Landscape July 2019 L-45

Expanding Tree Diversity in Hawai‘i’s Landscapes: Silver Buttonwood, Conocarpus erectus var. sericeus Richard A. Criley Department of Tropical Plant and Soil Sciences

uttonwood occurs as a shrub or small tree in south Florida and the Caribbean islands. While itB can reach 60 ft. in height, generally it is about 25–35 ft., with an open crown of about 20–25 ft. The twisted trunk belies the species name, erectus, which implies upright growth. The wood is very hard and is used in carvings. The silver-leaf form is more popular than green for landscaping.

Recommended Use in Landscapes • As a shrub for hedges • Screen and windbreak • Accent • Small street tree

Distribution • Tidal areas of the Caribbean, Mexico, and the west coast of Africa. Silver buttonwood as a street tree Propagation Techniques • Cuttings • Seed (silver form does not come true from seed) • Air layers

Cultural Requirements and Tolerances • Requires frequent pruning to achieve a dense crown • Wind tolerant • Tolerant to diverse soils • Tolerant to salt spray and saline soils • Does well in wet areas but is listed as low water use

Flower and Fruit Characteristics • Flowers are borne in dense clusters of small indi- vidual flowers. Silver buttonwood flowers

Published by the College of Tropical Agriculture and Human Resources (CTAHR) and issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in co- operation with the U.S. Department of Agriculture, under the Director/Dean, Cooperative Extension Service/CTAHR, University of Hawai‘i at Mānoa, Honolulu, Hawai‘i 96822. Copyright 2018, University of Hawai‘i. For reproduction and use permission, contact the CTAHR Office of Communication Services, ocs@ctahr.hawaii.edu, 808-956-7036. The university is an equal opportunity/affirmative action institution providing programs and services to the people of Hawai‘i without regard to race, sex, gender identity and expression, age, religion, color, national origin, ancestry, disability, marital status, arrest and court record, sexual orientation, or status as a covered veteran. Find CTAHR publications at www.ctahr.hawaii.edu/freepubs. UH–CTAHR Expanding Tree Diversity in Hawai‘i’s Landscapes: Silver Buttonwood L-45 — July 2019

• Mature fruits are reddish, up to ¾ inch diameter, and look like leather buttons.

Leaf Characteristics • Green or silver-gray and fuzzy • Simple with smooth margin and pointed tip • Arranged alternately on the branch

Advantages for Use in Landscapes • The silver form is attractive when lighted at night. • Good beach plant • Can be used in xeriscapes once established • HPWRA = 4 (evaluate for invasiveness)

Disadvantages for Use in Landscapes • Crown tends to be open unless managed by prun- ing to encourage branching. • Basal suckering • Occasional reversion to green form

Silver buttonwood as a street tree. Note suckering along the trunk.

Buttonwood trunk shows twisting habit and coarse ridges.

Reversion to green form can occur with severe pruning.

Buttonwood fruits

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