Presentation on theme: "Foliar Indicators of Age in Louisiana Native Dwarf Palmetto Plants"— Presentation transcript:
1 Foliar Indicators of Age in Louisiana Native Dwarf Palmetto Plants Jim Wandersee, Ph.D.William LeBlanc Alumni Association Professor of Biology EducationLSU Department of Curriculum & Instruction &LSU AgCtr Burden Research Center
2 Introduction Dwarf Palmetto (Sabal minor) is a native Louisiana plant Understory palm found in the Southeast in swamp forests and on floodplainsSlow growing to hundreds of years of ageFirst described in 1691 by Le Clercq in an account of La Salle’s explorations of the Mississippi River
3 Dwarf Palmetto Botanical Classification Family: Palmae Genus: Sabal Specific epithet: minor
4 The Palm Family (Palmae) Found in sub-tropics and tropicsThird-largest monocot familyContains >2,700 species in >200 generaGreatest diversity in SE Asia & Malaysia, Central America, African Congo region, and N. Madagascar (Uhl & Dransfield, 1987)
5 Range: Distribution of Sabal minor Coastal plains of the South Atlantic Seaboard and the states bordering the Gulf of MexicoLouisiana is the ONLY state to be completely included in its rangeStates partially within its range are NC, SC, GA, FL, AL, MS, & TX
6 S. Minor Inflorescence Structure & Fruit Flowering season:mid-June to July
7 Variablity in StatureSabal minor data recorded in the botanical literature suggest:Height MINIMA: ~40 centimeters (mature)Height MAXIMA: ~5.8 meters (mature)As a rule of thumb, height increases from east to west (e.g., Panhandle of Florida to West Texas).Caulescent populations have not been observed in the eastern half of its range (Ramp, 1989).
8 Research Program Goals To improve both scientific understanding and public understanding of one of Louisiana’s most widespread and “signature” native plant species, Sabal minor.
9 Research Target: Phase I To find the simplest way of estimating the age of individual Sabal minor plants—by investigating the predictive value of selected foliar variables that are supported by a review of relevant research literature in plant ecology and in horticulture.
10 Research Plots Phase I: Full Sun Specimens Will yield a conservative age estimatePlot #1: 3-acre Barton arboretum area of BRC~40 individuals of varying pre-reproductive agePhase II: Forest Understory SpecimensIn full range of stages [#1-#12] of development3 native population plots within BRC’s 100-acre forest
11 Methods Foliar Variables under study: Leaf surface area for largest leafMaximum leaf thickness for largest leafLeaf oven dry mass (estimated by regression equation via petiole blade-basal width for largest leaf)Total number of leaves per plantTotal number of leaf scars perplant, plus (see next slide)
12 Methods continued Foliar Variables under study: Munsell Plant Tissue Color Chart ratings for the largest and smallest leavesLeaf nutrient analysis of 21 elements via ICP spectroscopy for largest and smallest leavesThese variables will be correlated to historically established, age-benchmark specimens, and to pre- and post-reproductive features described by Ramp (1989).
13 Researcher Memberships American Association for the Advancement of ScienceBotanical Society of AmericaCrosby ArboretumLSU 15º LaboratoryNational Association of Biology TeachersNational Tropical Botanic GardenInternational Palm SocietyRoyal Horticultural Society