Prowl on foxtail?

 Good Morning

 I am looking for some insite and or help with foxtail control on my alf/orchard fields. The last couple of years the foxtail has become a problem in late July/Aug time frame. We have sprayed the last two years at the last week of April first week of May, 3 pints/acre. in June 2018, we had 12" of rain. May 2019, we had 10". After the monsoons, it was followed by a flash drought, 1 1/2 " the next 2 months both years. Seems the weeds love it but not so much the hay. I understand after that much rain, most of the prowl would be gone.

 Do any of you do a split application of prowl? Or should I just do my regular 3pt early and come back again if we think it has been washed away?

 

 Thanks 

Prowl on foxtail?