Glufosinate needs to be applied to Palmer amaranth plants less than 4inches in height. If Palmer amaranth is treated at a taller height, some control will be realized but the Palmer amaranth plants will produce seeds resulting in more weeds to control the following growing season and may be able to survive a labelled rateof glufosinate. However, if additionalresidual-activeherbicides are tank-mixed with glufosinate, control failures and escapes may be mitigated.