Narrow-leaved and Hybrid Cattail MC

Species Management and Control Information

Narrow-leaved and Hybrid Cattail
Typha angustifolia and T. x glauca

SOURCE: The following information is taken from a number of sources and those sources are identified at the beginning of the referenced information. The intent of this resource is to provide the user with as much of the information that exists for management and control of this species as is practical. It is important to note that new and improved methods are added regularly which will require you to visit the websites provided for updates on this information. Bibliographies and resources referenced by these sources are not included here, but are included at the websites from which this information was extracted.

READ THIS FIRST!

Before administering any of the following management and control options, it is imperative that you are familiar with the background information provided under the General Management and Control Section.

For additional, and potentially more current, information on management and control of this species, use the Mid-Atlantic Exotic Pest Plant Council (MA-EPPC) listserve or any of the other listserves identified in the Resource - Listserve section of this tutorial. You will find directions for subscribing to the list serve there. The MA-EPPC listserve has an archives feature that saves past discussions (beginning in 1999) about specific species control. These messages are at: http://groups.yahoo.com/group/ma-eppc/messages.

GENERAL MANAGEMENT CONSIDERATIONS:

Wisconsin Department of Natural Resources - Non-Native Plants Fact Sheets - Common cattail and Narrow-leaved cattail - http://www.dnr.state.wi.us/org/land/er/invasive/factsheets/cattail.htm

The acreage of cattail-dominated wetlands in the United States has increased drastically since the early twentieth century due to changes in hydrology and land use. The optimal control technique for a given site will depend on the hydrologic state of the site, the size of the area to be managed, and if the manager is able to manipulate water levels.

MANUAL AND MECHANICAL CONTROL:

Ohio Department of Natural Resources - Division of Natural Areas and Preserves - Invasive Plants of Ohio Fact Sheet #11 - Narrow-leaved and Hybrid Cattail - http://www.dnr.state.oh.us/dnap/invasive/11cattail.htm - January 8, 2003.

Manipulation of water levels can kill cattails by inhibiting airflow from the cattail shoots to the roots. Removing the dead leaves and submerging the shoots in early spring will eliminate gas diffusion and "suffocate" the plant. In situations where water level manipulations are either not feasible or appropriate, pulling, cutting and bulldozing treatments have been used with some success. In the case of bulldozing, the benefits in effective removal may not outweigh the costs of disturbing the wetland.

The Nature Conservancy - Invasive Species Initiative - Species Management Summary (ESA or Element Stewardship Abstract): Typha spp. - http://tncweeds.ucdavis.edu/esadocs/typh_spp.html - Author: K. Motivans and S. Apfelbaum - October 27, 1987.

WATER LEVEL MODIFICATION:
High water conditions in a cattail stand can affect the growth of seedlings, can break off mature stalks, or can be followed by the immigration of muskrats which eat the cattail (Zimmerman pers. comm.). The effect of flooding does not always have negative impacts on cattails -- plants have been known to float up and continue growing until water returns to a previous lower levels.

As with any control measure, temporary conditions, such as flooding, do not prevent later seed establishment. Cattail seeds can arrive from a great distance, and it doesn't take but a few seeds to germinate and rapidly produce clones as adults. The cost of management actions should be considered when dealing with unknown response variables.

Low water conditions, maintained by draining a wetland, significantly effects the overall community (Mallik and Wein 1985). Harris and Marshall (1963) concluded that draining techniques have possible detrimental effects because the plant composition of a wetland can be radically changed. Draining alone can cause a significant increase in Typha cover under some conditions (Mallik and Wein 1985). However, to inhibit Typha growth, a wetland can be drained and then burned during the summer. If there is no reserve of water over winter cattails will not survive the following spring, according to Zimmerman (pers. comm.) but there have been no controlled experiments to show this.

Two years of 65 cm (26 in) deep flooding was required before established cattail began to die and open water conditions were created at Sinnissippi Marsh. Cattail initially survived flooding from 1973-1977 and became the dominant emergent plant. A light green color, noticeably narrower leaves, and absence of fruiting heads indicated stress in 1976. Cattail stem densities declined 57 percent with all emergent plants dead in 1977. Horicon Marsh, flooded to a depth of 40 cm (16 in), showed declines in emergent and aquatic plants. Cattail required two years before it declined (Wisconsin DNR 1969 and 1971).

