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Why the Hawaii fire-plant question is upside-down
Because the fuel is the grass you stop planting, not the shrub you add. HWMO’s homeowner guide says invasive guinea and fountain grass ignite easily, re-sprout after fire, outcompete natives, and create a vicious fire cycle. HISC says wildfire frequency in the Hawaiian Islands is up 400% over the last century, and names fountain grass (Cenchrus setaceus) and guinea grass (Megathyrsus maximus) as high fire hazard. This directory has no species pages for those two taxa.
You are looking at a dry leeward slope of fountain grass and asking which Firewise shrub to plant into it. The opened Hawaii sources start with do not plant that grass, then weed it, then replant a low, drought-tolerant native ground cover. That is upside-down from a continental planting-list search.
This is not a Hawaii doorway. Hawaii plant evidence is USDA distribution. Live hwmo.org/wildfire-resilient-landscapes returned no usable body this session; the opened PDF is the HWMO guide.
Why it matters
A western on-list shrub planted into unmanaged guinea grass does not cancel the grass-fire cycle HWMO describes. HISC: over 25% of the islands are now covered by non-native grasses. HWMO: 18% of state land cover is nonnative grassland. Those are two documents. Neither is a California plant table.
Zone 0 is still not a planting list. HWMO’s fire-free 5 feet is their sentence, not this site’s Zone 0 rewrite.
A Nevada greenstrip is a 300-foot rangeland seed strip. HWMO’s replant sentence is native ground cover after weeding grass. Do not merge them.
How it works
HWMO guide (opened PDF):
- Non-native, fire-adapted vegetation has spread toward community boundaries.
- Guinea and fountain grass: spread easily; ignite easily; after fire, re-sprout and outcompete natives over a larger area. Vicious fire cycle.
- 18% of state land cover is nonnative grassland.
- Zone One: 30 feet from buildings. Remove dead vegetation and ladder fuels (at least 6 feet of separation). Fire-free area within 5 feet using non-flammable materials and/or high-moisture, drought-resistant vegetation.
- Zone Two: 30–100 feet. Mow annual grass to 4 inches.
- Weed guinea and fountain grass often. Consider replanting with low-lying, drought-tolerant, native ground cover. Never mow in dry vegetation.
HISC (opened HTML):
- Wildfire frequency +400% over the last century.
- Fountain grass (Cenchrus setaceus) and guinea grass (Megathyrsus maximus): High Fire Hazard; Ecosystem Modifier.
- Fountain grass: Hawaii Noxious Weed List (HAR 68); Weed Fire Risk Score 0.99; introduced as an ornamental, escaped by 1914; fire-adapted and fire-promoting; do not plant; burning is not recommended because it grows back rapidly.
- Non-regulatory list. Under severe conditions any vegetation can burn. Managed ranch grazing can reduce fine fuels.
This directory (honest gaps):
| Taxon | Hawaii sources | This site |
|---|---|---|
| Cenchrus setaceus fountain grass | HISC high fire hazard; HWMO names fountain grass | No species page |
| Megathyrsus maximus guinea grass | HISC high fire hazard; HWMO names guinea grass | No species page |
| Pennisetum alopecuroides | Not named | Avoid, limited-evidence. Different fountain grass. USDA states do not include HI |
| Pennisetum genus | Not a Hawaii list | Avoid. USDA states do not include HI |
| Sorghum halepense | Not HISC’s guinea grass | Avoid. US-RIIS invasive-reported for HI and L48. USDA includes HI |
| Arundo donax | Not on HISC’s ten-grass list | Avoid. Same US-RIIS HI flag. USDA includes HI |
Hawaii plant evidence currently holds 227 USDA-distribution records. That is occurrence, not a Hawaii Firewise palette. See when almost nothing is rated.
The opened USGS US-RIIS landing is version 1.0, marked superseded by v2.0. The invasiveIn chips on these rows still store source: us-riis.
