
Application timing |
Date |
Time |
Barley height |
Onion height |
Onion growth stage |
Weed height |
Weed growth stage |
PRE1 |
April 24 |
11:00 am |
0 |
0 |
0 |
0 |
0 |
PRE2 |
May 2 |
9:20 am |
1" |
0 |
0 |
<¼” |
cot. |
POST1 |
May 13 |
9:00 am |
3" |
½ to 1 " |
loop |
¼ to ½" |
cot. |
POST2 |
May 29 |
11:40 am |
7" |
3" |
1 true lf |
<1" |
cot. to 2 lf |
POST3 |
May 31 |
11:30 am |
8" |
3" |
1.3 true lf |
¼ to 1" |
cot to 2 lf |
POST4 |
June 3 |
12:00 pm |
8" |
3" |
1.5 true lf |
¼ to 1" |
cot to 3 lf |
POST5 |
June 9 |
1:00 pm |
8" (dying) |
3 to 7" |
2 to 3 true lf |
¼ to 2" |
cot to 6 lf |
POST6 |
June 13 |
11:40 am |
5" (dying) |
4 to 8" |
2.5 true lf |
2" |
mostly dead |
POST7 |
June 30 |
5:10 pm |
--- |
12" |
5 to 6 lf |
1 to 6" |
4 to 12 lf |
All treatments except POST2 and POST4 were applied with a CO2 backpack sprayer using AI 110-04 flat fan nozzles, 45 gpa, and 57 psi. POST2 was applied with a backpack sprayer using 8002 flat fan nozzles, 15 to 25 gpa, and 36 psi. POST3 which was applied with a tractor mounted sprayer, 8004 flat fan nozzles, 37 gpa, and 30 psi).
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Table 69. Onion weed control treatments at the Oakes Irrigation Research Site, 2003.
Treatment number |
Herbicides |
Rates |
Application timing1 |
1 |
Prowl; Buctril + Goal |
1.5 pt; 1.5 + 0.5 pt; 1.5 pt |
POST1 & 6; POST5 & 7; POST6 |
2 |
Dacthal; Buctril + Goal; Prowl |
8 lbs; 1.5 + 0.5 pt; 1.5 pt |
PRE2; POST5 & 7; POST6 |
3 |
Valor; Buctril + Goal |
3.0 oz;1.5 + 0.5pt |
PRE; POST5 & 6 |
4 |
Prowl; Valor |
1.5 pt; 1.5 oz |
PRE; POST5 |
5 |
Nortron; Buctril + Goal |
3 pts; 1.5 + 0.5 pt |
PRE; POST5 |
6 |
Prowl; Buctril + Goal; Buctril + Goal |
1.5 pts; ¾ + ¼ pt; 1.5 + 0.5 pts |
POST1 & 6; POST4; POST7 |
7 |
Prowl; Buctril + Goal; Prowl |
1.5 pts; 1.5 + 0.5 pt; 1.5 pt |
POST1; POST5 & 7; POST6 |
8 |
Buctril; Prowl; Buctril + Goal; Prowl |
1 pt; 1 pt; 1.5 + 0.5 pt; 1.5 pt |
PRE2; POST1;POST5 & 7; POST6 |
9 |
Prowl; Buctril + Goal; Dual II Magnum |
1.5 pt; 1.5 + 0.5 pt; 1 pt |
POST1; POST5 & 7; POST6 |
10 |
Prowl; Buctril + Goal; Outlook |
1.5 pt; 1.5 + 0.5 pt; 1 pt |
POST1; POST5 & 7; POST6 |
11 |
Prowl; Buctril + Goal; Authority |
