Plant Profile
Ischaemum byrone
Main Plant Information
Genus
Ischaemum
Species
byrone
Common Names
- Hilo beach grass
- Hilo ischaemum
- Hilo murainagrass
- Ischaemum
Synonyms
- Andropogon byronis
- Ischaemum lutescens
- Spodiopogon byronis
Names with Unknown Sources
- Hawaiian Shore-grass
Plant Characteristics
Distribution Status
Endemic
Endangered Species Status
Federally Listed
Plant Form / Growth Habit
- Non-Woody, Spreading
Mature Size, Height (in feet)
- Grass-like, Medium, 1 to 2.5
- Grass-like, Tall, Greater than or equal to 2.5
Life Span
Short lived (Less than 5 years)
Landscape Uses
- Accent
- Container
- Ground Cover
Source of Fragrance
- No Fragrance
Plant Produces Flowers
Yes
Flower Characteristics
Flower Type
Not Showy
Flower Colors
- Greenish-White
- Yellow
Additional Flower Color Information
Yellow, long bristles basally dark brown.
Blooming Period
- Year Round
Additional Blooming Period and Fruiting Information
The seed heads often split to form two separate heads, especially after seeds are ripe.
Leaf Characteristics
Plant texture
No data available.
Leaf Colors
- Light Green
Additional Leaf Color Information
The flat leaves are green with sometimes a bluish cast and no hairs.
Pests and Diseases
Additional Pest & Disease Information
Few pests seem to both this rare native grass. Black sooty mold can form at the base of the plants due to overwatering or excessive rainfall. [David Eickhoff, Native Plants Hawaiʻi]
Growth Requirements
Fertilizer
Light applications of a 13-13-13 slow release fertilize every six months. Foliar feeding in early morning with a water-soluble or an organic fertilizer (e.g. kelp or fish emulsion) at one-third to one-fourth the recommended strength every monthly or even every other month has proven beneficial. Do not over fertilize this native grass.
Pruning Information
Not much maintenance required except to remove spent seed stems. The thatch (dead grass) can be cleared from the base if black sooty mold appears to be problematic.
Water Requirements
- Dry
Additional Water Information
Does best on the dry side with frequent drenchings of water.
Soil must be well drained
Yes
Light Conditions
- Full sun
- Partial sun
Additional Lighting Information
Does best in full sun.
Spacing Information
Hilo ischaemum spread by stolons, but will also drop seed beneath mother plants which will germinate. Space plants from one to two feet apart. They will grow together. [David Eickhoff, Native Plants Hawaiʻi]
Tolerances
- Drought
- Wind
- Salt Spray
- Heat
Soils
- Sand
- Cinder
- Organic
- Coral
Environmental Information
Natural Range
- Kauaʻi
- Oʻahu
- Molokaʻi
- Maui
- Hawaiʻi
Natural Zones (Elevation in feet, Rainfall in inches)
- Less than 150, 0 to 50 (Dry)
- Less than 150, 50 to 100 (Mesic)
Habitat
- Terrestrial
Additional Habitat Information
Uncommon to rare throughout its range. It is found among rocks near the ocean and sometimes further inland up to 250 feet. This grass is most often found near naupaka kahakai, perhaps forming a symbiotic relationship. [4]
Historically, Ischaemum byrone was found throughout the main islands: Kauaʻi; Oʻahu; northeast coast of Molokaʻi; east Maui; and the eastern and inland portion of Hawaiʻi Islandi including Hilo Bay. [5] Now extirpated on Oʻahu. [1]
Special Features and Information
General Information
Ischaemum is a genus of about 60 species in the Poaceae, or Grass family. Ischaemum byrone is endemic to the Hawaiian Islands. There are some 50 species of native grasses in the Hawaiian Archipelago, of which at least forty are endemic.
Two other non-native, naturalized Ischaemum species, I. indicum and I. timorense, occur on East Maui.
Etymology
The generic name Ischaemum is derived from the Greek ischiamos , to quench blood flow, with unknown application.
The specific epithet byrone was named after Byron’s Bay, now Hilo Bay, on the island of Hawaiʻi. [5] Byron’s Bay was named for Captain George Anson Byron (1789-1868), a British naval officer, and the seventh Baron Byron, cousin of the poet George Gordon Byron. Admiral Byron came to the islands on the H. M. S. Blonde to bring to their final resting place the remains of Kamehameha II and his queen, Kamāmalu, who contracted and died of measles on a visit to Great Britain.
Background Information
Hilo ischaemum is an endangered species.
Presumably this grass has spread to the Cook Islands and the Austral Islands by migratory birds from Alaska, such as the Pacific Golden plover and Bristle-thighed curlew. [2]
Early Hawaiian Use
No Hawaiian name or recorded uses are known.
Modern Use
Our native grasses and sedges are, for the most part, underrated and often overlooked in native landscapes.
Native grasses need to be given more attention as an important kamaʻāina addition to our landscapes and yards. Although Hilo ischaemum is a rare native grass, it is easy to grow from stolons or by seed. This is a wonderful accent plant for other native shrubs and trees in open, sunny or part sunny locations.
Additional References
[1] “5-Year Review: Ischaemum byrone” by the U.S. Fish & Wildlife Service, page 2.
[2] http://cookislands.bishopmuseum.org/species.asp?id=6276 [Accessed 6/8/11]
[3] Hawaii Nature Notes, Vol. 5, November 1953, No. 2 http://www.nps.gov/history/history/online_books/hawaii-notes/vol5-2c.htm [Accessed 6/8/11]
[4] Kahu Wai Project http://www.kahuwaiproject.org/specieslist.html [Accessed 6/8/11]
[5] “Recovery Plan for the Big Island Cluster” by the U.S. Fish & Wildlife Service, pages 63, 65.
