Source: AUBURN UNIVERSITY submitted to
INVASIVE GRASSES IN ALABAMA: STUDIES ON COGONGRASS (IMPERATA CYLINDRICA) RHIZOME ERADICATION AND ARUNDO (ARUNDO DONAX) BIOLOGY ECOLOGY AND CONTROL,
 
PROJECT DIRECTOR: Enloe, S. F.
 
PERFORMING ORGANIZATION
AGRONOMY & SOILS
AUBURN UNIVERSITY
AUBURN,AL 36849
 
NON TECHNICAL SUMMARY: Exotic, invasive grasses constitute one of the greatest threats to the integrity of many natural and agricultural production systems in the United States. Cogongrass (Imperata cylindrica) is an invasive rhizomatous grass species that currently infests thousands of acres in south Alabama and is rapidly spreading northward. Cogongrass is a pyrogenic species that is very destructive in natural areas, pastures, and forestry plantations. Arundo (Arundo donax) is also a creeping perennial grass up to 10 m tall that is highly invasive from South Texas to California. It forms dense stands in riparian areas and reduces native biodiversity and increases fire hazards. There is increasing interest in its use as a biofuel crop in Alabama and large scale Arundo biofuel plantations may soon be developed. Currently, Arundo has escaped from ornamental plantings and is found in small clonal patches throughout Alabama. However, its distribution, mechanisms of spread, ecosystem impacts, and susceptibility to management in Alabama are largely unknown. Current Alabama noxious weed laws are not effective in dealing with these species. Cogongrass is currently regulated; however, there is a lack of coordination for dealing with it on a statewide basis and thus it continues to spread. Furthermore, eradication of cogongrass has rarely been pursued to completion from a research perspective. Most studies have found methods that provide short term control, but few have been carried out to the point of complete eradication (i.e., elimination of all cogongrass reproductive propagules such as seeds and rhizomes). To successfully stop the continued spread of cogongrass in Alabama, it is imperative that we determine the strategies required for complete eradication. Arundo is a highly controversial species due to its potential as a biofuel crop that could be economically important to Alabama. The issue is currently polarized between two prevailing camps (biological conservation versus economic development). However, both groups lack data relevant to Alabama ecosystems on the Arundo invasive issue. This research will provide clarification on the issue of invasiveness and will put the Alabama AES at the forefront of the issue.
 
OBJECTIVES: Exotic, invasive grasses constitute one of the greatest threats to the integrity of many natural and agricultural production systems in the United States. Cogongrass (Imperata cylindrica) is an invasive rhizomatous grass species that currently infests thousands of acres in south Alabama and is rapidly spreading northward. Cogongrass is a pyrogenic species that is very destructive in natural areas, pastures, and forestry plantations. Arundo (Arundo donax) is also a creeping perennial grass up to 10 m tall that is highly invasive from South Texas to California. It forms dense stands in riparian areas and reduces native biodiversity and increases fire hazards. There is increasing interest in its use as a biofuel crop in Alabama and large scale Arundo biofuel plantations may soon be developed. Currently, Arundo has escaped from ornamental plantings and is found in small clonal patches throughout Alabama. However, its distribution, mechanisms of spread, ecosystem impacts, and susceptibility to management in Alabama are largely unknown. Current Alabama noxious weed laws are not effective in dealing with these species. Cogongrass is currently regulated; however, there is a lack of coordination for dealing with it on a statewide basis and thus it continues to spread. Furthermore, eradication of cogongrass has rarely been pursued to completion from a research perspective. Most studies have found methods that provide short term control, but few have been carried out to the point of complete eradication (i.e., elimination of all cogongrass reproductive propagules such as seeds and rhizomes). To successfully stop the continued spread of cogongrass in Alabama, it is imperative that we determine the strategies required for complete eradication. Arundo is a highly controversial species due to its potential as a biofuel crop that could be economically important to Alabama. This research will provide clarification on the issue of invasiveness and will put the Alabama AES at the forefront of the issue. 1)Determine the sequential number of treatments and timings necessary for complete elimination of cogongrass rhizomes. 2)Implement statewide educational efforts to increase awareness and detection of cogongrass to stop its northward spread. 3)Create a statewide distribution map of Arundo donax to ascertain this species current extent in Alabama. 4)Determine Arundo mechanisms of spread and ecosystem impacts. 5)Determine effective Arundo eradication methods 6)Develop and implement educational programming based upon our research findings. Based upon our research findings, we will implement education and outreach programs on both species as the project moves forward. Methods of dissemination will include online facts sheets and videos, local meetings in communities around Alabama, and larger statewide (Alabama Vegetation Management Society, Alabama Invasive Plant Council) and southeast regional meetings (Southern Weed Science Society and Southeast Exotic Pest Plant Council.
 
