There are about 700 varieties of Selaginella plants which are often referred to as spike moss or arborvitae ferns. Selaginella plants are very diverse in their size and in the ways they grow.  Many can be found growing wild in tropical America, Asia, China, Japan, North America, Mexico, South Africa and Australia. Selaginella, depending upon the variety, may be a creeping, climbing, or trailing plant. Selaginella kraussiana, which is also called Spreading Club Moss or Trailing Moss, grows about ½ inch high and has a limitless spread. S. kraussiana has very small bright green leaves that overlap on trailing jointed stems. Selanginella martensii is a small bushy plant that grows about 7-9” tall and just as wide. S. martensii has thick, multi-branched stems filled with small green leaves. When S. lepidophylla, a native of desert and semi-desert regions,  doesn’t get enough water, the leaves roll into tight brown balls (a phenomenon known as cespitose) and the plant becomes totally dormant. Once this Selaginella  gets some moisture, the leaves open up, turn green, and the plant starts to grow again. This is why the  Selaginella lepidophyllagets is called the “Resurrection Plant.”