Dendrology FOR 219. Tree Life Cycle. Floral Anatomy. How Is It All Arranged? 8/27/2018

Transcription

1 Dendrology FOR 219 Instructor: Dr. Jeremy Stovall Lecture 4: Anatomy II: Flower, Fruit, & Cone Morphology Tree Life Cycle Seed Production Seed Germination Reproductive Tree Seedling Flowering Tree Vegetative Growth 2 Floral Anatomy How Is It All Arranged? 3 1

2 Floral Anatomy PISTIL + STAMENS = PERFECT MISSING EITHER = IMPERFECT PISTIL + STAMEN + SEPALS + PETALS = COMPLETE MISSING ANY = INCOMPLETE Can a flower be perfect but incomplete? Can a flower be imperfect but complete? Complete / Incomplete Perfect / Imperfect 4 Floral Anatomy MOST COMMON One House Complete or, Perfect or, Imperfect flowers of both sexes Monoecious = both sexes on a tree 5 Floral Anatomy LESS COMMON 2 Houses Boxelder Willow Persimmon Holly Ginkgo Dioecious = tree either male or female 6 2

3 What Is a Seed? Embryonic Tissues + Storage + Protection 7 How Do Seeds Disperse? 8 How Long Do Seeds Last? Beal s 20 Bottle Experiment: Some seeds germinated after 120 years! 9 3

4 GERMINATION Radicle Roots Hypocotyl Shoot Epicotyl Leaves How Do Seeds Work? Cotyledons = Seed Leaves Dicotyledon = 2 cotyledons (almost all trees) Monocotyledon = 1 cotyledon (yuccas & palms) 10 Types of Germination GERMINATION Epigeal Cotyledons above ground (beech, basswood, maples) Hypogeal Cotyledons below ground (oaks, hickories) 11 How Do We Describe Seeds? 12 4

5 Seed = ripened ovule Fruit = ripened ovary Ovary wall develops into fruit wall (pericarp) Pericarp has three layers: the skin (exocarp) the often fleshy middle (mesocarp) and the membranous or stony inner layer (endocarp) Fruit vs. Seed 13 Fruits Fruit = scientific term Vegetable = culinary term If a vegetable has seeds, then it is also a fruit Tomato, corn, cucumber 14 Fruits Develop from Flowers A fruit is the state that the flower turns to during the ripening of the seeds 15 5

6 What Types of FRUITS Are There? Compound Fruits Multiple Aggregate Simple Fruits Dry Indehiscent Dehiscent Fleshy 16 What Types of FRUITS Are There? Dry, indehiscent Achene Samara Nut Dry, dehiscent Legume Follicle Capsule Fleshy Pome Drupe Berry Hesperidium 17 Small, one seed, unwinged Sycamore Achenes Sunflower another example 18 6

7 Winged seed Samaras Maples Ashes Elms Yellow poplar Hoptree Tree of heaven 19 A hard shelled exterior contains both the fruit and seed Oaks Hickories Birches Beech Chestnuts Buttonbush Basswoods Nuts (And Nutlets) 20 Some Nuts Include Accessory Tissues Glans The involucre of bracts is found as a acorn cap Pseudodrupe Walnuts are a nut surrounded by a fleshy involucre Tryma Hickories are also a nut surrounded by a fleshy involucre Winged nut Hornbeam is a nut enclosed in a winglike bract 21 7

8 Splits on 2 lines Fabaceae (Legumes) Legumes 22 Splits on 1 line Magnolias Hercules club Follicles 23 Capsules Splits along 2 or more lines Crapemyrtle Sweetgum Buckeye Poplars Willows Catalpa Strawberry bush Ericaceae Tallowtree Paulownia 24 8

9 Fleshy, w/ woody or papery interior wall Pomes Apples Pears Hawthorns Juneberry 25 Stone Fruits Drupes Cherries Mulberries Sugarberry Sumacs Hollies Devil s walkingstick Caprifoliaceae Dogwoods Tupelos Lauraceae Osage orange Myrtles Fringe tree Privets Buckthorn Snowbell, Silverbells Sweetleaf Planertree 26 Many seeded & entirely fleshy Berries Pawpaws Persimmon Chittamwood Grapes 27 9

10 Leathery outer rind and radial sections Trifoliate orange Hesperidiums 28 Cluster of simple fruits from 1 flower Aggregate of follicles Southern magnolia Aggregate 29 Cluster of simple fruits from many flowers Multiple Multiple of achenes Sycamore Multiple of capsules Sweetgum 30 10

11 About Cones bract 31 About Cones apophysis umbo 32 Woody Cones 33 11

12 Pine Cones Take Several Years 34 Leathery Cones One Year 35 A lot About Seeds, But Male Tree Not Fruiting Now Too Young Rapidly Eaten 36 12

13 Some Fun Seed Facts pin cherry 37 Some Fun Seed Facts witch hazel 38 Some Fun Seed Facts table mountain pine Want to see? 39 13