Is there a safe(ish) alternative to RoundUp aside from digging out weeds? Asking because I have a tremendous amount of Henbane [1] I need to get rid of. Deer

Is there a safe(ish) alternative to RoundUp aside from digging out weeds? Asking because I have a tremendous amount of Henbane [1] I need to get rid of. Deer and horses know not to eat it but it's a risk nonetheless. [1] - https://en.wikipedia.org/wiki/Hyoscyamus_niger https://en.wikipedia.org/wiki/Hyoscyamus_niger