Golden Chain Tree, Goldenchain Tree 'Fastigiata'

I was on the campus of a beautiful convent in Livonia, MI, yesterday and saw one of these beauties for the first time. My prior experien...Read Morece was limited to drooling over pictures in nursery catalogues. This specimen was growing in a semi-shaded area between two large blue spruces. It was about 10' tall and 10' wide with multiple trunks. There were seed pods from last year still on the tree/shrub and I collected
several. There were multiple seedlings under and close by the parent. The grass was kept mowed all around so these seedlings didn't seem to pose a problem. It was beautiful.

I 've had my weeping golden chain tree for 3 years now and in the past it has come to life in the spring and bloomed..well..this spring i...Read Moret started out with 2 leaves which never got bigger than 2 inches. Those leaves have since dried up and are gone. We haven't had hot weather, so the plant hasn't dried out. I checked and it is still alive.I scratched the bark and it is green.
I have noticed suckers coming up from the base. I dont know if I should cut them back or let them take over but im sure it wont be the weeping version? If anyone has any answers for me on how or what to do to get the tree to grow leaves, please post them here.
Thanks
the weather here has been cool on the most part this spring..we even had some late frost in May...
Im in zone 6a, Connecticut

Goldenchain Tree is never more than 8 feet wide, yet reaches 20 feet tall and blooms very heavily over an extended late spring and early ...Read Moresummer season.

Native to central and southern Europe, this deciduous tree normally tends to be shrubby and a bit rangy, but this fastigiate form points straight up, with tidy branching and a full but compact form. The flowers arise in drooping clusters 12 inches or so long, remaining for many weeks to fill the garden with their color and scent.

Note: all parts of this plant are poisonous. Zones 5-7