Every year is a unique year for our federally endangered annual forb: Clarkia franciscana. Although there has been much research on this plant over the years, each year seems to always bring new surprises.
This year the annual grasses germinated with warm, early rains of October. This was notable since those guilds tend to germinate earlier, with less water and grow quickly, racing to finish their life cycle. Clarkia although germinating within a few weeks of the non-native grasses, tends to grow more slowly, waiting for late spring in order to flower.
We conducted spring surveys of the goat and sheep grazed areas of fall 2016. All of these areas qualitatively had higher counts of native annual forbs per area unit. The lowest section, near the bottom of the hill had prolific blooms of late season tarplants as well as annual forbs. Our late season grazing prescription seems to be highly beneficial for our target forbs in this system. The transect to the right shows area G3, a grazed area where we noted especially beneficial results allowing for higher native cover the following year after the graze.
While annual forbs responded favorably to last years stewardship actions, Presidio Clarkia numbers in the macroplot were lower than in the previous 4 years. This type of annual variability in annual populations has been well documented. We believe this year was simply too wet for too long, benefiting plants with other growth strategies which produce more biomass and grow more quickly. Late season flowering forbs were reduced this year, except in areas which were grazed.
We will continue to monitor the Presidio Clarkia, allowing us to better understand how to retain restore and preserve habitat for this plant.