1.5 pt; 1.5 + 0.5 pt; 2 oz |
POST1; POST5 & 7; POST6 |
12 |
Prowl; Buctril + Goal; Surpass |
1.5 pt; 1.5 + 0.5 pt; 2 pts |
POST1; POST5 & 7; POST6 |
13 |
Prowl; Aim(+ NIS) |
1.5 pt; 1/3 oz |
POST1; POST4 |
14 |
Callisto; Buctril + Goal |
6 oz; 1.5 + 0.5 pt |
PRE; POST5 & 7 |
15 |
Prowl; Callisto; Buctril + Goal |
1.5 pt; 3 oz; 1.5 + 0.5 pt |
POST1; POST4; POST7 |
16 |
Balance Pro; Buctril + Goal |
1 oz; 1.5 + 0.5 pt |
PRE; POST5 & 7 |
17 |
Prowl;Balance Pro; Buctril + Goal |
1.5 pt; 1 oz; 1.5 + 0.5 pt |
POST1; POST4; POST7 |
18 |
Python; Buctril + Goal |
1 oz; 1.5 + 0.5 pt |
PRE; POST5 & 7 |
19 |
Surpass; Buctril + Goal |
2 pt; 1.5 + 0.5 pt |
PRE; POST5 & 7 |
20 |
Prowl; Aim; Buctril + Goal |
1.5 pt; 1/3 oz; 1.5 + 0.5 pt |
POST1; POST5; POST7 |
212 |
Prowl; Urea; Buctril + Goal |
1.5 pt; 60 lbs; 1.5 + 0.5 pt |
POST1 & 6; POST2; POST5 & 7 |
222 |
Prowl; 28% N + Urea; Buctril + Goal |
1.5 pt; 15 gal + 15 lbs; 1.5 + 0.5 pt |
POST1 & 6; POST2; POST5 & 7 |
232 |
Prowl; 28% N; Buctril + Goal |
1.5 pt; 25 gal; 1.5 + 0.5 pt |
POST1 & 6; POST2; POST5 & 7 |
24 |
Handweed check |
|
|
1See Table 68 for description of application timings.
2Except for these treatments, all treatments received 20 gal of 28% N applied POST2.
Poast + Dash (1.5 pt + 1 pt/acre) was applied POST3 to the entire study to kill the barley cover crop which was about 8 inches tall and growing vigorously.
Go to top of onion weed control study
Table 70. Barley cover crop injury, onion injury, and redroot pigweed ratings for the Oakes Irrigation Research Site 2003 onion weed control study.
Treatment number1 |
Barley injury |
Onion injury |
Onion height |
Redroot pigweed ratings |
||||||
May 27 |
May 27 |
July 1 |
Aug 5 |
Sept 3 |
July 1 |
May 27 |
July 1 |
Aug 5 |
Sept 3 |
|
|
-------------------------- 0 to 102 ------------------------- |
inches |
-------------------- 0 to 102 ------------------- |
|||||||
|
||||||||||
1 |
0.0 a |
0.0 a |
0.5 ac |
0.5 a |
0.3 ab |
12.5 abc |
9.8 ab |
10.0 a |
9.8 a |
8.5 a-e |
2 |
0.5 a |
0.0 a |
0.3 ab |
0.3 a |
0.8 ab |
12.3 abc |
9.5 ab |
10.0 a |
9.3 abc |
7.3 c-g |
3 |
2.5 b |
9.8 f |
9.0 f |
8.5 d |
9.0 e |
8.5 g |
10.0 a |
10.0 a |
9.8 a |
8.3 a-f |
4 |
0.0 a |
0.0 a |
0.3 ab |
0.5 a |
