I asked the person who has these, but she hasn't replied. It is certainly classic suckering behaviour of ash that were cut down.

Considering the current state of Ash in Ottawa, they are probably stump sprouts.

I am sure this is ash foliage

Ash. After the EAB swept thru this area, there are zillions of seedlings and trunk sprouts, tho pretty much no living mature trees.

Thats critically endangered North American Ash! And looks like American White Ash to boot. Lives 600 years but needs to reach age 20 before producing its own seed. Here is link to my EAB Ash tree Science blog you might find interesting if willing to conserve your volunteer orphan tree in photo. https://scottieashseed.wordpress.com/