APPROACH: We will initiate field studies at multiple locations in southern Alabama. Studies will be RCB designs with four replications per treatment. Plot size will be 10 by 10 m with 3 m buffers around all plots. Buffers will be kept free of cogongrass with a combination of tillage and glyphosate applications to prevent rhizome encroachment into the plots. The buffers are a critical component that few researchers have previously used and will allow us to follow the plots for several years. The treatment structure will consist of varying glyphosate and imazapyr rates and sequential timings. The sequential treatment timings will be based upon the cogongrass response to initial treatment. To determine optimal sequential timings, we will utilize a destructive sampling approach and destructive harvesting techniques within plots to quantify rhizome biomass, bud release and elongation and total nonstructural carbohydrate (TNC) levels. This will allow us to determine treatment impacts on cogongrass rhizomes and apply sequential treatments in a manner that prevents recovery and maintains a negative trajectory in terms of rhizome energy reserves. These studies will be continued for 3-4 years or longer if necessary to determine the treatment sequences necessary for complete cogongrass rhizome eradication. Arundo Studies Mapping Studies: A multistep approach will be used to map naturalized Arundo donax populations in Alabama. The first step will be an exploratory survey of the State. Exploratory surveys are useful to cover large areas at low cost. The outcome is a general distribution map of Arundo populations using point data. To initiate the survey and prioritize state regions, we will utilize multiple existing resources within the state and region including the Early Detection and distribution Mapping System (http://www.se-eppc.org/eddMapS/distribution.cfm), Alabama Cooperative Extension System, NRCS, Alabama Department of Transportation, and other State and Federal agencies. The second step will then focus mapping efforts to verify reports and establish GPS points of Arundo locations across the state. At each Arundo site, initial data will be collected to begin to make generalizations concerning Arundo naturalization. These will include visual estimated patch size and height, estimated proximity to garden or flowerbed plantings, estimated linear distance to roads, estimated linear distance to standing/flowing water, presence/absence of mowing, presence/absence of fill dirt in relation to the location, presence/absence of recent or ongoing disturbance near or within the stand such as construction or wildlife disturbance, evidence of recent fire within or around stands, and several others. Arundo spread and impact studies: Based upon our exploratory mapping, we will select a subset of Arundo populations for intensive sampling. We will quantify a number of important characteristics including patch size and density, annual clonal rates of spread, biotic and abiotic conditions within and around Arundo stands and local community impacts.
 
CRIS NUMBER: 0216078 SUBFILE: CRIS
PROJECT NUMBER: ALA012-1-08028 SPONSOR AGENCY: NIFA
PROJECT TYPE: HATCH PROJECT STATUS: NEW MULTI-STATE PROJECT NUMBER: (N/A)
START DATE: Oct 1, 2008 TERMINATION DATE: Sep 30, 2013

GRANT PROGRAM: (N/A)
GRANT PROGRAM AREA: (N/A)

CLASSIFICATION
Knowledge Area (KA)Subject (S)Science (F)Objective (G)Percent
136230011406.320%
213242011404.280%

CLASSIFICATION HEADINGS
KA213 - Weeds Affecting Plants
KA136 - Conservation of Biological Diversity
S2420 - Noncrop plant research
S2300 - Weeds
F1140 - Weed science
G4.2 - Reduce Number and Severity of Pest and Disease Outbreaks
G6.3 - Protect and Manage Forests and Rangelands


RESEARCH EFFORT CATEGORIES
BASIC 20%
APPLIED 70%
DEVELOPMENTAL 10%

KEYWORDS: cogongrass, arundo, giant reed, eradication, invasive grasses

PROGRESS: Jan 1, 2010 TO Dec 31, 2010
OUTPUTS: For our cogongrass eradication study, in 2010, the third consecutive year of herbicide eradication treatments were applied to plots at both resesearch sites in Mobile and Bayou La Batre, Alabama. Cogongrass cover and rhizome and shoot biomass were measured in the spring, summer and fall in each treated plot. Rhizome samples were also collected in each season for total non structural carbohydrate analysis. Additionally plant cover of all other species was measured during the summer. While data collection is still ongoing, results have been disseminated in over 10 venues throughout Alabama, including cogongrass and invasive plant workshops, the Alabama Vegetation Management Society Annual conference, the Southeast Exotic Pest Plant Council Conference, Alabama Cattlemen's meeting, and several forestry meetings. PARTICIPANTS: Ongoing partners in this project include the Alabama Forestry Commission, Alabama Cooperative Extension System, The Alabama Agricultural Experiment Station, Natural Resource Conservation Service and multiple Resource Conservation Districts in Alabama. TARGET AUDIENCES: Target audiences have included private landowners, forestry consultants, farmers, hay producers, agency personnel, and rights of way managers. PROJECT MODIFICATIONS: The only major changes is a lack of additional research on Arundo donax. Funding has not been acquired to research Arundo as of yet.

IMPACT: 2010-01-01 TO 2010-12-31 The results of this research have been implemented in the treatment of over 2,300 patches of cogongrass in Alabama through the Alabama Cogongrass Control Program. Additionally, we have educated hundreds of landowners who are actively managing their own cogongrass problems. This is also an ongoing effort which is part of a larger regional effort to stop the spread of cogongrass in the Southeastern United States.

PUBLICATION INFORMATION: 2010-01-01 TO 2010-12-31
No publications reported this period

PROJECT CONTACT INFORMATION
NAME: Liu, J.
PHONE: 334-844-8727
FAX: 334-844-2937