The bottle tree is made of plastic and can hold up to 45 bottles at one time. Others are available to hold 90. Because it is made of plastic, it is easy to keep clean and sterile. The base is wide to prevent tipping, and has a lip that prevents water from draining all over the counter. When not in use, the tree can be easily disassembled to take up less space for storage. The top of my tree has a handle that allows you to pick up and move it if you need to, however I have not seen this feature on all of the bottle trees I have looked at. Each of the"branches" has enough space to allow water to drain, and air to circulate inside the bottles. Both 12 and 22 oz bottles can be dried on this tree, and it even worked for wine bottles. Some of bottle trees available have a rotating base, a nice feature when your access to the tree is limited. Because the bottles stack up vertically, the tree and drying bottles take up very little space on the counter.
I have seen some bottle trees designed from wood and wood dowels. While I have no doubt that they would allow the bottles to drain and dry effectively, I would be concerned that the sufrace area of the wood might allow bacteria and other microbes to make a home, and that it may be difficult to sanitize properly. Also, the base may allow for water to run all over the counter, definately something to keep in mind.
I really like my bottle tree, and would definately recommend it to anyone with a lot of bottles to clean. Now that I have one, I would not want to be without one. It certainly speeds up the cleaning, sanitizing, and dry process, and is cleaner and a lot less hassle. The only complaint I have is that my batches call for 48-50 bottles. This leaves a few bottles left to set on the counter until the ones on the tree are dry enough to remove.
Bottle trees range in price from $20 - $30 for a 45 bottle holder, to $36 for a 90 bottle holder.