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MEETING REPORT: Mark Berninger, Natural Resource Manager for SD Parks & Recreation Open Space Div.


Mark Berninger, Natural Resource Manager for San Diego Parks and Recreation Open Space Division. Photo credit; Janet Ward.


By Lynn Langley.


Mark Berninger, Natural Resource Manager for San Diego Parks and Recreation Open Space Division spoke on Monday night. He, along with three biologists, are responsible for monitoring and protecting endangered plants and areas over 28,000 acres. They also monitor 22,000 acres of agricultural preserves. He specifically runs a county wide Multi Species Conservation Program and the Vernal Pool Habitat Conservation program.


The Rare plant monitoring program began about 20 years ago. There are over 2,000 species of plants in San Diego County - more diversity than any other county. Mark monitors spots all over the county with different biomes, ecosystems and plants. Ninety-nine percent of plants are monitored when they are in flower because they are easier to observe. His senior biologist has a binder with all of their plant information organized by bloom time. This makes it easy for them to know which plants to look for at any time of year. They work with many different government entities. All the contributing organizations use the protocol developed by Mark and his group at Parks and Rec. This makes it easy for data to be shared. To better understand how the plants are faring, they are scheduled to begin genetic mapping in the near future. They are constantly fighting battles with how to deal with invasive species without damaging the rare plant species.


Photo credit: Karen England

Acanthomintha illicifolia San Diego thornmint, a success story!


San Diego Thornmint, Acanthomintha illicifolia, is one of Mark’s conservation success stories. The process takes a very long time. They partnered with the San Diego Zoo’s rare plant program for the thornmint project. It began by collecting seeds – 10% from the mother plants. Once plants have grown from the mother seeds, they collect all the seeds. Some were given back to Parks and Rec for restoration efforts, the rest are kept for posterity. Thornmint is an annual whose population size is directly tied to the amount of rainfall received. The restoration project began in 2015 in an area in Mission Trails park that had once been home to a healthy colony of thornmint. Ten meter circle plots were established for monitoring. All thornmint plants in the monitor circle were counted by hand. The April 2019 results were very positive. There were 250 plants in the seeded area as well as 49 plants that were not seeded. Non-native species coverage was low at 2%, while the native species coverage was robust at 45%.


The Otay Tarplant is another success story Mark shared to illustrate how the amount of rainfall that falls has such an impact on native plant populations. In 2018 his group counted 388 plants over an area of about 1 acre. In 2019 there were 7.6 million plants covering an area of 14 acres. A sample plot is chosen by throwing a hula hoop into the monitored area. Plants were hand-counted within that sample plot. There were 33,000 Otay Tarplant plants counted in that sample plot. That number was used to determine the total plant count in the area.


Under his Vernal Pool Conservation Program he monitors 968 vernal pools in around 40 different areas. Vernal pools are created when a clay lens develops under an area of soil. This prevents water from percolating into the base soil. He monitors 5 plant species are monitored in the vernal pools. These pools pop out of nowhere when it rains – the rest of the year they are dry as a dust. There are plant species existing in San Diego vernal pools that do not exist anywhere else in the world. Mark feels his responsibility for these rare plants deeply, as he realizes if we lose them here, they are gone for good.


Mark suggested that a great place to see wildflowers is in Mission Trails Park north of Highway 52. Mid-May should be a good time as long as we get some rain over the next several months!

Naturalist is a joint initiative of the California Academy of Sciences and the National Geographic Society.
Mark recommends we all use iNaturalist.org to become citizen scientists!

Photo credit: Janet Ward
Aloe in bloom.


Photos by Janet Ward from the January meeting. From left to right Camellia japonica 'Kramer's Supreme', Camelliea j. 'Elegans', and Rosa 'Mr. Lincoln'.

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