Showdown (glyphosate), EPA# 71368-20, READ THE LABEL
Showdown contains 4 pounds per gallon of the active ingredient glyphosate, in the form of its isopropylamine salt. Showdown provides post-emergence systemic control of most annual and perennial weeds in bearing and nonbearing vineyards where contact with green grape foliage can be avoided. Glyphosate is primarily absorbed through mature leaves, and it moves systemically through the plant to other plant parts including the roots, and can cause serious injury to grapevines if applied in that manner. Consult the label to determine the proper use rate for specific situations including weed species present, growth stage, and environmental factors. A maximum of 10.6 quarts Showdown, including the equivalent amount of other glyphosate products, can be applied per acre per season. Showdown can be tank mixed with certain pre-emergence herbicides registered for use in grapes when following all product label restrictions; consult the label for a list of permissible tank mix partners. 4 hour reentry interval, 14 days to harvest.
2.5 Gallon