Due to lessons learned from cold spring conditions in 2020, it seems like more growers are trying out early planted soybeans that are more cold tolerant prior to emergence. Planting ranges widely depending on soil conditions in your area, but some areas are making great headway planting soybeans. While getting your crop in the ground is important, it’s also important to keep the fields weed-free to maintain the best potential for yield.
The critical weed-free period is the period of crop development where weed competition can reduce yields dramatically (up to 60% reduction or more). If the crop is kept weed-free during these stages of development, no yield reduction should occur.
For soybeans, the Critical Weed-Free Period lasts from the 1st to 3rd trifoliate stage of development, although keeping the field clean earlier has shown benefits. Weeds emerging after this time won’t affect yield, although control may still be necessary to prevent additions to the weed seed bank, or prevent issues at harvest.
For this reason, it is important to have a herbicide program in place to prevent germinating weeds from emerging and causing yield losses. Using herbicides with residual activity, as well as multiple modes of effective action on target problem weeds, is a sure-fire way to maximize your crop’s potential.
The charts linked here shows some of our most popular herbicide programs for your IP or herbicide tolerant soybean crops. Make sure that your desired program:
- Has effectiveness on the weeds in your individual field
- Has residual activity for targeted weeds, especially weeds that can cause quality issues like Eastern Black Nightshade in IP soybeans
- Uses multiple modes of action for tough to get or resistant weeds like Canada Fleabane
- Rotates chemistry on that particular field
Always refer to pesticide labels and OMAFRA Pub 75 for official ratings, notes, and rates!
Learn more about Sylvite’s Soybean Herbicide Program, here.
We are here to help – get in touch if you have any questions or need any assistance with your crops. Together we can develop a herbicide program to suit you and your crop needs.
*CHOOSE A BURNDOWN PROGRAM + RESIDUAL PROGRAM TO SUIT YOUR NEEDS
BURNDOWN PARTNERS
| PRODUCT | RATE | COST/AC | FLEABANE | STRENGTHS | WEAKNESSES |
| Blackhawk + glyphosate | 0.45L/ac + 1.0L/ac equiv | $16.63 | Emerged (<10cm) | Excellent burndown for fleabane, good broadleaf control. Good kill on perennial weeds, more complete kill. | No residual weed control. Slower burndown than Eragon. |
| Eragon LQ + Merge + glyphosate | 29.5mL/ac + 0.4L/ac + 1.0L/ac equiv | $16.06 | Emerged (20 leaf) | Excellent broadleaf burndown, including glyphosate-resistant fleabane. Fast-acting. | No residual weed control. May burn perennials down too quickly for complete kill. |
| 2,4-D Ester + glyphosate | 0.33L/ac + 1.0L/ac equiv | $10.25 | Emerged | Good burndown for perennials, slow-acting for more complete kill. Less expensive option. | Label states 2,4-D Ester needs to be applied 7 days before planting. Slower burndown than Eragon. No residual. |
| Elevore + glyphosate | 29.5mL/ac + 1.0L/ac equiv | $14.98 | Emerged | Excellent burndown for fleabane and ragweed, including Group 2 resistant biotypes. More complete kill than Eragon. | Must wait 7 days after application to plant. No residual control; add a residual partner such as Sencor. |
| Enlist 1 + glyphosate | 0.73L/ac + 1.0L/ac equiv | $15.12 | Emerged | New low drift/low volatility 2,4-D Choline. Same control as 2,4-D + glyphosate. Apply anytime on Enlist Beans. | ONLY REGISTERED FOR USE ON ENLIST BEANS. No residual. Slower burndown than Eragon. |
| Engenia + glyphosate | 0.25L/ac + 1.0L/ac equiv | $14.70 | Emerged | Excellent control of glyphosate-resistant weeds, perennials. New formulations are less volatile, lower use rates. | ONLY FOR USE ON XTEND BEANS. Specific application requirements, less risk using pre-plant over in-crop. |
RESIDUAL CONTROL PARTNERS
| PRODUCT | RATE | COST/AC | FLEABANE | STRENGTHS | WEAKNESSES |
| Authority Supreme | 162 mL/ac | $21.97 | No | Good control of many common grassy and broadleaf weeds, including foxtails, pigweed, cleavers and lamb’s quarters. | Weaker on ragweed, no fleabane control. Mix with a partner like Sencor or Canopy Pro. Rate depends on soil type. |
| Bifecta | 40ac/Case | $25.75 | Residual | Excellent broadleaf weed control, including nightshade & fleabane. Valtera + Sencor. | Weak residual grass control, weak perennial weed control. Weaker on ragweed as well. Cannot be incorporated. |
| Boundary | 1.0L/ac | $23.90 | Residual | Good grass, nightshade control, suppresses lamb’s quarters. Will control fleabane at this rate. | Can reduce rate to 0.75L/ac to reduce cost, will reduce control, incl fleabane control. Weak on ragweed. |
| Guardian MAX | 15ac/jug | $23.67 | No | Great option for fields with dandelion, sow thistle. Includes glyphosate for burndown ($5.98/ac). | No resistant fleabane control, better in-crop for sow thistle. Limited residual control. |
| Sencor | 220g/ac | $14.26 | Residual | Best residual option for fleabane, good control of ragweed and lamb’s quarters. | Group 2 resistance can reduce control, limited residual grass control. |
| Valtera EZ | 60mL/ac | $18.87 | Residual | Very good lamb’s quarters, nightshade and pigweed control, suppression of fleabane. | DO NOT INCORPORATE. Weak residual grass control, splash-up may cause injury, no yield impact. |
| Zidua SC | 167mL/ac | $37.81 | No | Good control of grasses, nightshade, pigweed and waterhemp. | Cannot be incorporated. Rate needs to be adjusted for soil type. Only a few broadleaf weeds controlled. |
| PRODUCT | RATE | COST/AC | FLEABANE | STRENGTHS | WEAKNESSES |
| Glyphosate | 1L/ac equivalent | $5.83 | No | Simple, inexpensive and broad-spectrum. | Resistance issues, no residual control, may not take out larger perennials on its own. |
| Guardian MAX | 15ac/Jug | $23.67 | No | Good option for perennials, great on sow thistle. Provides some residual control. | Residual control on grasses, ragweed, lamb’s quarters, nightshade is weak, and some possible resistance. Can’t use if Guardian used for burndown. |
| Glyphosate + Engenia | 1L/ac equiv. + 0.25L/ac | $14.70 | Emerged | Controls glyphosate resistant weeds in Xtend soys, good on tough perennials. Broad spectrum. | ONLY REGISTERED FOR USE ON XTEND BEANS. Only use dicamba post if necessary to reduce off-target movement. |
| Enlist 1 + glyphosate | 0.5L/ac + 1.0L/ac equiv | $15.12 | Emerged | New low drift/low volatility 2,4-D Choline. Apply anytime on Enlist Beans. Good option for perennials/tough weeds. | ONLY REGISTERED FOR USE ON ENLIST BEANS. No residual. |
**This is a summary of our most popular herbicide programs. Refer to OMAFRA Publication 75A for all weed control options, ratings and rates.