Tom welcome. Here is some info I think will help. The 3rd one is a Sonar label which may help but first read the first 2 links for context.

http://aquaplant.tamu.edu/database/submerged_plants/sago_pondweed_mgmt.htm

http://aquaplant.tamu.edu/database/submerged_plants/coontail_mgmt.htm

http://plants.ifas.ufl.edu/guide/sonaras_label.pdf