Table 2: Visible estimates of common ragweed control by lactofen and Palmer amaranth control by atrazine, imazethapyr, and 2,4-D 4 weeks after application at the manufacturer’s suggested weed size and 4 and 8 days after this weed size using spray solutions mixed the day of application or 4 or 8 days prior to applicationa.

Timing of application after optimum weed sizeTiming of solution preparation prior to applicationVisible control
Common ragweedPalmer amaranth
LactofenAtrazineImazethapyr2,4-D

DaysDays%

0097a85a87a92a
4093b79ab85a89a
4495ab87a83ab88a
8097a68b77b77b
8897a68b74b75b

Means within a weed species and herbicide combination followed by the same letter are not different at .
The letters (a, b, c, ab, and bc) following the means in the table are used to differentiate between the numbers in terms of statistical differences. Numbers may be different numerically, but if they have the same letter, they are not statistically different because of variation in the biological system.