Elusive Rare Plant Shows Itself this Year at the Illa M. Collin Conservation Preserve
Dwarf Ahart’s Rush (Juncus leiospermus var. ahartii)
It was an exciting day when a CNLM biologist spotted the showy stigmas of this minuscule plant growing in what is known to be its preferred habitat: bare ground created by gopher mounds along vernal pools and swales. Dwarf Ahart’s Rush (Juncus leiospermus var. ahartii) is known to occur along one of the vernal swales at this Sacramento County Preserve and had been observed regularly, but not by biologists in recent years. Thatch built up around the pool and it was thought that the necessary habitat may not be present to support this plant anymore. “We can’t be sure why the plant came out this year” commented Cathy Little, the CNLM biologist who first observed the plants. “The consistency and amount of precipitation that occurred in Northern California this year was significant.” A Superbloom that California is experiencing this year can bring out species that haven’t been seen in recent times. In addition, this area was included in a prescribed burn last year, coordinated by CNLM and conducted by Sacramento Metro Fire. “The ability to use prescribed fire as a management tool in reducing dense thatch in vernal pool habitat is essential and we are encouraged to see such positive results from these efforts” commented Erik Gantenbein, CNLM Preserve Manager. “This is the first year in a while that water actually flowed through that swale to any degree. It might have helped sweep out the thatch and it also fully inundated the marginal fringe that the plants like” commented Carol Witham a Regional Biologist. Dwarf Ahart’s rush is a California Native Plant Society 1B listed species, meaning they are rare throughout their range. It occurs in Butte, Calaveras, Placer, Sacramento, Yuba, and Tehama Counties, but is known from only nine locations. “Only a few plants have been seen so far this year, but we are keeping our eye out throughout the season as the pool dries” stated Cathy. To read more about CNLM management of this Preserve, visit the CNLM Website. For more information about the Preserve, visit the County Website .