Mature T. latifolia and seedlings less than one year old are killed by water depths of 63.5 cm (25 in) and 45 cm (18 in) or more, respectively. Narrow-leaved cattail was unaffected by this degree of flooding. Narrow-leaved cattail establishment was prevented when water levels were maintained at 1.2 m (47 in) or deeper (Steenis et al. 1958). Dryer conditions allowed more clones of T. angustifolia to be spread (McMillan 1959).

Because cattails can transpire significant quantities of water (2-3m of water/acre/year) (Fletcher and Elmendor 1955, Zohary 1962), their establishment may serve to exacerbate water level instability and further contribute to disruptive influences supporting increased cattail. Flooding must account for evapotranspirational losses of water to maintain a level effective in cattail control.

PHYSICAL CONTROL:
Hand or mechanical cutting of cattails followed by submergence of all cattail stems results in high control. Up to 100 percent cattail control was measured two growing seasons after treatment. No visible cattail regrowth occurred in one year and cattail rhizomes were dead. The highest cattail control of any method tested was achieved by two clippings followed by stem submergence to at least 7.5 cm (3 in) (Nelson and Dietz 1966). Control was best if plants were cut in late summer or early fall.

In Iowa (Weller 1975), cutting cattail and reflooding with at least 8 cm (3.1 in) of standing water over plant stems was effective. Weller (1975) also found clipping cattails too early in the growing season (e.g. May) stimulated their growth and resulted in a 25 percent increase in stem counts the following year, with an eventual decline to preclip levels. August clipping controlled up to 80 percent of cattail only if followed by submergence. It was important to remove all dead and live cattail stems to achieve this control. Cutting shoots below the water surface two or three times in one growing season before flower production reduced a cattail stand by 95-99 percent in Montana and Utah (Stodola 1967). Similar results were demonstrated by Shekhov (1974) and Sale and Wetzel (1983).

When shoots are cut below the water level, nearly all the oxygen is consumed in a short time, necessitating anaerobic respiration. In Typha, ethanol is produced accompanied by tissue breakdown after an oxygen shortage. Typha is ill adapted to deprivation of oxygen. Cuttings later than flowering stage are effective only in preventing regrowth for that year and may have no effect on subsequent years (Shekhov 1974).

Cattail control by injuring developing rhizomes and shoots was investigated (Weller 1975). Crushing and reflooding showed that cattails injured after June had poor recoveries. Success of crushing depended on the load used, number of times an area was crushed, and standing water depths after treatment. Spring and early summer treatments generally created favorable seedbeds for cattail and required a fall crushing to control seedlings. Crushing involved pulling a 55 gallon water filled drum behind a tractor. Deeper water areas showed highest control (up to 100 percent) while regrowth occurred in shallow areas. Although not practical for natural areas management, discing (Weller 1975) and blasting (Nelson and Dietz 1966) have also been investigated as methods of cattail control.

SHADING:
Black polyethylene tarps were used to cover cattails in an attempted control measure (Nelson and Dietz 1966). Actively growing cattail tips were killed when completely covered for at least sixty days. Greatest control was achieved in July when food resources of cattail were presumed to be lowest (Linde et al. 1976). Problems with holding tarps down and their degradation confounded this investigation. Cattail is generally not shade tolerant.

Wisconsin Department of Natural Resources - Non- Native Plants Fact Sheets - Common cattail and Narrow-leaved cattail - http://www.dnr.state.wi.us/org/land/er/invasive/factsheets/cattail.htm

Water Level: The control of cattails by the manipulation of water level must be timed to the annual cycle of carbohydrate storage. Special leaf and stem cells called aerenchyma provide air passage from both living and dead leaves to the rhizomes. Removing dead leaves and submerging the shoots in early spring will strain the plant and eventually kill it. The depth of water necessary to kill the plants depends on temperature, the quantity of starch the plant stored the previous year, and the general vigor of the plants. Therefore, no minimum water depth can be prescribed, but, generally, a water level maintained at 3-4 feet above the tops of existing spring shoots will retard growth. It is critical to remember that even if dead leaves from the previous year are completely removed, aerobic conditions will be restored to the rhizome as soon as the new growing shoot penetrates the water surface. Even if water levels are sustained at only a few inches above the tops of the growing shoots, oxygen is prevented from reaching the rhizomes. The use of water is most efficient if the water level is raised progressively, so that all plant parts remain submerged by no more than a few inches. Water levels in the range of four to five feet also favor the wintertime survival of muskrats in flooded areas. Population levels of ten muskrats per acre, when combined with high springtime water levels, can nearly eliminate the emergence of cattails within a span of two years.

