Hello, all. I'm new to this forum and am hoping to get some sound advice about a possible concern regarding my newly planted trees. This past week I purchased seven fastigiate columnar trees called liquidambar "slender silhouette." I seem to be getting conflicting details about their overall growth habits. But they appear to grow anywhere from only 3ft wide to as much as 6-8ft wide but can grow as tall as 40ft tall or more. After doing a ton of research on trying to create a sort of living wall for privacy that doesn't take too much space I decided on this deciduous tree. I planted them 8ft apart and at the edge of our retaining wall. They're about 12" from the edge.
My concern is that on two of the trees the central header branch is now bend and needs to be cut off. They were all approximately 8.5ft tall but the ones that broke at the top lost about 14". Since these trees are columnar and need to rely on a central header branch will this negatively affect their health and overall shape? Here's the thing, when I found these trees at a local nursery I saw them growing in pots under a very large tree. In other words they were growing in shade. I saw that the tops were not straight. The central headers were growing sideways with a very strong curve. They were not facing straight up. I wondered if they were "etiolating" since they were in complete shade as these trees require full sun. Once I got them home I began planting them in their permanent spot in full sun. I'm no tree expert but I am pretty savvy with most plants. And my guess is etiolated tops combined with transplant shock and also receiving a lot of sun they normally weren't used to led the tops to become so weakened that they literally just bent and snapped. I'm including photos for clarity.
Due to losing their header branch will their shape be destroyed and will they be more susceptible to disease and structural problems? I haven't even had them for a full seven days and am wondering if I should insist on returning the damaged ones or can they be saved and grow well?
Hoping to get some sound advice, thanks.
Adrien