FOUNTAIN GRASS CONTROL IN HAWAII VOLCANOES NATIONAL PARK: MANAGEMENT CONSIDERATIONS AND STRATEGIES
J. Timothy Tunison
excerpted from article in: Stone,
Charles P., Clifford W. Smith, and J. Timothy Tunison. 1992.
Alien plant invasions in native ecosystems of Hawaii:
management and research. pp. 376-393.
ABSTRACT
Fountain grass (Pennisetum setaceum),
perceived as one of the most disruptive alien species in Hawaii.
has threatened native ecosystems below 3,940 ft (1,200 m) elevation
in Hawaii Volcanoes National Park for about 30 years. Because
this species has spread rapidly to high densities on the leeward
side of Hawaii Island, invaded bare lava flows (which results
in disruption of primary succession), has a broad elevational
range (sea level to 6,500 ft [2,000 m] m) elevation), and
has a tendency (to raise fuel loadings, efforts to control this
hardy bunchgrass have been part of the program of resource management
at Hawaii Volcanoes since the early 1960s. In an attempt to increase
efficacy of fountain grass control, data on distribution of the
grass, treatment effectiveness, and work load requirements were
collected beginning in 1979) On the basis or the information obtained
from observations and control attempts, five, management strategies
were proposed in 1986; three of these have since been adopted
to control this threat to Park ecosystems.
INTRODUCTION
Fountain grass (Pennisetum setaceum),
native to Africa, was introduced to Hawaii Island in the Kona
district in the early part of the 20th century. It is now well
established on the leeward side of the Island, with highest densities
in North Kona, North Kohala, and the Pohakuloa area. Scattered
populations occur in windward areas, mostly in roadside habitats.
Fountain grass is readily dispersed by vehicles, humans, wind,
water, and possibly birds.
The species is perceived as one of the most disruptive alien plants in Hawaii (Smith 1985). This large bunchgrass can form monospecific stands, is stimulated by fire, and enhances fuel loadings, thus endangering native woody plant communities it invades. Fountain grass differs from most other nonnative grasses in that it colonizes bare or sparsely vegetated lava flows, thereby disrupting primary succession. It grows in xeric and mesic habitats from sea level to above 8,990 ft (2.740 m) elevation Jacobi, pers. comm.). Potential distribution in Hawaii Volcanoes National Park may include all areas outside closed-canopy rain forest. Therefore, a control program in the Park has also had to address fountain grass distribution in the vicinity of the Park.
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Literature Cited
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