Cutting, Crushing, Shearing, and Discing: Starch reserves in the rhizomes are at their minimum in late spring when the pistillate spike of the cattail is lime green and the staminate spike is dark green. This is the best time to employ cutting, crushing, shearing, and/or discing to eliminate cattail colonies because all these methods impede starch storage during the growing season. The methods of control work best if employed during a three-week time window beginning one week before and ending one week after the staminate spike has emerged. Deep discing can retard shoot formation and damage the rhizomes, but should be used in combination with water-level control and the prevention of seed establishment to effectively hinder the re-emergence of cattails. Discing combined with continued drying and freezing in fall decreases plant survival; if a wetland can be kept dry enough to repetitively disk for 2-3 successive seasons, cattails can be eliminated or their stem densities severely reduced. However, discing has some major drawbacks: the equipment and personnel needed to carry out this method of control are costly, and will seriously disturb the site. This will likely result in the loss of other native plants in the area as well.

Cutting, crushing, shearing, or discing severs the aerenchyma link that provides oxygen between the rhizomes and leaves of cattails during dormancy. These techniques must be combined with high springtime water levels in order to effectively retard plant growth. Cattails can be cut with a rotary mower or sheared with a front-end loader on a tractor when equipment can be driven on ice, but airborne seeds may clog equipment. High water levels must be maintained throughout the spring and early summer.

Bulldozer: Bulldozers can effectively remove plants from a marsh, but will generally drastically disturb the wetland. Permits must be obtained before clearing a marsh with heavy equipment. A bulldozer or or other machinery is the only viable method that will remove floating cattail mats, but these removal methods are also costly, and effects may be short-lived. If the seed bank of the marsh is dominated by cattails, a new colony of the hardy plants may spring up after the next drawdown of the marsh; other undesirable plants could also take the place of the cattails in the marsh.

GRAZING:

Wisconsin Department of Natural Resources - Non-Native Plants Fact Sheets - Common cattail and Narrow-leaved cattail, http://www.dnr.state.wi.us/org/land/er/invasive/factsheets/cattail.htm

Grazing by cows, geese, muskrats, and other animals can be an effective method of cattail management. Grazing on seedlings and young cattails without extensive rhizomes can reduce the stem density of the colony. For mature plants, grazing combined with water-level management reduces survival rates. To maximize the impact of grazing, it should be heaviest during the three-week window of time when the flower spikes are emerging.

PRESCRIBED FIRE:

Fire alone was found to provide little or no cattail control (Nelson and Dietz 1966). Fires that destroyed cattail roots offered control; however, most fires only burned above-ground biomass and did little to control cattail. Drying in readiness for burning was effective cattail control when done for two years in arid Utah. Water was pumped from wetlands and then cattail stands were allowed to sun dry.

Water level drawdown, burning (Spring, Fall, and mid-growing season), and reflooding to 20-35 cm (8-18 in) water depth or deeper controlled cattail. Fire was found useful for cattail litter cleanup and assisted access for mowing or hand clipping (Nelson and Dietz 1966, Weller 1975, Mallik and Wein 1985).

Wisconsin Department of Natural Resources, Non-Native Plants Fact Sheets, Common cattail and Narrow-leaved cattail, http://www.dnr.state.wi.us/org/land/er/invasive/factsheets/cattail.htm

Most cattail marshes must be burned in winter or before significant growth has occurred in spring; these are generally the only times when fuels are dry enough to carry a fire, although frozen ground or saturated soil may impede the fire's progress through the cattail duff. Fire is most effective as a control method when followed by naturally or artificially high water levels in the spring to smother residual stalks.

