David M. Kopec, Extension Turfgrass Specialist
For years now, Fenarimol has been available as a fungicide and pre-emergence herbicide for Poaannua applied prior to overseeding. The product you have used in the past was RUBIGAN. The same active ingredient is now available in a granular formulation from Riverdale Chemical Company, called "Patchwork." The concentration is 0.78% fenarimol and 99.22% inert ingredients. The active ingredient is 0.0078 lbs. per pound of product material. Previously, "Rubigan" was available as a wettable powder (WP), or soluble liquid (S).
"Patchwork" is labeled for control of necrotic ring spot, summer patch, fusarium blight, take all patch (cool season grass diseases) and spring dead spot of bermudagrass. The product is also labeled (as was Rubigan) for overseeded greens for prevention of Poa annua germination.
Two treatment programs are available, which include either two or three applications to reach the 12 lbs./product/1000 ft2 treatment total for Poa prevention.
Program -A- includes two (2) applications at 6 lbs./1000 ft2, fourteen days apart.
Program -B- includes three (3) applications at 4 lbs./1000 ft2, fourteen days apart.
For perennial ryegrass overseeding, the second (final) application should be made two weeks before the overseeding date.
If Poa trivialis and/or creeping bentgrass are to be used, use program -B- (3 applications at 4 lbs./1000 ft2). Make sure that the last application of "Patchwork" is made thirty days before overseeding.
"Patchwork" is available in 30 lb. bags from Riverdale Chemical Company of Glenwood Illinois. For more product information, call 1-800-345-3330.
Issued in furtherance of Cooperative Extension work, acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture, James A. Christenson, Director, Cooperative Extension, College of Agriculture & Life Sciences, The University of Arizona. The University of Arizona is an equal opportunity, affirmative action institution. The University does not discriminate on the basis of race, color, religion, sex, national origin, age, disability, veteran status, or sexual orientation in its programs and activities.