Early weed control with lower efficacy is generally preferable to no control at all or late control with higher efficacy — as long as weeds are present and not frost damaged. See the updated article with more on spraying in tough conditions, including after a frost or on cool days.
Spraying in cool conditions
![](https://www.canolacouncil.org/wp-content/uploads/2020/10/Weedy-field-pre-seed-Nicole-600x282.jpeg)