http://www.tsb.gc.ca/eng/enquetes-investigations/aviation/2014/a14p0132/a14p0132.html
It is a turboprop, there is a tandem-seat version which I gather from limited information the Sky Warden design has.
I presume the 11 hour endurance comes from making the fuselage insecticide/fertilizer tank into a fuel tank.
Note antenna on top of right wing in Forbes photo of flight deck.
Could the US’ military version have a QC kit for spraying when locusts multiply, as they did recently? (Locusts/grasshoppers/whatever-name multiply in huge quantities when land is moister than usual thus more vegetation for food, they have to be attacked at a particular time in their growth. A serious food problem in Africa as they eat crops.) Spraying is a common use of ag aircraft, dusting crops another., perhaps fertilizing as well.