Identification of Invasive Weeds in Florida s Natural Areas 4/21/09. Roy Beckford Agriculture/Natural Resources Agent UF/IFAS

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1 Identification of Invasive Weeds in Florida s Natural Areas 4/21/09 Roy Beckford Agriculture/Natural Resources Agent UF/IFAS

2 Where Do Problem Plants Come From?

3 Invasive Plants An army of invasive plant and animal species is over-running the United States, causing incalculable economic and ecological costs. Florida is a beach head for the invasion. DON SCHMITZ Florida Department of Environmental Protection

4 Why should anyone care about identifying invasives? Timber production, aesthetics, recreation, wildlife, or a combination of many benefits, can all be affected by these plant invasions 46% of the federally listed threatened and endangered species in the United States are considered to be imperiled in part due to impacts of invasive species $3-5 trillion lost annually to the impacts and management of invasive species

5 The Displacement Problem Most have low use and feeding levels by native insects Most are rarely grazed upon by larger herbivores Without the herbivores, the carnivores disappear The subsequent displacement of native keystone species result in disruption of an ecosystem's natural food web

6 Natural Areas Natural area An area of land or water that either retains or has reestablished the characteristics of natural communities and provides environmental, scientific, or aesthetic benefits. It is important to preserve Florida s native habitats for - Historical significance - Ecological equilibrium - To protect species, water quality and quantity

7 Where to look for invasive species The first place you find these plants is in areas of human activity, such as: Forest boundaries Common dumping sites Old home sites Roadways, trails and ditches Disturbance areas-timber sales, mining sites, firelines Campsites

8 The big weed problem

9 What s a weed? Spray Man This weed is good, Mon! If it s green, it s a weed, Man!

10 Weeds, Exotics & Invasives A weed is a plant growing where it is NOT wanted An exotic or non-native plant is one which was introduced to a new area (Florida) purposefully or accidentally, from a natural range outside of Florida An invasive species is one that physically displaces native plants AND disrupts natural processes

11 Invasives In order maintain or restore natural communities, it is often necessary to control invasive species. Invasive species are weeds which are undesirable, requiring the action of man to control or eliminate.

12 Identification, identification Learn the basics Identify native species List native species See what invasive species are close by Get help from local resource agencies

13 Basic Plant Knowledge - Classification Monocotyledons (Monocots) Dycotyledons (Dicots) Flowering Plants 1 Ferns Non-Flowering Plants 2

14 Monocotyledons One of the two main types of flowering plants, monocots are plants that develop a single cotyledon (seed leaf) from the embryo at germination. They are nearly always herbaceous never forming true wood, have fibrous roots (no tap roots), and the leaves have parallel veins. Flower parts are usually in threes or multiples of threes.

15 Example of Monocots Wild Taro Colocasia esculenta

16 Another Example of Monocots Cogon grass Imperata cylindrica

17 Dicotyledons The second of the two main groups of flowering plants, dicots develop two (or more) cotyledons from the seed embryo at germination. May be herbaceous or truly woody, and roots may be fibrous or include a taproot. Dicot leaves usually have netted venation and the flowers are usually in fours or fives, or multiples of fours or fives.

18 Example of Dicots

19 Ferns Ferns do not have true leaves as many plants do, but structures called fronds. These fronds are split down into leaflets called pinnae. These fronds are green and the fern gets its food via photosynthesis. Ferns reproduce from spores and an intermediate plant stage called a gametophyte.

20 Example of Ferns

21 A Simple Leaf Single, undivided blade tip- the terminal point of the leaf. blade-the flattened, green, expanded portion of a leaf. margin- edge of a leaf. midrib-the most prominent central vein in a leaf. lateral veins-secondary veins in a leaf. petiole-the leaf stalk (connects blade to stem). stipules-leaf-like appendages (at the base of petiole of some leaves).

22 A Compound Leaf Blade divided into leaflets leaflet- secondary leaf of a compound leaf. rachis- an extension of the petiole bearing leaflets. petiolule-the leaflet stalk. petiole-the leaf stalk lateral veins-secondary veins in a leaf. stipules-leaf-like appendages (at the base of petiole of some leaves).

23 Leaf Arrangement (simple leaf) 1. Opposite Two leaves (a pair) per node, usually opposite each other.

24 Leaf Arrangement (simple leaf) 2. Alternate One leaf per node, usually opposite each other.

25 Leaf Arrangement (simple leaf) 3. Whorled Three or more leaves per node, usually opposite each other.

26 Leaf Arrangement (compound leaf) 1. Pinnate Leaflets arising from along both sides of the rachis.

27 Leaf Arrangement (compound leaf) 2. Palmate Leaflets arising from the same location at the top of the petiole.

28 Leaf Arrangement (compound leaf)

29 Leaf Arrangement (compound leaf)

30 Leaf shapes and arrangements Sword-shaped (ensiformis) Long, thin, pointed Cordate (cordata) Heartshaped Oblanceolate (oblanceolata) Top wider than bottom Lobed (lobata) With several points Trifoliate (trifoliata) Divided into 3 leaflets Pinnate (pinnata) 2 rows of leaflets Bipinnate (bipinnata) Each leaflet also pinnate Tripinnate (tripinnata) Each leaflet divided into 3 Palmate (palmata) Divided into many lobes Digitate (digitata) Divided into 5 lobes

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36 Identification of Invasive Plant Species Monocotyledons, Dicotyledons and Ferns

37 Monocotyledons One of the two main types of flowering plants, monocots are plants that develop a single cotyledon (seed leaf) from the embryo at germination. They are nearly always herbaceous never forming true wood, have fibrous roots, and the leaves have parallel veins. Flower parts are usually in threes or multiples of threes.

