Invasive Plant Species of Big Island Isabella Will Pathfinder Hawaii Trip 2018 1
2 While on the Big Island: We should be able to see some of these invasive plants, possibly even in environments where they have overtaken native populations The following plants are the primary targets of the Big Island Invasive Species Committee: Barbados gooseberry, Cotoneaster, Dahoon Holly, Jerusalem Thorn, Princess Tree, Rubber Vine, Pampas Grass, Smokebush, Photinia, Wax Myrtle, Miconia, and Ginger A couple of these plants form berries and flower in the winter, so keep an eye out for them!
3 Barbados gooseberry (Pereskia aculeate) Family: Cactaceae Capable of adapting to many environmental changes and conditions which is what makes it so invasive Spreads through water, birds, animals, and humans. Spiny plant that climbs up walls and trees Photo by: World of Succulents
4 Barbados gooseberry (Pereskia aculeate) Takes over fruit trees native to Big Island and makes it hard to pick the fruits Detached parts of the plant live and can form their own roots, developing new plants Photo by: World of Succulents
5 Cotoneaster (Cotoneaster pannosus) Multi-stemmed shrub that can grow up to 10 feet tall Clusters of white, five-petaled flowers Invades pasture and native rain forests Very adaptable and readily germinates even in the shade Easily characterized by its red, round fruits Photo by: Gardening Know How
6 Cotoneaster Photo by: Echter s
7 Dahoon Holly (Ilex cassine) Lives in swampy areas or wet locations Notable characteristic is its white flowers and clusters of red or orange berries in the winter that we may even encounter! Elevation from 0 to 3,000 feet Spreads in wet environments and displaces native plants in the process Photo by: Environmental Horticulture
8 Dahoon Holly Photo by: Meadow Beauty Nursery
9 Jerusalem Thorn (Parkinsonia aculeate) Has green bark, spiny and needle-like bristles Its fruits are purple-brown lumpy pods that contain dark brown seeds Grows from elevation of 500 to 5,000 feet Reproduces very rapidly and displaces native plants Spreads through water and during floods Photo by: San Antonio River Authority
10 Jerusalem Thorn Photo by: Hawaii.gov
11 Princess Tree (Paulownia tomentosa) Densely branched medium sized tree that grows to be 30-60 tall Flowers are fragrant, pale violet, and trumpet shaped. Its fruit are brown capsules that contain thousands of winged seeds Grows from 0 to 4,500 feet Photo by: DHgate.com
12 Princess Tree (Paulownia tomentosa) Reproduces very rapidly: 20 million seeds per year Root sprouts can grow 15 feet in one year Introduced from East Asia Photo by: Yamina Collectors Nursery
13 Rubber Vine (Cryptostegia madagascariensis) Woody vines grow up to 45 feet in length Flowers are white-lavender and are funnelshaped Fruit is a 2-3 inch long oval follicle Seeds are white and feathery Photo by: Northern Territory Government
14 Rubber Vine (Cryptostegia madagascariensis) Grows at elevations between 0 and 2,100 feet Vines smother native trees and seeds are dispersed with the wind. They can germinate on lava flows Secretes a white toxic sap Photo by: Top Tropicals
15 Pampas Grass (Cortaderia spp.) Large, tall grass that can grow up to 10 feet tall White, pink, or yellow flowers that are held above the leaves Fruit is silver-pink with bristles Grows from 0 to 4,000 feet elevation Forms large clumps, displacing native vegetation Increases the risk of fire in native forests because of its flammable nature
16 Pampas Grass Photo by: Gardening Express Photo by: Amazon.com
17 Smokebush (Buddleja madagascariensis) Vine-like shrub that grows up to 25 feet high Fragrant orange/yellow flowers Whitish-hairy leaves Fruits are white-purple berries Grows at elevations between 0 and 4,000 feet Form dense thickets White powder growing along its stem can cause allergic reactions
18 Smokebush Photo by: Lucid Key Server
19 Photinia (Photinia davidiana) Photo by: Deelish Garden Centre Evergreen broad leaf shrub Leaves are characterized by pink-bronze tones Flower is white and grows in clusters Fruit are small berries that turn red upon maturation Grows at elevations between 3,000 and 6,000 feet Comes from China
20 Photinia Photo by: Landscape Plants
21 Wax Myrtle (Morella cerifera) Leaves have leathery texture and serrated edges Flowers are small and fragrant Fruit is round with a waxy coating Roots contain a fungus that fixes nitrogen, which should theoretically be helpful, but this is not good for native forests Photo by: AustinTexas.gov
22 Wax Myrtle (Morella cerifera) Native plants grow in nitrogen poor soils. Adding nitrogen causes invasive plants to grow faster than the native ones Plant is a fire hazard Photo by: Pinterest
23 Miconia Fast growing weedy tree that is 13-50 feet in height Leaves are incredibly large 3 feet long and 1 foot wide Underside of leaf is purple Shade it produces kills other plants and the roots are very shallow so they cause soil erosion and landslides
24 Miconia
25 Ginger (Hedychium gardnerianum) Grows quickly and chokes out native plants Came to Hawaii as a result of escaping local gardens Stamen is bright red and easily pointed out They are yellow and fragrant when older.
26 Importance Invasive plants affect the life and survival of other organisms in the native area Most invasive plants do not have any natural predators and can spread even further They also can put native plants in danger as a result of changing soil composition, sometimes flammable properties, and overgrowth It is up to the human populations to remove them and stop their growth
27 Can You Name them? A) B) C) D) E) F)
28 Answers! A) Jerusalem Thorn B) Cotoneaster C) Barbados gooseberry D) Dahoon Holly E) Smokebush F) Princess Tree
29 References http://www.biisc.org/ https://www.se-eppc.org/manual/princess.html https://www.wildflower.org/plants/result.php?id_plant=paac3 https://plants.ces.ncsu.edu/plants/all/photinia-davidiana/ https://dlnr.hawaii.gov/hisc/info/invasive-species-profiles/miconia/