1.0 ab |
13.3 a |
9.8 ab |
10.0 a |
9.0 abc |
9.8 a |
5 |
9.0 e |
1.3 c |
1.3 cc |
0.0 a |
1.5 b |
11.0 c-f |
9.3 ab |
10.0 a |
7.0 d |
6.8 efg |
6 |
0.0 a |
0.0 a |
0.3 ab |
0.0 a |
0.5 ab |
12.5 abc |
9.5 ab |
9.8 a |
8.8 abc |
7.8 b-g |
7 |
0.0 a |
0.3 ab |
0.0 a |
0.0 a |
0.0 a |
12.3 abc |
9.8 ab |
10.0 a |
9.3 abc |
8.5 a-e |
8 |
0.0 a |
0.3 ab |
0.0 a |
0.3 a |
1.5 b |
12.0 abc |
10.0 a |
10.0 a |
9.0 abc |
7.0 d-g |
9 |
0.0 a |
0.3 ab |
0.3 ab |
0.0 a |
0.5 ab |
11.5 b-e |
9.0 ab |
10.0 a |
9.3 abc |
8.3 a-f |
10 |
0.0 a |
0.0 a |
0.0 a |
0.0 a |
1.5 b |
11.5 b-e |
10.0 a |
10.0 a |
9.5 ab |
8.5 a-e |
11 |
0.0 a |
0.0 a |
3.5 d |
0.5 a |
0.3 ab |
10.3 def |
10.0 a |
10.0 a |
10.0 a |
9.8 a |
12 |
0.0 a |
0.0 a |
0.0 a |
0.0 a |
0.3 ab |
11.8 a-d |
9.8 ab |
10.0 a |
9.5 ab |
9.0 abc |
13 |
0.0 a |
0.0 a |
0.0 a |
4.0 b |
5.0 c |
10.0 efg |
8.8 b |
7.3 b |
4.8 e |
6.5 fg |
14 |
0.5 a |
9.3 f |
10.0 g |
9.8 e |
9.8 e |
0.0 i |
10.0 a |
9.8 a |
8.0 cd |
7.3 c-g |
15 |
0.0 a |
0.0 a |
10.0 g |
10.0 e |
10.0 e |
0.0 i |
10.0 a |
10.0 a |
8.3 bcd |
6.8 efg |
16 |
0.0 a |
0.8 bc |
1.0 bc |
0.0 a |
1.0 ab |
9.8 fg |
9.8 ab |
10.0 a |
9.0 abc |
7.8 b-g |
17 |
0.0 a |
0.5 ab |
9.0 f |
8.0 d |
7.5 d |
3.3 h |
9.8 ab |
9.8 a |
8.3 bcd |
6.3 g |
18 |
4.8 c |
2.3 d |
1.0 bc |
0.5 a |
1.5 b |
10.3 def |
10.0 a |
10.0 a |
9.3 abc |
7.5 b-g |
19 |
6.8 d |
5.0 e |
7.3 e |
6.0 c |
5.5 c |
9.8 fg |
10.0 a |
9.8 a |
8.8 abc |
6.8 efg |
20 |
0.0 a |
0.0 a |
0.0 a |
0.0 a |
0.8 ab |
12.8 ab |
9.8 ab |
7.3 b |
8.0 cd |
6.5 fg |
21 |
0.0 a |
0.3 ab |
0.0 a |
0.0 a |
0.3 ab |
11.8 a-d |
10.0 a |
10.0 a |
9.5 ab |
9.3 ab |
22 |
0.0 a |
0.0 a |
0.0 a |
0.0 a |
0.5 ab |
12.3 abc |
9.3 ab |
10.0 a |
9.5 ab |
8.5 a-e |
23 |
0.0 a |
0.0 a |
0.0 a |
0.0 a |
0.0 a |
12.3 abc |
9.5 ab |
10.0 a |
10.0 a |
8.8 a-d |
24 |
0.0 a |
0.0 a |
0.0 a |
0.0 a |
0.0 a |
13.0 ab |
7.5 c |
10.0 a |
10.0 a |
9.0 abc |
|
||||||||||
Probability |
<.0001 |
<.0001 |
<.0001 |
<.0001 |
<.0001 |
<.0001 |
0.04 |
<.0001 |
<.0001 |
0.001 |
C.V. (%) |
38 |
38 |
26 |
23 |
37 |
12 |
9 |
3 |
11 |
17 |
1See Table 69 for treatments.
2Ratings: 0 is no effect (no weed control or no crop injury); 10 is complete weed or crop kill.
