When it comes to making hay the best thing to treat clover with is 2-4D. You will take it out, which is the best thing for it and your hay fields. There is no herbicide that will take out broad leaf weeds and not take out clover. Clover is extremely easy to get going again, just broadcast come seed and you have it. Clover is nasty to horses with all the dust that comes from the little hairs on the stems and leaves, and it takes a lot longer to dry than your orchard and timothy.
Personally I prefer to use the ester 2-4D as it works much better, but there are other options depending on what you are feeding and where the manure goes. Amine is the least effective of the 2-4D's, the ester, or low volatility is far more effective. Both have a 30 day harvest restriction. Forefront and Milestone are EXTREMELY effective. I think a two week harvest restiction, but no grazing restiction. The chemical in these two will pass through your animals in the manure. If manure is spread on bean fields, or alfalfa it will hurt it, and if used in gardens many plants will be hurt and some killed. BUT as a herbicide it is FANTASTIC and effective. With any herbicide the time to spray is a few days after you baled the hay and there is some regrowth. Two weeks after cutting is getting pretty iffy as to how well the herbicide will do. You can also consider Cimmaron plus, but this should really be used in the early spring. Crossbow is ment for woody weeds like poison ivy. Harvest restiction is NEXT SPRING.
Legumes like clover and alfalfa are not really good mixed with grasses. Weed control is not very good. If you want clover, do a field of clover. If you want grass do a grass field. There are products to get grass out of legumes and broad leafs and legumes out of grasses, but not much to keep a legume, grass mix clean. Sencor DF is the only one I will generally use for this, but it has to be applied after fall dormancy sets in, or before dormancy breaks in the spring. I also think it may be a restricted use product besides.
