Need help after army worms

Howdy Y'all

 Thanks in advance for any advice. This is my first year to have alfalfa here in central Texas in the Brazos bottom with pivot irrigation.  While we have had a steep learning curve and problems but this one is disheartening. After 20 " if rain after Harvey the field looked great coming out of a very dry August and I was looking forward to a cutting next week. Went out to water and the field looked like a disaster area. Army worms stripped almost every lief. We have sprayed but what now. Should we mow the pathetic stems and let it grow back or leave it alone? Should be able to get another cutting this fall if weather cooperates and no more infestations. Alfalfa is not a regular crop here so local advice is sparse. hopefully y'all can help.

Thanks, Bill

Need help after army worms