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 45. Onion weed control treatments
Table 46. Treatment application data
Table 47. Onion injury, barley cover crop injury, and redroot pigweed ratings
Table 48. Common lambsquarters and hairy nightshade weed ratings
Table 49. Onion yields and total number of bulbs
Tables of pesticides used at the Oakes Irrigation Research Site -- Trade names and common names
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: |
Hecla sandy loam, Embden sandy loam, and Maddock sandy loam; pH=6.6; 2.0% organic matter; soil-P and soil-K were very high; soil-S was low. |
Previous crops: |
2001 - herbs, pepper, and sweetcorn; 2000 - field corn; 1999 - soybean. |
Seedbed preparation: |
Disked on Nov 1, 2001. Multiweeded (field cultivated) on April 23 to incorporate fertilizer and smooth the seedbed. |
Planting: |
Direct seeded Teton onions (174,000 seeds/acre) on April 25 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 on 8 ft centers (giving a 2-ft border between plots). The study had 4 reps. |
Fertilizer: |
On April 18, broadcast 18 lbs N/acre and 20 lbs S/acre as 21-0-0-24. Sprayed 50 lbs N/acre as 28-0-0 on April 23. Applied 28% N on May 31 (See treatments). Side dressed 50 lbs N/acre as urea on June 26. |
Irrigation: |
Irrigated 0.5 inches with hand-move, overhead sprinklers on May 24 and on May 31 to activate herbicides. Irrigated with underground drip irrigation as needed the rest of the season. |
Pest control: |
See Table 45 for herbicide treatments. Sprayed Maneb (2 lbs/acre on July 11 and on Aug 7), Ridomil MZ72 (2.5 lbs/acre on Aug 2), Ronilan (2 lbs/acre on Aug 16), and Dithane F45 (2 qt/acre on Aug 27) for disease control. No insect control needed. |
Harvest: |
Hand harvested on Sept 18 and 19. Bagged on Oct 7 and 8. Graded on Oct 29 and 30. |
Valor injured onion when applied PRE. Nortron injured onion and severely injured the barley cover crop. Valor and Nortron controlled weeds early, but lost control later in the season. Onion yield for these treatments was close to zero because of onion injury and weed competition, except for when Buctril + Goal was added to the Nortron treatment. Buctril + Goal gave good control of pigweed and excellent control of lambsquarters and hairy nightshade. The half rate of Buctril + Goal did not injure onions less and was a little weak on pigweed and nightshade. Spraying 28% N increased redroot pigweed control slightly vs. broadcasting urea. Authority gave good weed control early, but lost control of hairy nightshade later in the season, which eliminated any onion yields. When Buctril + Goal was applied at POST4 and POST6, applying Dual, Outlook, Prowl, or Authority at POST5 did not improve late season weed control.
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Table 45. Onion weed control treatments at the Oakes Irrigation Research Site, 2002.
Treatment number |
Herbicides |
Rates |
Application timing1 |
|
|||
1 |
Prowl; Buctril + Goal |
1.5 pt; 1.5 + 0.5 pt; 1.5 pt |
POST1 & 5; POST4 & 6 |
2 |
Dacthal; Buctril + Goal; Prowl |
8 lbs; 1.5 + 0.5 pt; 1.5 pt |
PRE2; POST4 & 6; POST5 |
3 |
Valor |
1.5 oz |
PRE1 |
4 |
Valor |
3.0 oz |
PRE1 |
5 |
Prowl; Valor |
1.5 pt; 1.5 oz |
PRE1; POST4 |
6 |
Nortron |
3 pts |
PRE1 |
7 |
Nortron |
6 pts |
PRE1 |
8 |
Nortron; Buctril + Goal |
3 pts; 1.5 + 0.5 pt |
PRE1; POST4 & 6 |
9 |
Prowl; Buctril + Goal |
1.5 pts; ¾ + ¼ pt |
POST1 & 5; POST3 & 6 |
10 |
Prowl; Buctril + Goal |
1.5 pts; ¾ + ¼ pt |
POST1 & 5; POST4 & 6 |
11 |
Prowl; Buctril + Goal |
1.5 pt; 1.5 + 0.5 pt |
POST1; POST4 & 6 |
12 |
Buctril; Prowl; Buctril + Goal |
1 pt; 1.5 pt; 1.5 + 0.5 pt |
PRE3; POST1 & 5; POST4 & 6 |
132 |
Prowl; Urea; Buctril + Goal |
1.5 pt; 130 lbs; 1.5 + 0.5 pt |
POST1 & 5; POST2; POST4 & 6 |
142 |
Prowl; 28% N + urea; Buctril + Goal |
1.5 pt; 15 gal + 33 lbs; 1.5 + 0.5 pt |
POST1 & 5; POST2; POST4 & 6 |
152 |
Prowl; 28% N; Buctril + Goal |
1.5 pt; 25 gal; 1.5 + 0.5 pt |
POST1 & 5; POST2; POST4 & 6 |
16 |
Prowl; Buctril + Goal; Dual II Magnum |
1.5 pt; 1.5 + 0.5 pt; 1 pt |
POST1; POST4 & 6; POST5 |
17 |
Prowl; Buctril + Goal; Outlook |
1.5 pt; 1.5 + 0.5 pt; 1 pt |
POST1; POST4 & 6; POST5 |
18 |
Prowl; Buctril + Goal; Authority |
1.5 pt; 1.5 + 0.5 pt; 3 oz |
POST1; POST4 & 6; POST5 |
19 |
Prowl; Authority |
1.5 pt; 3 oz |
POST1; POST5 |
20 |
Prowl; Buctril + Goal; Prowl |
1.5 pt; 1.5 + 0.5 pt; 1.5 pt |
PRE1 & 5; POST4 & 6 |
21 |
Handweed |
|
|
1See Table 46 for description of application timings.