During times of drought, cattail stands overlying well-developed peat soils can be eliminated by burning. Because such fires burn peat, the ability to smother the fire by reflooding the marsh must exist before a prescribed burn can be implemented. Peat fires can also cause undesirable changes in the marsh environment, such as destruction of the seed bank, loss of peat, and air pollution.

BIOCONTROL:

Currently there are no biological control methods for cattails.

CHEMICAL CONTROL*:

Wick and foliar applications of systemic herbicides such as Accord®, Rodeo® or Glypro® followed by manual clipping and removal of stems can be successful. Re-treatments are usually necessary due to the extensive root system.

The Nature Conservancy - Invasive Species Initiative - Species Management Summary (ESA or Element Stewardship Abstract): Alliaria petiolata - http://tncweeds.ucdavis.edu/esadocs/allipeti.html - Author: Victoria Nuzzo - February 2000.

For designated preserves or natural areas, especially where system-orientated stewardship is used, chemical applications may not be appropriate. This is particularly true because cattail is an element of certain natural communities. However, use of chemicals to control an overabundance of cattail may have certain applications. Spraying Dalpan (Nelson and Dietz 1966) at 8.8-35.3 kg/acre (4-16 lb/acre) produced 74-97 percent reductions in cattails ten months after a mowed area was sprayed. Cattail regrowth was sprayed at 58-90 cm (24-36 in) height in September. Control was most effective when treated areas could be flooded to 10-15 cm (4-5 in) or deeper. Dalpan spray achieved varied success but greatest control occurred where cattail stems were cut below water depths regardless of the herbicide quantity used. Poorest results were attained in areas with shallow fluctuating water levels. Spraying mature cattails rather than regrowth after cutting gave better results. Weller (1975) had similar results with spraying where Amitrol, Rodopan, and Douupon herbicides were effective in creating and maintaining openings for at least three years after spraying, but areas were quickly invaded by peripheral cattail. High doses of MCPA or 2,4-D in diesel oil (2.2-4.5 kg per acre) were effective if applied during flowering. Dalpan (9 kg/acre) and Amino-triazole (.91-1.36 kg/acre) gave good control results in Montana (Timmons et al. 1963). Herbicide applications were found necessary for up to three years in some areas. Similar results were found by Grigsby et al. (1955), Heath and Lewis (1957), Krolikowska (1976), Pahuja et al. (1980), Singh and Moolani (1973), and Wisconsin Department of Natural Resources (1969).

Wick and spray applications of Roundup followed by manual clipping of all cattail stems was the treatment conducted by Applied Ecological Services and All Services Company (1985) at a pond in northern Illinois. Cattail seeds were just at ripening stage at the time of treatment. Retreatment of Roundup several weeks later and subsequent die-off proved this method successful.

Herbicide treatment at flowering may stress the cattail plants more than at other stages since the energy investment by the plant has been channeled into flowering.

Wisconsin Department of Natural Resources - Non-Native Plants Fact Sheets - Common cattail and Narrow-leaved cattail - http://www.dnr.state.wi.us/org/land/er/invasive/factsheets/cattail.htm

Application in mid to late summer enhances the effectiveness of translocated herbicides, although the herbicides will have little effect on seed production during the year of application. A hemi-marsh may be created if some cattails survive, although the ability of the marsh to persist in this condition depends on the manipulation of water levels. Water level control to minimize recruitment from the seed bank must be used to ensure cattails will not return once reduced by herbicides.

Herbicides can be detrimental to wetlands habitats--be sure to use herbicides that readily break down in water, soil, or substrate, such as glyphosate formulated for use over water. Boom or wick applications by ground or air boat are best for small areas where pesticide drift is a concern. Aerial applications may be used on large areas. Herbicidal control of cattails may be costly, although actual application of the herbicide usually represents a small fraction of this cost. One area manager found that an aerial application of glyphosate during August was effective in controlling cattails, dogwood, and willow, but quite costly at $110/acre. Due to the possibility of fish contamination, notice must be posted before spraying, and can be done only by a person licensed to apply herbicides.

* Mention of pesticide products in this document does not constitute endorsement of any particular material.