Source: UNIVERSITY OF GUAM UOG STATION submitted to
PROPAGATION AND ESTABLISHMENT OF NATIVE TREES AND SHRUBS FOR LANDSCAPING AND REFORESTATION
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
MCINTIRE-STENNIS
Reporting Frequency
Annual
Accession No.
0192465
Grant No.
(N/A)
Project No.
GUA00151
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Jul 1, 2002
Project End Date
Jun 30, 2007
Grant Year
(N/A)
Project Director
McConnell, J.
Recipient Organization
UNIVERSITY OF GUAM UOG STATION
(N/A)
MANGILAO,GU 96913
Performing Department
EXPERIMENT STATION
Non Technical Summary
Most plants used for landscaping and reforestation on Guam are non-native. Development of native plant materials for the se purposes will help preserve the local environment and provide more suitable plant material for the local landscape industry. Langiti (Ochrosia mariannensis A. DC (Apocynaceae)) is a small to medium tree that grows on limestone. The leaves are an attractive glossy dark green in loose whorls. The flowers are small and white, but the 5 cm fruits are attractive and may be either yellow or bright red. This is a very attractive tree to incorporate into the andscaping palette. It is an edge species and not an understory species. It is anticipated that this tree will be successful as a specimen tree. The scaevola cultivars will be named and released to the public this year. The additional flower color patterns will expand that plant palette of native plants for Guam.
Animal Health Component
(N/A)
Research Effort Categories
Basic
(N/A)
Applied
100%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
20206401060100%
Knowledge Area
202 - Plant Genetic Resources;

Subject Of Investigation
0640 - Tropical forests;

Field Of Science
1060 - Biology (whole systems);
Goals / Objectives
Collect native tree and shrub species that have a potential for use in reforestation or landscaping. 2. Investigate pratical methods for propagating selected species. 3. Monitor the growth and evaluate selected plant material. 4. Monitor establishment of plants in the field.
Project Methods
Collect native tree and shrub species. Surveys of forested areas will be conducted to collect plant materials from native populations of trees and shrubs. The selected plant material will be propagated and established in a nursery for evaluation. The plant material will be located within the nursery in appropriate micro-climates that reflect their original habitat. For example, understory plants will be grown in shade. Plants that show poor seed germination results will be noted for further investigation. 2. Investigate practical methods for propagating. Plant materials that are selected will be used in further investigations to determine efficient ways of propagating and establishing particular species. Seed germination and cuttings will be the methods of propagation for this objective. Seeds will be germinated using various pre-treatments to speed germination and to increase the percentage of germination. Cuttings will be propagated under mist. The mist timing may be modified depending on the prevailing weather and the type of cutting. The actual method of propagation will vary with the species. Rooting hormones will be applied at different rates in an effort to accelerate the propagation of cuttings. Different age cuttings will be taken and compared for time to root and survival of cuttings. Several different media will be used to determine the most suitable propagating medium for each type of plant material. Once the seedlings and/or cuttings are established, the plant material will be transplanted to different nursery locations to determine the ranges of suitable habitats. Initially, the plants will be established in microclimates resembling their natural habitat as reported by various authors. 3. Monitor the growth and evaluate selected plant materials. Data will be collected on height, girth and branching habit. Other criteria for evaluating plants will vary with the intended use. The plant material will be evaluated for use based on adaptations to environmental conditions, some aesthetic quality or some functional use such as shading or as a living barrier. Conditions that are often problem areas for plants include beach areas (salt spray and sandy soil) and areas with shallow soil or steep slopes. Aesthetic qualities include fragrance, attractive habit, flower, or foliage. Functional uses include both historical uses such as for tools and construction, and functional landscape uses including living barriers and supplying shade. If the plant is deciduous, the time of leaf drop will also be noted. 4. Monitor establishment of plants in the field. After the plants are propagated, they need to be hardened to prepare them for transplanting to the field. This is a critical stage. Some plant materials which propagate readily are much more difficult to establish in the field. Wind damage has proved to be the greatest problem in establishing the plants in the field. Various approaches will be utilized to address this problem when transplanting the trees to open areas. Windbreaks and screens will be used to reduce the exposure to wind. These exposed trees will be compared to material grown as understory plants.