2Except for these treatments, all treatments received 20 gal of 28% N applied POST2.
On May 29, Fusilade + NIS (12 oz/acre + 1 pt/25 gal) was applied to the entire study with a tractor mounted sprayer using AI 110-04 flat fan nozzles, 36 gpa, and 55 psi pressure. This was to kill the barley cover crop which was about 7 inches tall and vigorously growing.
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Table 46. Treatment application data at the Oakes Irrigation Research Site, 2002.
Application timing |
Date |
Time |
Barley height |
Onion height |
Onion growth stage |
Weed height |
Weed growth stage |
|
|||||||
PRE1 |
April 26 |
10:30 am |
0 |
0 |
0 |
0 |
0 |
PRE2 |
May 10 |
10:15 am |
1" |
0 |
0 |
<¼” |
cot. |
PRE3 |
May 13 |
9:45 am |
2" |
0 |
0 |
¼” |
cot. |
POST1 |
May 24 |
9:00 am |
4.5" |
1" |
loop to flag lf |
½ to 1" |
cot. to 2 lf |
POST2 |
May 31 |
10:15 am |
7.5" |
3" |
1 true lf |
1 to 2" |
2 to 4 lf |
POST3 |
June 5 |
10:00 am |
7" (dying) |
4.5" |
1.3 true lf |
1 to 3" |
2 to 5 lf |
POST4 |
June 7 |
2:30 pm |
6" (dying) |
5" |
1.8 true lf |
1 to 5" |
2 to 8 lf |
POST5 |
June 11 |
4:00 pm |
3" (dead) |
6" |
2.5 true lf |
2" |
mostly dead |
POST6 |
June 25 |
3:15 pm |
--- |
8" |
5 true lf |
1 to 6" |
4 to 12 lf |
Treatments applied with a CO2 backpack sprayer using AI 110-04 flat fan nozzles, 45 gpa, and 57 psi (except POST2 was applied using 8002 flat fan nozzles, 15 to 25 gpa, and 36 psi).
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Table 47. Onion injury, barley cover crop injury, and redroot pigweed ratings for the Oakes Irrigation Research Site 2002 weed control study.
Treatment number1 |
Onion injury |
Barley injury |
Redroot pigweed ratings |
|||||
5/31 |
6/18 |
7/5 |
5/31 |
5/31 |
6/18 |
7/5 |
9/11 |
|
|
---------------------------------------------- 0 to 102 ---------------------------------------------- |
|||||||
|
||||||||
1 |
0.0 a3 |
0.0 a |
1.0 abc |
0.0 a |
9.3 a-d |
9.8 ab |
9.5 ab |
8.3 a-d |
2 |
0.0 a |
0.5 a |
1.0 abc |
0.0 a |
8.8 b-e |
9.5 abc |
9.0 abc |
7.0 de |
3 |
2.3 cd |
0.3 a |
3.8 e |
0.0 a |
8.5 cde |
6.3 d |
5.0 e |
4.3 fg |
4 |
2.8 d |
0.3 a |
1.8 cd |
0.0 a |
10.0 a |
8.8 c |
7.0 d |
6.8 de |
5 |
0.3 ab |
0.0 a |
0.8 abc |
0.0 a |
8.5 cde |
6.8 d |
4.5 e |
3.5 g |
6 |
4.0 e |
1.3 b |
5.3 f |
7.0 b |
9.5 abc |
9.0 bc |
8.0 cd |
7.3 cde |
7 |
4.3 e |
1.8 b |
3.0 e |
9.0 d |
9.8 ab |
9.0 bc |
8.8 bc |
9.0 abc |
8 |
2.3 cd |
1.3 b |
1.5 bc |
7.5 c |
10.0 a |
10.0 a |
10.0 a |
9.0 abc |
9 |
0.3 ab |
0.0 a |
0.5 ab |
0.0 a |
9.3 a-d |
9.5 abc |
