When we have a dry period in spring or summer, I get predictable calls about some mysterious pest wreaking havoc on lawns.

When we have a dry period in spring or summer, I get predictable calls about some mysterious pest wreaking havoc on lawns.

However, the dry spots callers describe actually result from an irrigation system’s imperfections, revealed following inadequate rain. During sufficient rainfall, rain masks the irrigation system’s imperfections.

The cause for dry spots may be as simple as a maladjusted spray head, a broken spray head, a plugged nozzle, a tree trunk or tall shrub blocking the water, or grass that has grown over a pop-up spray head.

There may be too few sprinkler heads for adequate coverage, insufficient pressure to operate each zone, an incorrect choice of nozzles or wrongly mixing rotors with spray heads on the same zone.

The homeowner may easily fix some problems, but others require a licensed irrigation contractor’s expertise.

These tests can help confirm whether problem areas result from lack of water versus some mysterious pest.

•Take a soil sample in the root zone. Remove a slice of soil 6-8 inches deep with a shovel. Feel the sample for moisture. Do the same in an adjacent area of the lawn that looks normal, and compare the difference. It should be obvious if there’s a difference in moisture between tested areas.

•Place several empty straight-sided cans, such as tuna cans, in the affected area and several in a normal area of the lawn. Turn on the irrigation system and let it run long enough to collect water in the cans. Compare the water amounts collected in the two areas.

•Occasionally, run your irrigation system and check for obvious maladjusted or broken spray heads.

If these tests do not identify the problem as lack of water, you may have a lawn pest.

But don't guess.

If you're unsure about the diagnosis, contact a reputable lawn care or pest control business or your local UF/IFAS Extension Office.


MASTER GARDENER YARD SALE: 8 a.m. to 12 p.m. June 15, University of Florida/Institute of Food and Agricultural SciencesSanta Rosa CountyExtension Office, 6263 Dogwood Drive, Milton. Free admission. Details: Mary Derrick, 623-3868 or maryd@santarosa.fl.gov. Hearing impaired: 983-5373 (TDD).

BUILDING YOUR FINANCES FOR RETIREMENT WEBINAR: 11:30 a.m. to 12:30 p.m. June 20. Register: http://bit.ly/PlanRetire.

TEACH CHILDREN TO SAVE: through July 31. Youths ages 18 or younger who deposit money into a savings account can win a $50 prize. Details: 683-8431; 689-5850, extension 0; or visit your local financial institution.

Larry Williams is an agent at the Okaloosa County Extension office in Crestview.