Progress 07/01/02 to 06/30/07

Outputs
OUTPUTS: 1. Surveys were conducted to identify distinctive island flora of Guam that can be used in the urban landscape. 2. Experiments were conducted to determine methods of propagating selected species. 3. Services were provided to local nurseries through consulting to give advice on plant palettes for revegetation projects and propagation methods to use to produce sufficient quantities of plant material for reforestation. 4. Information obtained from this project was used to produce educational materials used in undergraduate and graduate courses. These courses included Plant Biology and Urban Landscape Management. PARTICIPANTS: Principle Investigator: James McConnell Undergraduate Student: Jean-Marc Guedon TARGET AUDIENCES: Landscape Management Systems and Bob's Nursery obtained information from this project for the propagation and production of Guam's flora. Students in the undergraduate classes: Plant Biology, Introduction to Horticultural Science and the graduate course Urban Landscape Management. This research was the basis for the development of the Urban Landscape Management course. Extension associates have consulted with the PI to obtain information and advice on identification and propagation of native plants. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Information obtained from the research of this project is being used to preserve the island's distinctive flora by promoting their use in urban settings and in reforestation projects. To develop urban and reforestation projects, evaluations for plant selections become crucial for long-term sustainability. Guam has two distinct geological regions: 1) porous limestone and 2) volcanic clays. Besides geological substrate, selection of plant materials is also based on drainage, sunlight, and wind/salt and shade tolerance. Selection of plants based on their growing factors and pairing them to the environmental factors of the planting site is an essential association for success. Guamia mariannae is a small, primary forest understory species that grows in low light and high humidity levels on well-drained limestone soils. This species does well in wind sheltered yards on limestone substrates. For revegetation areas where limestone soils have been scraped bare Neisosperma oppositifolia works well as a pioneer plant. Not only does N. oppositifolia grow in degraded sites but it also produces copious amounts of leaf litter thereby creating a layer of organic matter to rebuild soils. Lastly a species that tolerates high wind and salt spray, Ochrosia mariannensis grows on cliff areas and near the seashore. Ochrosia mariannensis has proven its worth growing in the harsh environment of highway strip medians and is also a contributor to revegetation sites. Scaevola sericea is another pioneer species that is capable of establishing in soilless areas. It was discovered that there is variation in the flower color. Selections were made and were propagated and distributed for use in the urban landscape. Elaeocarpus joga is a handsome dominant tree species which has reduced in the number in forested areas. Propagation methods were developed for producing plants of selected trees using cuttings. Bikkia tetrandra is an attractive shrub which naturally germinates and establishes on limestone rock which can be easily placed in the landscape. Through the accurate selection of native and endemic species to mimic their growing sites the success and promotion of the islands native flora may help offset the effects of habitat loss.

Publications

  • Gutierrez, L. and J. McConnell. 2008. Selection and promotion of native and endemic plants through usage in reforestation and landscape projects on Guam. Conference Proceeding (abstract) HortScience 43(4): 1265.
  • McConnell, J. 2005. Release of New Scaevola sericea cultivars. Conference Proceeding (abstract) HortScience. 41(4) 1041.
  • McConnell, J. 2005. Guam Native Trees and Shrubs for the Landscape. Conference Proceeding (abstract) HortScience. 40(4):996.
  • Guedon, Jean-Marc G., and J. McConnell. 2004. Rooting of Elaeocarpus joga, an Ornamental Tree indigenous to Guam. Conference Proceeding (abstract) HortScience 39(4) 787.


Progress 01/01/06 to 12/31/06

Outputs
Seedllings of Eleaocarpus joga were established in shallow Guam Cobbly Clay soil. Variation in growth characteristics are obvious in the seedling population. The site is exposed to natural wind conditions. Mealybugs and thrips were observed on the trees which results in severe dieback of branches. Protection from bush cutter damage is critical to the survival of the trees. The trees develop a windswept canopy shaped by the prevailing winds. There was one hundred percent survival of planted trees.

Impacts
Developing recommendations for using native plants in the landscape will lessen the risk of establishing exotic species. The selected native plants are being established in landscapes around the island.

Publications

  • No publications reported this period


Progress 01/01/05 to 12/31/05

Outputs
Seeds of Ochrosia mariannensis A. DC (Apocynaceae) were collected and arebeing germinated. These small trees will be planted in the field for testing as specimen trees. Five selections of Scaevola serica were made and are being propagated for release to the public. four of these selections have magenta bands or spots on the flower petals in contrast to the usual white flower. One selection has a floral fragrance.