3Values in the same column followed by the same letter are not significantly different at the 0.05 level.
Go to top of onion weed control study
Table 71. Common lambsquarters and hairy nightshade weed control in the Oakes Irrigation Research Site 2003 onion weed control study.
Treatment number1 |
Common lambsquarters ratings |
Hairy nightshade ratings |
||||||
May 27 |
July 1 |
Aug 5 |
Sept 3 |
May 27 |
July 1 |
Aug 5 |
Sept 3 |
|
|
------------------------------------------ 0 to 102 ------------------------------------------- |
|||||||
|
||||||||
1 |
8.3 |
10.0 |
10.0 |
8.5 |
8.3 |
10.0 |
10.0 |
9.8 |
2 |
9.3 |
10.0 |
10.0 |
9.5 |
8.8 |
10.0 |
10.0 |
9.8 |
3 |
10.0 |
10.0 |
10.0 |
9.5 |
10.0 |
10.0 |
10.0 |
10.0 |
4 |
9.3 |
9.8 |
9.3 |
8.0 |
8.8 |
10.0 |
10.0 |
9.8 |
5 |
8.8 |
10.0 |
9.0 |
7.8 |
6.8 |
10.0 |
10.0 |
9.8 |
6 |
8.8 |
10.0 |
9.8 |
8.5 |
8.5 |
10.0 |
9.8 |
9.5 |
7 |
8.3 |
10.0 |
10.0 |
8.8 |
8.3 |
10.0 |
10.0 |
10.0 |
8 |
9.8 |
10.0 |
10.0 |
8.8 |
8.0 |
10.0 |
10.0 |
9.8 |
9 |
9.0 |
10.0 |
10.0 |
9.3 |
7.8 |
10.0 |
10.0 |
10.0 |
10 |
8.8 |
10.0 |
9.8 |
8.5 |
7.5 |
10.0 |
10.0 |
9.5 |
11 |
8.5 |
10.0 |
10.0 |
10.0 |
8.0 |
10.0 |
10.0 |
9.8 |
12 |
8.8 |
10.0 |
10.0 |
8.8 |
7.5 |
10.0 |
10.0 |
10.0 |
13 |
9.0 |
8.5 |
6.0 |
4.5 |
7.5 |
8.3 |
4.8 |
4.0 |
14 |
8.8 |
9.8 |
9.5 |
7.0 |
9.5 |
10.0 |
10.0 |
10.0 |
15 |
8.8 |
10.0 |
9.3 |
6.8 |
7.0 |
10.0 |
10.0 |
10.0 |
16 |
9.5 |
10.0 |
10.0 |
9.3 |
8.0 |
9.8 |
10.0 |
10.0 |
17 |
8.3 |
9.8 |
9.3 |
7.3 |
8.0 |
10.0 |
10.0 |
10.0 |
18 |
9.5 |
10.0 |
10.0 |
8.8 |
8.5 |
10.0 |
10.0 |
9.8 |
19 |
10.0 |
10.0 |
9.5 |
7.3 |
10.0 |
10.0 |
10.0 |
10.0 |
20 |
8.5 |
8.0 |
10.0 |
8.5 |
8.3 |
8.0 |
9.3 |
9.8 |
21 |
8.8 |
10.0 |
9.8 |
8.5 |
7.8 |
10.0 |
10.0 |
9.5 |
22 |
8.8 |
10.0 |
10.0 |
8.8 |
7.3 |
10.0 |
10.0 |
10.0 |
23 |
9.0 |
10.0 |
10.0 |
8.5 |
8.3 |
10.0 |
10.0 |
10.0 |
24 |
5.5 |
10.0 |
10.0 |
9.8 |
7.8 |
10.0 |
10.0 |
10.0 |
|
||||||||
Probability |
<.0001 |
<.0001 |
<.0001 |
<.0001 |
0.01 |
<.0001 |
<.0001 |
<.0001 |
LSD (0.05) |
1.1 |
0.5 |
0.7 |
1.7 |
1.6 |
0.4 |
0.3 |
1.3 |
C.V. (%) |
9 |
4 |
5 |
14 |
14 |
3 |
3 |
10 |
1See Table 69 for treatments.
