I may be having success eradicating foxtail thru intensive rotation of pigs, sheep, and diversified poultry. I mowed the areas affected with foxtail early in the season (spring) in effort to make it more palatable to the livestock. In general livestock don't like it much but will eat it when left in the paddock and that is all that is left to forage on. I have seen them eat the seed heads. Foxtail is one of the earliest and longest persisting seed producers of all pasture grasses and weeds. Mowing it can worsen the situation thru seed dispersal. I let the livestock take the foxtail and grasses down to earth (not my usual practice for rotational grazing), and I brought the animals back into the affected areas a few times during this growing season after the foxtail returned (from seed or root mass), to maximize impact and decrease the foxtail seedbank. Now that is Fall and rain approaches, I will broadcast diversified seed into the pasture, especially the barren areas, including clovers, vetch, radishes, turnips, brassicas, etc. After seeding the animals will need to be kept off the area for a couple of months. Spring will tell how well this has worked, but by the looks of it, we are headed in the direction of eradication. Of all the livestock, I believe the pigs had the greatest impact on foxtail. They need to be brought back onto it several times to beat it down, shrink root mass, and impact the noxious seed bank. Pigs will bare the earth, but it is not really a till in the sense that they are not really disturbing soil architecture, instead they turn a thin top layer and get at the root mass. They sure are happy to move onto greener pasture at the end of the foxtail rotation. Its the most voracious I've ever seen the pigs eat grass, after moving the hotwire and moving them over and out of the foxtail paddock.
Foxtail is a truly noxious weed and potentially dangerous to livestock and other animals (but I would take foxtail anyday over herbicides). Foxtail nearly killed one of my valuable livestock guardian dogs. If you ever have an animal with discharge from an orifice and you have foxtail on your property, think of septic foreign body caused by the foxtail seed head. In my dogs case, they were in her nose. This is usually only an issue for animals in spring and summer.
Haying and removing the plant from the land, as someone had mentioned, I can say with certainty does not work. We have been haying for the past three years and the foxtails have intensified in this time period. Keep in mind after you hay, the foxtail will continue to grow and set seed throughout the growing season. Haying also disperses foxtail seed. Not to mention, nobody wants foxtail in their hay.
Also, I've been told in our region of southern oregon that roundup is not effective against most foxtail here