Impacts
Langiti (Ochrosia mariannensis A. DC (Apocynaceae)) is a small to medium tree that grows on limestone. The leaves are an attractive glossy dark green in loose whorls. The flowers are small and white, but the 5 cm fruits are attractive and may be either yellow or bright red. This is a very attractive tree to incorporate into the andscaping palette. It is an edge species and not an understory species. It is anticipated that this tree will be successful as a specimen tree. The scaevola cultivars will be named and released to the public this year. The additional flower color patterns will expand that plant palette of native plants for Guam.

Publications

  • McConnell, James 2005. Guam Native Trees and Shrubs for the Landscape. HortScience 40:996.


Progress 01/01/04 to 12/31/04

Outputs
A cutting experiment was repeated to verify the results. Stem cuttings of E. joga were taken from hardwood, semihardwood, or softwood and treated with acid or salt forms of IBA or NAA at several concentrations. The cuttings were treated with one of the following: acid form at 0.5 mL IBA/L plus 0.25 mL NAA/L, 1 mL IBA/L plus 0.5 mL NAA/L, 2 mL IBA/L plus 1 mL NAA/L; salt form at 1, 3, 8 g IBA/kg. Rooting after 8 weeks was compared among treatments. The salt form of the IBA treatment at 3 g times kg-1 produced the greatest rooting percentage, root number and length. The acid form containing both IBA and NAA produced the smallest average rooting percentage. Chemicals used Indole-3-butyric acid (IBA) Napthaleneacetic acid (NAA).Elaeocarpus joga Merr. is an attractive tree which is indigenous to the region. E. joga rooted cuttings were transplanted to root pruning pots in preparation for transplanting to the field. Trees previously planted in field locations suffer severe damage from thrips. Branches frequently turn red and die. Other E. joga were planted in either forested areas, open fields or intercropped with iron wood (Casurina esquisitefolia).

Impacts
Developing the ability to vegetatively propagating E. yoga will enhance its usage in the landscape by allowing plantings with uniform characteristics. This will allow the propagation of cultivars selected with superior characteristics.

Publications

  • Jean-Marc G. Guedon and James McConnell. 2004. Rooting of Eleaocarpus joga, an Ornamental Tree Indigenous to Guam. HortScience. 39(4):787.


Progress 01/01/03 to 12/31/03

Outputs
Elaeocarpus yoga Merr. is an attractive tree which is indigenous to the region. E. yoga has great potential for use as a specimen landscape plant and for reforestation. Variation in leaf shape, color and texture as well as variation in canopy characteristics makes it necessary to vegetaively propagate selections. Previously trees were only successfully propagated from seed. Hardwood, semihardwood and softwood cuttings were treated with acid and salt forms of IBA and/or NAA at several concentrations. The cuttings were treated with one of the following: acid form at 05 mL IBA/L + 0.25 mL NAA/L, 1 mL IBA/L + 0.5 mL NAA, 2mL IBA/L + 1 mL NAA/L; salt form at 1, 3, or 8 g IBA/kg. Rooting was compared after 8 weeks. The best rooting (occurred with the salt form of IBA at 3 g/kg. The acid form containing both IBA and NAA produced poorer results.

Impacts
Developing the ability to vegetatively propagating E. yoga will enhance its usage in the landscape by allowing plantings with uniform characteristics. This will allow the propagation of cultivars selected with superior characteristics.

Publications

  • No publications reported this period


Progress 01/01/02 to 12/31/02

Outputs
The characteristics of flower color and floral fragrance were found to show great variation in the natural populations of Scaevola sericea found in Guam. This resulted in the need to vegetatively propagate selections from these populations. A comparison of using various concentrations of IBA for propagating S. sericea was undertaken. Basal portions of terminal cuttings were treated with either 2000, 5000, or 10,000 ppm IBA dips for 5 seconds. The control was a water dip. The cuttings were placed in growing media consisting of peat-moss and perlite (1:2). Rooting was evaluated one month after treating. The control had the highest percentage of rooting (90%) The poorest rooting occurred in the 2000 ppm treatment. The quality of rooting was also highest in the control with a rating of 4.8 on a scale of 1 to 5 with 5 being the best. Collection of other species was hampered by storms which did significant damage to forested areas, preventing the collection of seeds and cuttings. Eleaocarpus joga is continuing to be evaluated as a landscape specimen plant. Establishment in the landscape as only been moderated successful. Wind damage and insect damage from thrips have caused severe damage.

Impacts
(N/A)

Publications

  • No publications reported this period