Did you water them?
I agree with Lesley about calling now for suggestions. Several types of trees are still dormant due to the extended cold weather this season.
I would call Surburban, tell them what you have observed. Even if they do not have a replacement now, they may suggest an alternative suggestion for immediate replacements that will grow in your particular soil type. I also suggest, if you can afford for them to plant the replacement, I strongly recommend spending that extra money. When Surburban plants a tree they will use a root starter to give your new tree a good headstart. And you can get the recommended water needs for that particular tree based on the location and soil it will be in. Also remember we had a dry winter and it could be the trees needed moisture and dried out. Good luck.
Replacement trees won't be available till fall.
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