Hi Keith,

The first thing to do is check with the city to see if other buyers of these trees have reported problems. This issue could be linked to weather or storage issues before you picked up your trees. Ask if the city has any kind of guarantee on these trees.

But it could be that your trees are just slow to get established, as ironwoods are. See this page:

https://trees.umn.edu/ironwood-ostrya-virginiana

Make sure the trees are planted at the proper depth. Even with a small tree you should be able to see the trunk widen slightly at ground level. Planting too deep can end in tree death.

Your trees may be slow but fertilizing a stressed tree only stresses them more. Watering regularly is the most important thing to do this year. Water right up until the ground freezes and mulch under the trees to protect the young roots over winter. See this page: 

https://extension.umn.edu/planting-and-growing-guides/watering-newly-planted-trees-and-shrubs

Be sure to protect the trunks over winter with plastic tree guards. That will prevent voles and other rodents from dining on tender young bark. Remove the guards in April and put them back on in November.

I hope this helps. Thanks.