I enjoyed a pleasant time on the day of the Fun Fly.  However there were some deer fly visitors that seemed to be annoying.  Today I was visiting another field and the deer fly population was plain and simply vicious.  On my return I did some on-line research.  It turns out that blue is the color most attractive to deer flies.  There are other interesting ways to combat them.  At the field, deer fly traps would put a big dent in the population.  They are pretty cheap to make.

Below are several links and some back story.
The 2nd and 3rd could be applied at the field.

http://www.rci.rutgers.edu/~insects/greenheads.htm
http://deerflytrapumbrella.blogspot.ca/
http://www.instructables.com/id/Deer-Fly-Traps/?ALLSTEPS
http://www.leevalley.com/en/garden/page.aspx?p=10293&cat=2,51555,10293

Russ Mizell, an entomologist with the University of Florida's Institute of Food and Agricultural Sciences, counts the number of deer flies captured on a simple control device he invented (Monday--August 12, 2002). After numerous experiments aimed at controlling the pesky insects, Mizell said the trap that attracted the most deer flies is a 6-inch flower pot painted bright blue and covered with a sticky spray. The trap, which captured as many as 30 deer flies in a one-minute test, is most effective when it's suspended three to six feet above ground and "trolled" or moved no faster than 10 feet per second. (University of Florida photo by Tara Piasio)

Continued next post

Possibly those who mow the grass could use this technique to good effect.

GAINESVILLE, Fla. (Aug. 13, 2002) --- The deer flies are so bad at Dick Coski's farm near Lake Erie in northeast Ohio that he used to get covered in bites mowing his small field.

Hunting for a solution, the retired Social Security claims representative found a Web site about a curious deer fly-control device invented by a University of Florida scientist. The bright blue plastic flowerpot, covered with sticky material and suspended upside-down on a pole, was said to entice and capture the pesky bugs.

It looked goofy. But when Coski, 70, rigged up a similar device and stuck it on the front of his John Deere, he was amazed at the result.

"The deer flies didn't even look at me -- they were all buzzing around that darn flowerpot," Coski said. "My sister-in-law's husband is one of those hard-nosed Englishmen, and he didn't believe me. He came up from Columbus and took a ride on my lawn tractor, and he couldn't get over it."

A flying friend cheekily suggested that to avoid being bitten by deer flies on Sunday, he went to church.  He said he was not bitten, or pestered, by a single deer fly while at church.

YMMV

LOL

a 20 ga. shot gun, loaded with blue "dust" shot is also effective.."buck" shot is no good, it's only effective against the deer itself.   ::)

Perhaps we should try this remedy.  Good for deer flies?

https://m.facebook.com/DolphinFans?_rdr#!/photo.php?fbid=1378920199006108&id=100006644222580&set=a.1376540379244090.1073741827.100006644222580&source=48&ref=bookmark

Bizarre, but worth a try. Now if we only still had shiny new pennies.

I was thinking silver dollars would draw everything in.  LOL