This is a spider called the spined micrathena, scientific name Micrathena gracilis. Our veterinarian found it tangled up in its own web, as you can see in the photo below.  These spiders spin a web with a diameter of about 10 inches, that is very tightly coiled. It is often found in woody areas, and is harmless to humans.

Generally spiders create a web using two basic types of strand, although there are exceptions to this rule. One type is sticky, and is used for catching prey, and this strand variety is criss-crossed with a normal non-sticking type that the spider can walk on. Spiders are generally very good about identifying the correct strand, and will not generally tangle themselves up, however this little girl simply had the misfortune to be caught in a big gust of wind. It tangled her web up in a ball around her, and caught her with the sticky bits. Fortunately, one of our veterinarians was walking by, and managed to free her from her predicament. Here she is ready to make another nest!