8.8 bc |
6.0 ef |
10 |
0.8 ab |
0.0 a |
0.5 ab |
0.0 a |
9.4 abc |
9.8 ab |
9.3 ab |
7.5 cde |
11 |
1.3 bc |
0.3 a |
0.8 abc |
0.0 a |
9.3 a-d |
10.0 a |
10.0 a |
8.0 bcd |
12 |
0.3 ab |
0.0 a |
1.0 abc |
0.0 a |
8.7 b-e |
9.8 ab |
9.5 ab |
6.6 de |
13 |
0.0 a |
0.3 a |
0.8 abc |
0.0 a |
8.3 de |
9.5 abc |
9.5 ab |
7.5 cde |
14 |
0.3 ab |
0.3 a |
0.3 a |
0.0 a |
9.0 a-e |
9.5 abc |
9.8 ab |
8.0 bcd |
15 |
0.0 a |
0.0 a |
0.5 ab |
0.0 a |
9.5 abc |
9.5 abc |
9.5 ab |
7.5 cde |
16 |
0.3 ab |
0.3 a |
0.8 abc |
0.0 a |
9.3 a-d |
10.0 a |
10.0 a |
8.0 bcd |
17 |
0.0 a |
0.0 a |
1.3 abc |
0.0 a |
8.8 b-e |
10.0 a |
10.0 a |
9.0 abc |
18 |
0.5 ab |
0.3 a |
2.8 de |
0.0 a |
9.0 a-e |
10.0 a |
10.0 a |
9.5 ab |
19 |
0.8 ab |
0.5 a |
3.3 e |
0.0 a |
9.3 a-d |
10.0 a |
9.8 ab |
8.3 a-d |
20 |
0.7 ab |
0.0 a |
0.3 ab |
0.0 a |
8.1 e |
8.8 bc |
9.1 abc |
6.3 def |
21 |
0.0 a |
0.0 a |
0.5 ab |
0.0 a |
8.3 de |
10.0 a |
10.0 a |
10.0 a |
|
||||||||
Probability |
<.0001 |
<.0001 |
<.0001 |
<.0001 |
0.006 |
<.0001 |
<.0001 |
<.0001 |
C.V. (%) |
89 |
145 |
58 |
19 |
8 |
7 |
9 |
18 |
1See Table 45 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 report
Table 48. Common lambsquarters and hairy nightshade weed ratings in the 2002 onion weed control study at the Oakes Irrigation Research Site.
Treatment number1 |
Common lambsquarters ratings |
Hairy nightshade ratings |
||||||
5/31 |
6/18 |
7/5 |
9/11 |
5/31 |
6/18 |
7/5 |
9/11 |
|
|
----------------------------------------------- 0 to 102 ------------------------------------------------ |
|||||||
|
||||||||
1 |
9.3 a-d3 |
10.0 a |
10.0 a |
10.0 a |
8.5 bcd |
10.0 a |
10.0 a |
9.0 ab |
2 |
9.5 abc |
10.0 a |
10.0 a |
10.0 a |
6.0 f |
10.0 a |
10.0 a |
7.8 bc |
3 |
10.0 a |
9.0 c |
8.5 b |
6.3 cd |
9.3 ab |
7.8 de |
5.8 b |
1.3 ef |
4 |
9.8 ab |
9.0 c |
8.0 b |
6.3 cd |
10.0 a |
9.0 bc |
9.3 a |
5.0 d |
5 |
9.6 abc |
9.3 bc |
8.0 b |
7.0 bc |
8.5 bcd |
8.5 cd |
6.8 b |
1.8 e |
6 |
7.8 e |
6.3 d |
6.3 c |
4.5 d |
9.8 a |
6.3 f |
3.8 c |
0.3 ef |
7 |
9.5 abc |
8.5 c |
8.8 b |
8.8 ab |
9.4 ab |
7.0 ef |
4.3 c |
0.0 f |
8 |
9.3 a-d |
10.0 a |
10.0 a |
10.0 a |
9.0 abc |
10.0 a |
10.0 a |
9.3 ab |
9 |
9.0 bcd |
9.8 ab |
9.8 a |
10.0 a |
8.0 cd |
9.8 ab |
10.0 a |
8.5 abc |
10 |
8.8 cd |
9.3 bc |
10.0 a |
9.8 a |
8.3 bcd |
9.8 ab |
9.8 a |
7.0 c |
11 |
9.3 a-d |
10.0 a |
10.0 a |
9.8 a |
8.3 bcd |
10.0 a |
10.0 a |
10.0 a |
12 |
10.0 a |
10.0 a |
10.0 a |
9.6 a |
8.5 bcd |
10.0 a |
10.0 a |
9.5 a |
13 |
9.1 a-d |
10.0 a |
10.0 a |
10.0 a |
8.4 bcd |
10.0 a |
