Turf - Should You Clean or Sanitize Mowers Between Properties?

Anything that slows down the ability of a lawn care company to get from one property to another will result in reduced profits. One question that gets asked is should mowers be cleaned, washed, or sanitized between properties? The following is some information.

From time to time, the question comes up as to whether mowing equipment can transport microorganisms that cause disease (called pathogens). The answer is, "Yes, it certainly can". Inoculum is any pathogen structure that can initiate disease. Microscopic fungal spores are the most common form of inoculum in turfgrass ecosystems. Another important form of inoculum is bits of diseased grass that are cut off by the mower blade.

So if you think for a moment and imagine a microscopic fungal spore, it is easy to imagine that it can attach temporarily to the mower blade, the wheels, the carriage of the mower, etc. Furthermore, anyone who mows grass also knows that fragments of cut leaves also attach to mowers. If these cut fragments are diseased, the disease-causing agent will also be readily transported. So yes, mowers clearly can move fungal inoculum from one property to another.
Does it matter? Well, that is the key question, and the answer, at least for Delaware conditions, is "No". Most of the diseases of significance in Delaware turfgrasses are caused by fungi that are easily transported as windblown spores or are common residents of our soils. Movement of inoculum of on lawn-maintenance equipment doesn't really move inoculum any more effectively that Mother Nature already has.

In my assessment, there seems to be no reason to sanitize lawn maintenance equipment when going from one property to the next. Lawn care operators can breathe a sigh of relief, because if sanitation were biologically important to do so, I can imagine it would be very difficult to implement an effective and economical program for sanitation of mowing equipment in a commercial lawn care operation.

There can be a case made with the transport of weed seeds. If you are in the lawn maintenance business, you do not want to transport problem weeds from one site to another. Having an air tank on the truck to blow off the tops of mower decks and do quick removal of materials stuck to the the underside of mower decks can go a long way toward reducing spread of weeds. If properties are relatively weed free, this will not be necessary.

Information from "DO MOWERS SPREAD DISEASE-CAUSING AGENTS FROM ONE LAWN TO ANOTHER?" By Paul Vincelli in the May 12, 2008 edition of the Kentucky Pest News from the University of Kentucky, College of Agriculture. Comments on weeds by Gordon Johnson, Extension Agriculture Agent, UD, Kent County.