Ames Plantation

Japangrass Control Evaluations

Japangrass Control Evaluation

With the aid of staff members from The University of Tennessee's Departments of Plant and Soil Science and Botany, a particularly undesirable grass which sprung up on many areas of the Ames Plantation the last 2 years has been identified as Japangrass (Microstegium vimineum). An acceptable, effective control measure which can be safely implemented in a field trial environment is now being sought.

Following consultation with several knowledgeable weed scientists, the following tests have been installed (main cooperators are identified):

American Cyanamid (Dr. Joe Vollmer and Todd Horton) and Quail Unlimited (Mike Hansbrough):

3 rates of Plateau (American Cyanamid) herbicide + Solar (a methylated seed oil adjuvant)

1 rate of Plateau herbicide + Pendulum (American Cyanamid) herbicide + Solar

The University of Tennessee Agricultural Experiment Station - Plant and Soil Science Department (Dr. Bob Hayes):

2 rates of Roundup Ultra (Monsanto) herbicide

1 rate of Select (Valent) herbicide + Agridex

1 rate of Accent (Du Pont) herbicide + Agridex

1 rate of Fusion (Zeneca) herbicide + Agridex

1 rate of Pursuit (American Cyanamid) herbicide + Agridex

1 rate of Sencor 75DF (Bayer) herbicide + X-77

1 rate of Authority (FMC) herbicide + X-77

Ames Plantation Experiment Station (Drs. Allan Houston and R. J. Carlisle):

3 rates of Oust (Du Pont) herbicide

1 rate of Arsenal (American Cyanamid) herbicide + Oust herbicide

1 rate of Velpar (Du Pont) herbicide

2 rates of Fusilade (Zeneca) herbicide + crop oil

1 rate of Fusilade herbicide + Pendulum herbicide + crop oil

During the first two weeks after the installation of these plots, evaluations of herbicide impact on Japangrass and desired grasses and legumes were completed by Ames Personnel. Based on these admittedly short time frames, the following combinations were selected for large acreage applications on the two field trial courses:

Authority herbicide - from Dr. Bob Hayes' plots (apparent kill of Japangrass with good emergence of sedge grass as well as desirable legumes such as partridge pea and Kobe lespedeza)
Select herbicide - from Dr. Bob Hayes' plots (post treatment results similar to Authority)
Plateau herbicide - from plots installed by Dr. Joe Vollmer and Todd Horton (superb kill of Japangrass, substantial control of broadleaf weeds, excellent emergence of sedge grass, and good emergence of desirable legumes when applied at the lowest rate)

Reference is made to the above summary of observations over the first 2 weeks following application of several products to control Japangrass while allowing for emergence of desirable plants. Further evaluations at about 2 months post treatment resulted in the following conclusions:

Authority, Select, and Plateau herbicides all did an acceptable job of controlling Japangrass infestations under the hot, dry conditions experienced on Ames Plantation during May and June, 1998. Overall subjective evaluations of Japangrass control support the earlier conclusion that Plateau, if available, at 4-5 ounces of active ingredient per acre is the product of choice for controlling Japangrass in wildlife environments where ground nesting birds are a high priority. Plateau, at these relatively low rates, controls Japangrass which reduces rodent habitat quality while allowing for the emergence of plant communities and subsequent development of ground conditions which are particularly suitable for bobwhite quail reproductive efforts.
Authority resulted in some early control of Japangrass but the Japangrass is recovering and growing vigorously.
Select herbicide did not result in death of the plant. Consequently, on May 27 Japangrass is once again establishing itself in the plant community.
Plateau herbicide applied at 4 ounces active ingredient per acre gave excellent control of Japangrass through the first month of evaluation. Plateau herbicide resulted in a clean ground environment with sedge grass and partridge pea clearly noticeable.
Japangrass stems range from 75 to 100 per square inch when no control measures are exerted.

As of June 12, 1998, 436 acres of heavily infested Japangrass areas (256 acres on the morning field trial course and 190 acres on the afternoon course) have been treated with one of the above three products. Evaluations in early July indicated no need for spraying Japangrass infestations previously treated with Select, Authority, or Plateau.

In 1999, the control effort continues.

Our experience at Ames Plantation plus reports from New York state, Pennsylvania, Maryland, Cherokee National Forest in East Tennessee, personal observations in the Great Smoky Mountains National Park, and from as far away as Thailand all suggest that Japangrass will need intense efforts to control in many environments. Our evaluations of methods will continue in 1999. Watch this site for updates.