CALLING ALL DASH/ DESH/ DESCH/ DASCHSKY/ TESH/ TESCH/ TEST DESCENDANTS!
From my research so far, it appears to me that the spelling became whatever whomever was writing it wrote. I see it written all sorts of different ways in the original records so even back in the 1799's they were unsure how to spell it. I even saved a record where it documents this.
Looks like the primary DASH/ DESH/ DESCH/ DASCHSKY/ TESH/ TESCH/ TEST ancestors in America were Methodist, Lutheran (?) Dutch Reform Church members who were Dutch and/or German pioneers who originally arrived in the US through the Port of Philadelphia then spread out settling pretty much all over the surrounding states including NY, NJ, IL, VA, WV etc. I have also seen people with these variations of the name coming from Bavaria, Switzerland, Prussia (part of modern day Germany was at one time part of Prussia) and the Ukraine (Russia at the time)
I think they were mostly women because the name is relatively uncommon is later years; the females married and the name was different through subsequent generations becoming rather uncommon in the 1800's down to the present. On the other hand, the bulk of the records are men because in those days, well, sometimes women were just kind of ignored/not included or counted.
Since it appears that the descendants of this name really have rather little information about their origins or the actual spelling, it might be a good project for WikiTree. I have adopted one Desch orphan profile, Johannes Desch-3 with that in mind. Anyone else interested in collaborating on this?