The paths
| Question | Opened source | Shortcut that fails |
|---|---|---|
| What is the fuel? | HWMO + HISC: guinea and fountain grass | Planting a continental on-list shrub into the grass |
| Can I landscape with fountain grass? | HISC: do not plant. Noxious weed | Treating Pennisetum alopecuroides as Cenchrus setaceus |
| What do I do in 30 feet? | HWMO Zone One; 5-foot fire-free area; mow to 4 inches | Zone 0 as a Hawaii planting list |
| Is 227 Hawaii records a state list? | USDA distribution | A DLNR Firewise table |
What people mix up
- Chinese fountain grass (P. alopecuroides) with African fountain grass (C. setaceus).
- Johnsongrass with guinea grass.
- A US-RIIS HI flag as a flammability lab.
- HWMO’s 5-foot fire-free area as this site’s Zone 0 rewrite.
- A Nevada greenstrip as a Hawaii greenbreak.
- HISC’s linked Lahaina essay as a quote. That NAISMA page was not opened. This page does not describe Lahaina fuels.
How to check
- Open the HWMO guide PDF. Read the guinea/fountain fire-cycle paragraph and Zone One.
- Open HISC invasive grasses and fountain grass.
- Search this directory for Cenchrus setaceus and Megathyrsus maximus. They are not there.
- Open Sorghum halepense and read the US-RIIS
invasiveInrows. - Open Hawaii plant evidence. Distribution is not a recommendation.
- Do not plant in Zone 0.
Limits
This page quotes the opened HWMO PDF, opened HISC HTML, stored plant records, and the opened US-RIIS v1 landing (superseded). Live hwmo.org HTML returned no usable body. Cenchrus setaceus and Megathyrsus maximus are not in the plant corpus; this page does not invent them. The NAISMA Lahaina article linked from HISC was not opened. Zone 0 is not a planting list.
Related records
- Sorghum halepense
- Arundo donax
- Pennisetum alopecuroides
- Hawaii plant evidence
- What a greenstrip is
- Glossary: Zone 0
- Glossary: defensible space
Questions
Why is the fire-plant question upside-down in Hawaii?
On the continent, the usual question is which shrub to plant. In Hawaii the opened sources start with which grass to stop planting and which grass to remove. Hawaii Wildfire Management Organization’s homeowner guide says invasive guinea and fountain grass ignite easily, re-sprout after fire, outcompete natives, and create a vicious fire cycle. Hawaii Invasive Species Council says wildfire frequency is up 400% over the last century and names fountain grass (Cenchrus setaceus) and guinea grass (Megathyrsus maximus) as high fire hazard, ecosystem-modifying grasses. Fire-resistant here means displacing those fuels, not adding a western Firewise shrub into them.
Does this site have guinea grass or fountain grass pages?
Not for the Hawaii taxa. There is no Cenchrus setaceus record and no Megathyrsus maximus record. Pennisetum alopecuroides is a different fountain grass (Chinese fountain grass); its USDA states array does not include HI. Do not treat that row as Cenchrus setaceus.
What Hawaii grass rows does this directory actually flag?
Sorghum halepense (Johnsongrass) currently computes as avoid and stores US-RIIS invasive-reported for HI and L48. Arundo donax (giant cane) currently computes as avoid with the same US-RIIS HI flag. Those are not guinea grass and not fountain grass.
Did HWMO name a 30-foot zone?
Yes. The opened HWMO guide’s Zone One extends 30 feet from buildings. It also names a fire-free area within 5 feet using non-flammable landscaping and/or high-moisture, drought-resistant vegetation, and says to mow annual grass to a maximum of 4 inches. This site still does not treat Zone 0 as a planting list.
Is this a Hawaii doorway page?
No. The object is the inverted plant question: remove fire-promoting invasive grass, then plant. Place claims sit on whereThisDiffers. The Hawaii plant evidence list is USDA distribution, not this article.