Terrestrial vegetation monitoring at Fort Matanzas National Monument: 2019 data summary

Abstract

The Southeast Coast Network (SECN) conducts long-term terrestrial vegetation monitoring as part of the nationwide Inventory and Monitoring Program of the National Park Service (NPS). The vegetation community vital sign is one of the primary-tier resources identified by SECN park managers, and it is currently conducted at 15 network parks (DeVivo et al. 2008). Monitoring plants and their associated communities over time allows for targeted understanding of ecosystems within the SECN geography, which provides managers information about the degree of change within their parks’ natural vegetation. 2019 marks the first year of conducting this monitoring effort at four SECN parks, including Fort Matanzas National Monument (FOMA). Nine vegetation plots, located on Anastasia and Rattlesnake Islands, were established at Fort Matanzas National Monument in June. Data collected in each plot included species richness across multiple spatial scales, species-specific cover and constancy, species-specific woody stem seedling/sapling counts and adult tree (greater than 10 centimeters [3.9 inches {in}]) diameter at breast height (DBH), overall tree health, landform, soil, observed disturbance, and woody biomass (i.e., fuel load) estimates. This report summarizes the baseline (year 1) terrestrial vegetation data collected at Fort Matanzas National Monument in 2019. Data were stratified across two dominant broadly defined habitats within the park (Maritime Upland Forests/Shrublands and Maritime Open Uplands). Noteworthy findings include: Eighty-two vascular plant taxa (species or lower) were observed across nine vegetation plots, including eight species not previously documented within the park. The most frequently encountered species in each broadly defined habitat included: Maritime Upland Forests and Shrublands: saw palmetto (Serenoa repens), yaupon (Ilex vomitoria), southern/eastern red cedar (Juniperus silicicola + virginiana), American beautyberry (Callicarpa americana), and American burnweed (Erectites hieraciifolius). Maritime Open Uplands: sea oats (Uniola paniculata), earleaf greenbriar (Smilax auriculata), and dixie sandmat (Euphorbia bombensis). ne non-native species, Brazilian pepper (Schinus terebinthifolia), categorized as invasive by the Florida Exotic Pest Plant Council (FLEPPC 2019) was encountered in one Maritime Upland Forest and Shrubland plot during this monitoring effort. There were not any rare plants tracked by the Florida Department of Agriculture and Consumer Services (FDACS 2020) found during this monitoring effort. All plants located in these monitoring plots are fairly common throughout Florida, as well as across the Southeast Coast. Three species observed, however, are on the FDACS 2020 list of commercially exploited plants within the state. These include saw palmetto, cinnamon fern (Osmundastrum cinnamomeum), and coontie (Zamia integrifolia var. umbrosa). Southern/eastern red cedar and cabbage palmetto (Sabal palmetto) were the most dominant species within the tree stratum of the Maritime Upland Forest and Shrubland habitat type. Species that dominated the sapling and seedling strata of this type included yaupon and cabbage palmetto. More than 75% of the trees measured in the parks Maritime Upland Forest and Shrubland habitat type were alive and experiencing healthy vigor. Of the 22 trees that were dead, more than 50% of those were southern/eastern red cedar. Most of those individuals that were observed with moderate or severe decline and greater than 50% dieback were southern/eastern red cedars. Although red bay (Persea borbonia) was identified as one of the “principal understory tree” species within Fort Matanzas National Monument’s maritime forests in 2004 (Zomlefer et al. 2004), tree-sized individuals were rarely detected on plots during this monitoring effort. This may be in part due to the detection of laurel wilt disease within St. Johns County in 2006 (USDA 2021). Based on the low detection...