Pressure washing costs in Raleigh

The red in Raleigh's dirt comes from iron. North Carolina named the Cecil its official state soil in 1997, and the soil's typical location is in Franklin County, part of the Raleigh metro. A Soil Science Society of America booklet on the Cecil says iron oxides through the soil explain its red color. It also says the Cecil is one of several related Piedmont soils people call "Georgia Red Clay," and that it covers more than 1.6 million acres, about 5 percent of the state.

That clay goes wherever water and shoes carry it. A hard rain splashes it up the bottom few inches of the siding. Feet track it across the patio, and it settles into the joints of a brick walkway. When you show a crew the job, walk them along the low edge of the house, too, not only the driveway.

Then comes the yellow season. The state Division of Air Quality runs North Carolina's only state pollen sampler, at its lab on Reedy Creek Road in Raleigh, from late February through mid-November each year. In a March 2016 release, the agency said Raleigh's highest pollen count on record to that point was 3,524 grains per cubic meter, on April 6, 2010.

The same release said pollen in central North Carolina typically peaks in March and April, while the oaks and pines are flowering.