38 Asparagus fern Asparagus sprengeri Evergreen perennial herb from a crown of tuberous roots, to (2 ft) in height Flowers small, white or pinkish white, and fragrant Fruits a bright red berry Displaces native ground cover and understory shrubs

39 Air Potato - Dioscorea bulbifera Large, heart shaped simple leaves Leaf veins radiate from a single point Produces aerial tubers Small, greenish, fragrant flowers Invasive plant

40 Dioscorea sp. Dioscorea bulbifera Air potato Dioscorea alata Water yam Dioscorea oppositifolia Chinese yam

41 Taro (wild taro, dasheen) Colocasia esculenta Emersed plant, with arrowhead-shaped leaves and heartshaped leaf bases Flowers occur in small fingerlike spikes Fruits a small berry, in clusters on the fleshy stalk.

42 Cogon Grass Imperata Cylindrica NON-NATIVE grass; from extensive rhizomes 3-10 ft. tall; leaf blades hairy at base, tapering to narrow base Mid-vein off-center, margins sharp Inflorescence showy white, cylindrical, plumelike, hairy

43 Dicotyledons The second of the two main groups of flowering plants, dicots develop two (or more) cotyledons from the seed embryo at germination. May be herbaceous or truly woody, and roots may be fibrous or include a taproot. Dicot leaves usually have netted venation and the flowers are usually in fours or fives, or multiples of fours or fives.

44 Australian Pine - Casuarina equisetifolia Large evergreen tree reaching 90 feet in height Round, oval fruits that do not attract wildlife Single trunk, with drooping branches

45 Brazilian Pepper-tree - Schinus terebinthifolius Small tree, but may grow to 30 ft. tall. Short trunk usually hidden by dense intertwining branches Leaves have 3-13 leaflets, 1-2 inches long Glossy green to bright red clustered fruits

46 Mellaleuca - Melaleuca quinquenervia Tall tree with whitish, spongy peeling, manylayered bark Grows in both terrestrial and aquatic situations Fruits are short, cylindrical or squarish, woody capsules with many tiny seeds Small trees grow into almost impenetrable monocultures Target of a currently functioning biological control effort

47 Carrotwood Cupaniopsis anacardioides Evergreen tree; has four-inch-long, glossy, dark green, divided leaflets Fruits are round, irregular, green to orange Popular in many yards and is used as a small to medium-sized street tree spaced about 20 feet apart.

48 Chinese Tallowtree - Triadica sebifera L. Small to medium sized deciduous tree (Nicknamed popcorn tree) It is monoecious, producing male and female flowers on the same plant. Tallowtree is toxic to animals and humans. The Fruit capsule has three locules (compartments) turning from green to black upon maturity. The capsule walls are eventually shed exposing the white seeds.

49 Earleaf Acacia -Acacia auriculiformis Evergreen tree that grows to 50 ft. tall Has blade-like, slightly curved leaves Fruit a flat, oblong pod, twisted at maturity, splitting to reveal flat black seeds, attached by orange, string-like arils.

50 Castor Bean - Ricinus communis Hardy plant that grows into small trees in disturbed sites Rounded fruits with multiple hairy spikes Poisonous seeds contain ricin One milligram of ricin can kill an adult

51 Downy Rose Myrtle - Rhodomyrtus tomentosa Evergreen shrub that usually grows to 6 ft. tall Can grow into large monocultures Flowers profusely in the spring (rose-pink) Bluish-purple globose berry about 1/2 in. across, that looks similar to blueberry but more oblong.

52 Rosary Pea - Abrus precatorius High-climbing, twining, or trailing woody vine with slender herbaceous branches. Flowers shaped like pea flowers, Fruit a short, oblong pod, splitting before falling to reveal 3-8 shiny hard seeds

53 Tropical Soda Apple Solanum viarum Bushy, prickly herbaceous perennial, to 2 m (6 ft) tall, Noxious weed, having highly viable seed, can infest a pasture or native area within 1 to 2 years The entire plant, including stems and leaves, has thorn-like prickles

54 Ferns Ferns do not have true leaves as many plants do, but structures called fronds. These fronds are split down into leaflets called pinnae. These fronds are green and the fern gets its food via photosynthesis. Ferns reproduce from spores and an intermediate plant stage called a gametophyte.

55 Old World Climbing fern - Lygodium microphyllum Has two types of leaflets (one simple and unlobed, the other more convoluted with sporangia along its margin) Fern with climbing fronds Enables small ground fires to reach into tree canopies

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