10.0 a |
9.5 a |
14 |
9.3 a-d |
10.0 a |
10.0 a |
10.0 a |
8.3 bcd |
10.0 a |
10.0 a |
9.8 a |
15 |
8.8 cd |
10.0 a |
10.0 a |
10.0 a |
8.0 cd |
10.0 a |
10.0 a |
10.0 a |
16 |
9.3 a-d |
9.8 ab |
10.0 a |
10.0 a |
7.5 de |
10.0 a |
10.0 a |
10.0 a |
17 |
9.3 a-d |
10.0 a |
10.0 a |
10.0 a |
8.0 cd |
10.0 a |
10.0 a |
9.5 a |
18 |
9.5 abc |
10.0 a |
10.0 a |
10.0 a |
7.5 de |
10.0 a |
10.0 a |
10.0 a |
19 |
9.5 abc |
9.3 bc |
9.8 a |
9.8 a |
8.0 cd |
9.3 abc |
6.0 b |
0.0 f |
20 |
9.8 ab |
9.9 ab |
9.9 a |
9.9 a |
7.4 de |
9.7 ab |
10.0 a |
8.3 abc |
21 |
8.5 de |
10.0 a |
10.0 a |
10.0 a |
6.5 ef |
10.0 a |
10.0 a |
10.0 a |
|
||||||||
Probability |
0.006 |
<.0001 |
<.0001 |
<.0001 |
<.0001 |
<.0001 |
<.0001 |
<.0001 |
C.V. (%) |
7 |
6 |
6 |
14 |
10 |
6 |
10 |
18 |
1See Table 45 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 report
Table 49. Onion yields and total number of bulbs in 2002 weed control study at the Oakes Irrigation Research Site.
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 |
25 b-e2 |
108 abc |
76 de |
11 ab |
209 abc |
269 abc |
63 ab |
2 |
16 b-f |
72 c |
85 cde |
12 ab |
174 c |
231 c |
58 b |
3 |
0 f |
0 d |
0 f |
0 c |
0 d |
0 d |
0 c |
4 |
0 f |
0 d |
12 f |
12 ab |
12 d |
28 d |
17 c |
5 |
0 f |
0 d |
0 f |
0 c |
0 d |
0 d |
0 c |
6 |
0 f |
0 d |
0 f |
0 c |
0 d |
0 d |
0 c |
7 |
0 f |
0 d |
0 f |
0 c |
0 d |
0 d |
0 c |
8 |
36 abc |
129 ab |
59 e |
7 bc |
224 abc |
273 abc |
61 ab |
9 |
16 b-f |
104 abc |
92 b-e |
13 ab |
212 abc |
268 abc |
68 ab |
10 |
13 c-f |
80 c |
97 a-e |
13 ab |
190 bc |
246 bc |
65 ab |
11 |
45 a |
129 ab |
91 b-e |
7 bc |
265 a |
320 a |
69 ab |
12 |
18 b-f |
72 c |
86 cde |
16 ab |
176 c |
226 c |
60 b |
13 |
15 b-f |
92 bc |
119 abc |
17 ab |
226 abc |
275 abc |
75 ab |
14 |
10 ef |
103 abc |
127 ab |
11 ab |
240 ab |
290 abc |
75 ab |
15 |
17 b-f |
104 abc |
106 a-d |
18 a |
226 abc |
279 abc |
73 ab |
16 |
23 b-e |
132 a |
86 cde |
10 abc |
242 ab |
288 abc |
68 ab |
17 |
14 def |
134 a |
83 cde |
10 abc |
231 abc |
276 abc |
64 ab |
18 |
34 a-d |
102 abc |
74 de |
10 abc |
210 abc |
285 abc |
65 ab |
19 |
0 f |
0 d |
0 f |
0 c |
0 d |
0 d |
0 c |
20 |
14 b-f |
101 abc |
133 a |
16 ab |
248 ab |
306 ab |
82 a |
21 |
36 ab |
107 abc |
101 a-e |
13 ab |
244 ab |
294 abc |
71 ab |
|
|||||||
Probability |
0.0001 |
<.0001 |
<.0001 |
0.0013 |
<.0001 |
<.0001 |
<.0001 |
C.V. (%) |
95 |
36 |
40 |
76 |
28 |
24 |
27 |
1See Table 45 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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