These two are growing wild in my front garden.
Now is appropriate, as is Spring.
They are aggressive trees, so they should take no issue with an Autumn planting.
Here is an article to help you care for a Poplar:
https://www.gardeningknowhow.com/ornamental/trees/poplar/growing-poplar-trees.htm
My silver poplar is beautifully filled out on one side while the other half looks to have buds yet has never gone past this stage and now looks dead. Is there anything that anyone can tell me as far as what the cause of this might be?
There are, just, a handful of causes that will make the tree die on one side like this. Here is an article that will explain:
https://www.gardeningknowhow.com/ornamental/trees/tgen/tree-is-dead-on-one-side.htm
My question is I leave in Kentucky and want to plant hybrid shade poplar saplings 2-3 ft bare root. Is it to late in season to do so
Yes. I would wait until Autumn. This article will help:
will this tree grow well in south texas?
The hybrid poplar is cottonless, but it didn't make the recommended tree lists. Here is more:
http://texastreeid.tamu.edu/content/TreeDetails/?id=81
https://aggie-horticulture.tamu.edu/southerngarden/treelist.html
https://aggie-horticulture.tamu.edu/ornamentals/natives/POPULUSDELTOIDESVARDELT.HTM
https://texastreeplanting.tamu.edu/viewalltrees.aspx
Can I send a picture some how? Hard to describe and haven’t been helped by google.
This is, either, fungal or bacterial. Fungicides may help, but you will want to keep an eye on soil moisture, as well.
Here are some articles that will help:
https://www.gardeningknowhow.com/garden-how-to/info/using-fungicides-in-garden.htm
https://www.gardeningknowhow.com/special/organic/biofungicide-information.htm
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/testing-moisture-in-plants.htm
Bought some 4-5 foot hybrid poplars. After planting them it appears a few of them have a slight curve to their slender trunk. Is this normal? Should I stake the trees until the get bigger?
Curves are not normal and it is usually caused by a tree searching for the light. Staking is not usually necessary unless you live in a very windy area.
Here's some info about poplars that may help:
https://www.gardeningknowhow.com/ornamental/trees/poplar/growing-poplar-trees.htm