plantations have been established on over 20,000 acres of former
sugar cane lands in East Hawaii. A major problem in plantation establishment
has been weed control, especially of guinea grass (Panicum maximum).
The grass competes with the trees for moisture and nutrients, probably
decreasing growth of the trees. Thick grass under trees also is
also fuel and increases the risk of fires in the forest plantations.
Guinea grass persists even under closed canopy forests in some areas.
Currently forestry companies manage the grass with repeated applications
of herbicides, which adds to management costs. Herbicide application
also sometimes causes friction with neighboring farmers and residents.
At the same time, the
cattle industry is seeking additional grazing lands to increase
local production of forage-fed beef. Currently most cattle are shipped
out of Hawaii for raising on the mainland. Efforts are underway
to develop feedlots for finishing Hawaii-grown grass-fed beef. The
missing link is pasture lands to raise stocker cattle. If cattle
can be successfully grazed under tree plantations, a large forage
resource will become available which will create new opportunities
for Hawaii-raised livestock.
and External Linkages
CTAHR: Cooperative Extension Service; Human, Food, and Animal Science;
Natural Resource and Environmental Management
Private: Robert Sporleder, BETC Technologies; Forest Solutions,
forest plantation managers, landowners; CES Cooperative Extension
faculty and other natural resources agency staff, including NRCS
and DOFAW staff; private consultants.
Demonstrate grazing of cattle under forest plantations as a means
of weed control for forestry and a means of providing additional
high-quality forage to the beef industry.
Plan of Work
1. Establish field site. Cooperate with Forest Solutions, a private
consulting company, to select field site on land leased by PruTimber
from Kamehameha Schools and currently planted with Eucalyptus grandis.
2. Design replicated trials with varied treatments (heavy graze,
3. Fence area.
4. Establish sub-plots for forestry measurements (50 trees each)
and measure trees (diameter and height).
5. Fence area.
6. Graze cattle.
7. Conduct field day while cattle are grazing. Invite people from
8. Re-measure trees.
9. Write report, extension leaflet, and website on project. (Models:
CTAHR extension leaflets; CTAHR forestry extension website, CTAHR
Outputs: Hold field day with at least
5 natural resources extension professionals and 10 private landowners
Produce extension leaflet and distribute to at least 50 landowners.
Produce extension website.
Cattle grazed under forest plantations on at least 500 acres.
Weed control costs decreased on areas grazed (500 acres).
Tree growth improved on areas grazed because of reduced weed competition.