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AgAlerts 2009 From Griggs County
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Issue #5, May 28, 2009
Dandelion was selected as the "Weed Of The Year" in the 2009 NDSU Weed Control Guide. Dandelion is a simple perennial weed that is most associated with undisturbed sites such as lawns hay fields and continuous no-till fields. The bright yellow flowers in the spring and the white seed pappus that blow in the wind are common sights in the spring of the year. What makes this weed a problem is the time of the year we try to control it. Since dandelion is a perennial, the most effective control is in the fall. But most control measures are applied in the spring. Spring control measures have a narrow window and should be applied at the time of blossom. Where as, fall applications can be applied from late August until freeze up. The adaptation of more Roundup ready crops and minimum tillage practices has been beneficial for dandelion becoming a problem weed. On page 134 of the NDSU Weed Control Guide, rates the following herbicides effectiveness for control of dandelion. Note that some of the most effective herbicides are registered for small grains and corn. Since dandelion is a broadleaf, control in broadleaf crops are less effective. Also note the rates of glyphosate that is needed for control in spring applications. To summarize, control dandelion in the fall if it becomes a problem or use a grass crop/broadleaf crop rotation.
| Dandelion Control Rated at Planting in Spring | ||
| Timing | Glyphosate 0.75 lb ae/A |
2,4-D ester 1 lb ae/A |
| Percent Control | ||
| Early Fall | 78 | 60 |
| Late Fall | 82 | 58 |
| Early Spring | 65 | 35 |
| Late Spring | 58 | 30 |
| Post Herbicide Applications for Dandelion Control | ||
| Herbicide | Rate | Control |
| Glyphosate + NIS +AMS (Fall-Applied) | 0.75 lb ae/A + 0.25% + 8.5 lb/100 gal | F-G |
| Glyphosate + NIS +AMS (Spring-Applied) | 0.75 lb ae/A + 0.25% + 8.5 lb/100 gal | P-F |
| Glyphosate + NIS +AMS (Spring-Applied) | 1.5 to 2.25 lb ae/A + 0.25% + 8.5 lb/100 gal | G |
| Glyphosate + 2,4-D ester + AMS (Fall-Applied) | 0.75 lb ae/A + 1 pt/A + 8.5 lb/100 gal | G |
| Glyphosate + 2,4-D ester + AMS (Spring-Applied) | 1.5 lb ae/A + 1 pt/A + 8.5 lb/100 gal | G |
| Glyphosate + 2,4-D ester + Valor +AMS | 0.75 lb ae/A + 2 to 3 oz/A | P-F (Established plants) |
| Glyphosate + 2,4-D ester + Valor +AMS | 0.75 lb ae/A + 2 to 3 oz/A | G (Seedling plants) |
| 2,4-D | 1qt/A | P-F |
| 2,4-D + dicamba | 1qt/A + 0.5 pt/A | G |
| 2,4-D + tribenuron | 1qt/A + 0.3oz/A | F |
| Curtail | 2 to 4 pt/A | G-E |
| WideMatch | 1to 1.33 pt/A | G-E |
| Distinct + NIS + UAN | 6 oz/A + 0.25% + 2.5 % | G |
| Status + PO + UAN | 5 oz/A + 1 pt/A + 2.5 % | G |
Tables are from the 2009 NDSU Weed Control Guide, page 134. For more information go to the following links. 2009 NDSU Weed Control Guide. Or 2008 NDSU Crop Pest Report.
The NDSU Carrington Research Extension Center will be
conducting their annual Crop Management Field School on Thursday, June 25,
2009, at the Carrington R/E Center located 3.5 miles north of Carrington on
Hwy 281. This school is targeted toward crop advisers and producers who
are interested in hands on training in crop, pest and soil management.
Topics for this year's school include the following:
| Morning Sessions (General Session at 9:00 am) | |
| Weed Management Sessions (9:15 am - 12:15 pm) | Topics |
| Weed Identification | Identify more than 60 living weed exhibits and review biology and control |
| Herbicide Mode-of-action | Identify herbicide classes by examining crop and weed injury symptoms. |
| 12:15 pm Lunch at the Center | |
| Pest, Crop and Soil Management Sessions (1:00 pm) | |
| Cereal Disease and Insects | Wheat disease forecasting and fungicide use strategies. |
| Crop and Soil | Update on strategies for use of nitrogen fertilizer. Row crop tillage systems and plant nutrition. |
| Break (2:30 pm) | |
| Afternoon sessions repeated (3:00 pm - 4:30 pm) |
The fee for the school is $50/person before June 22 or $75/person if received after June 22. Applications are available at any County Extension offices or by contacting the Carrington R/E Center at 701-652-2951.
This weed has been increasing due to saline or alkaline conditions caused by high water tables and the increase in reduce tillage systems. Control can be effective when herbicides are applied before the tillering stage but, normally this is not the case. Too often, herbicides are applied when foxtail barley is beyond tillering or starting to head. This is a very difficult stage to have good control. When using glyphosate, lower rates can control small seedlings but high rates are needed to control mature plants. The following data is from Rob Dunn, Alberta Agriculture and Food and Dr. Bob Blackshaw Agriculture and Agri-Food Canada from the publication "Foxtail Barley Control in Direct Seeding Systems" testing other grass herbicides for control of foxtail barley.
In-crop Control for Oilseeds and Pulses
Research by Agriculture and Agri-Food Canada at Lethbridge has shown that
several herbicides registered for grassy weed control in oilseed or pulse crops,
while not registered for foxtail barley control, can provide control or
suppression of foxtail barley seedlings (Table 1).
| Herbicide b |
Foxtail barley growth stage
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3- to 4-leaf stage
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2- to 3-tiller stage
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%control
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% yield increase
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%control
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% yield increase
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| Assure |
99
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79
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97
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53
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| Poast |
85
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71
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66
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40
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| Select |
74
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56
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57
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33
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| Fusion |
61
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50
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31
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14
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| Venture |
51
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43
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17
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11
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NDSU is an equal opportunity institution
Please Contact Our Office For Additional Information
E-mail: john.swenson@ndsu.edu
Go to the 2008 AgAlert Index Page