My wife was told by a golf ambassador to be very careful about reaching into the tall grasses for a golf ball. There have been quite a few brown recluse spider bites reported - and they are bad!
The venom will basically kill the skin (necrosis) around the bite and it will slough off and become very prone to infection if not treated by a doctor. Sometimes skin grafts even have to be used.
However, do not kill spiders around the outside of your house as they eat lots of destructive insects.
I attached a link that tells about the brown recluse spider and their bites. It has pictures of the spider.
Brown Recluse Spider Bite Causes, Symptoms, Treatment - Brown Recluse Bite Causes on eMedicineHealth