Conduct a survey after planting but before weeding to determine the spectrum of weeds present. Records from previous crops are also helpful to indicate which weeds may be in the seed bank and require control before germination. Depending on the planting date, it is possible that you will see winter annuals and summer annuals.
How to survey
Walk through each field in a random pattern, rating the degree of infestation for each weed species. Use either a numeric scale of 1 to 5 (1 being the lightest, 5 being the heaviest), or rate as "light," "medium," or "heavy."
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