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1.15: Secondary Growth

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    Cambium growth layers are the main generators of dicot new wood cells (xylem) and inner bark tissues (phloem) in perennial plant species. Secondary growth is caused by secondary tissues in woody dicotyoledon and gymnosperm plant species getting wider stems, branches, and roots. Furthermore, almost no secondary growth is observed in herbaceous plants and most monocotyledons. Secondary growth, in general, is a result of two lateral meristems (cambiums):

    1. Vascular cambium: produces secondary xylem and secondary phloem
    2. Cork cambium: produces periderm (substitutes epidermis)

    Perennial trees can live for centuries including bristle cone pines, cypresses, and gingkoes.

    \(\PageIndex{1}\). Student Learning Outcomes (SLOs)

    • SLO 15.01: Apply the best practices for learning secondary growth in select plants
    • SLO 15.02: Define vascular cambium and secondary growth
    • SLO 15.03: Explain what are tree rings, wood, and bark
    • SLO 15.04: Describe the characteristics of bark and its components
    • SLO 15.05: Identify given plant species with their scientific names based on their key features
    • SLO 15.06: Explain how to determine the age of a tree
    • SLO 15.07: Describe dendrochronology and its importance

    \(\PageIndex{2}\). Big Picture


    \(\PageIndex{3}\). Vocabulary and Key Concepts


    \(\PageIndex{4}\). Test Your Knowledge

    • Assessment 15.3.1: TRUE or FALSE: World’s largest tree is General Sherman tree (Sequoia giganteum) that is located in California (H: 84m, W:30m).
    • Assessment 15.3.2: TRUE or FALSE: World’s tallest tree is Hyperion (Sequoia sempervirens) that is located in California (H: 116m).
    • Assessment 15.3.3: TRUE or FALSE: Sugar maple sap is used to make syrup.
    • Assessment 15.3.4: TRUE or FALSE: Briar wood is resistant to fire (used in pipes)

    \(\PageIndex{5}\). Can You Spot These Plants?


    \(\PageIndex{6}\). Check Your Answers

    1. TRUE
    2. TRUE
    3. TRUE
    4. TRUE

    This page titled 1.15: Secondary Growth is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Gokhan Hacisalihoglu (Florida State Open Publishing) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.