My wife and I have two identical Hase Kettwiesel All-Rounds (delta style trikes) we ride on trails in Highland Village and Flower Mound, TX.   We bought them in 2011.   Periodically, we travel up to Lake Ray Roberts to ride on trails up there.  We live in Southern Denton Co.
 
I have always been enamored with the tadpole design and in time, I would like to ride one.   Several months ago, we had John’s Trikes in Lancaster perform a complete tune up on them and familiar with that trike dealer.  I have toyed with getting tadpole with an e-assist as a second trike.  My wife and I are in our early 70’s.
 
On a trail in Highland Village, TX, they have a sign posted with regulations to be followed on the trail including “No Motorized Vehicles”.  I am curious what the general rule might be for e-assist trikes for cities primarily on trails and this might apply to e-assist trikes.
 
Thank you in advance for any information.

I’ve discovered most cities posted the non-motorized areas long before e-assist became an item.  I would suggest you reach out to your local authorities for a clarification.  Just last week I rode alongside a North Richland Hills Police department volunteer on the cotton belt trail as we discussed my non-motorized trike compared to his e-bike.  Never thought to ask him For clarification of the rule.  I do know that in my area they are permitted so long as the motor itself cannot exceed 20mph.  While I don’t ride the trails often but when I do it’s not uncommon to encounter several e-assist bikes and trikes out there.  Recently I had been working at a local bike shop to assist in the COVID boom and it was not uncommon to see e-bikes coming in the door almost daily for some minor repair and they all were riding these trails.