I was going to spray some sweet gum trees in the next 2 weeks in some recently thinned pines on our place but I am unsure on how much chemical to add per gallon. My sprayer is spraying +/-15 gallons an acre. The label is saying 2.5 gallons per every 100 2.5%. Is this sufficient or should I use the 1% solution? I am not sure as I haven't had much experience with this.