2Ratings: 0 is no effect (no weed control or no crop injury); 10 is complete weed or crop kill.
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Table 72. Onion yields and total number of bulbs in the 2003 Oakes Irrigation Research Site onion weed control study.
Treatment number1 |
Onion yields |
Total bulbs |
|||||
>3.5" |
3 to 3.5" |
2.25 to 3" |
<2.25" |
total US #1 |
total yield |
||
|
----------------------------------------- cwt/acre -------------------------------------- |
1000s/A |
|||||
|
|||||||
1 |
27 b-h |
112 ab |
64 bc |
9 def |
204 a-d |
339 a-d |
80 ab |
2 |
22 c-h |
99 ab |
79 bc |
16 a-d |
200 a-d |
301 b-e |
79 ab |
3 |
6 hi |
0 e |
0 d |
0 g |
6 gh |
9 g |
1 d |
4 |
20 d-i |
41 cde |
54 c |
10 def |
115 ef |
239 e |
67 b |
5 |
15 f-i |
79 bc |
115 a |
19 abc |
209 a-d |
285 cde |
80 ab |
6 |
18 e-i |
77 bcd |
80 bc |
7 efg |
175 b-e |
334 a-d |
89 a |
7 |
26 b-h |
96 ab |
91 ab |
9 def |
212 a-d |
356 abc |
87 a |
8 |
18 e-i |
91 abc |
73 bc |
19 ab |
183 b-e |
312 b-e |
87 a |
9 |
43 abc |
115 ab |
79 bc |
7 efg |
238 abc |
340 a-d |
76 ab |
10 |
38 a-e |
89 abc |
62 bc |
19 abc |
189 b-e |
310 b-e |
85 a |
11 |
45 ab |
117 ab |
84 b |
13 a-e |
245 ab |
369 ab |
84 a |
12 |
41 a-d |
90 abc |
77 bc |
12 cde |
208 a-d |
321 a-e |
79 ab |
13 |
0 i |
0 e |
1 d |
6 efg |
1 gh |
11 g |
11 cd |
14 |
0 i |
0 e |
0 d |
0 g |
0 h |
0 g |
0 d |
15 |
0 i |
0 e |
0 d |
0 g |
0 h |
0 g |
0 d |
16 |
28 b-g |
94 ab |
82 bc |
12 b-e |
204 a-d |
307 b-e |
73 ab |
17 |
0 i |
3 e |
2 d |
3 fg |
4 gh |
12 g |
6 cd |
18 |
14 f-i |
80 bc |
82 bc |
20 a |
177 b-e |
269 de |
76 ab |
19 |
36 a-f |
28 de |
12 d |
3 fg |
76 fg |
108 f |
20 c |
20 |
8 ghi |
76 bcd |
71 bc |
12 b-e |
155 de |
289 b-e |
80 ab |
21 |
28 b-g |
85 bc |
63 bc |
9 def |
176 b-e |
297 b-e |
77 ab |
22 |
35 a-f |
107 ab |
72 bc |
14 a-e |
214 a-d |
352 abc |
83 ab |
23 |
55 a |
137 a |
74 bc |
10 def |
266 a |
398 a |
88 a |
24 |
31 b-f |
70 bcd |
66 bc |
8 efg |
167 cde |
343 a-d |
86 a |
|
|||||||
Probability |
<.0001 |
<.0001 |
<.0001 |
<.0001 |
<.0001 |
<.0001 |
<.0001 |
C.V. (%) |
68 |
52 |
37 |
55 |
36 |
24 |
19 |
1See Table 69 for treatments.
2Values in the same column followed by the same letter are not significantly different at the 0.05 level.
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