Giant cane (Arundinaria gigantea (Walter) Muhl.), a native species of bamboo, occurs in communities scattered across much of the southeastern and lower midwestern United States.  Native cane is functionally important in the Southeast as it preserves water quality and serves as essential habitat type that many biotic species depend upon for their survival. However, comparison of present distribution with historical accounts indicates a significant loss of cane in the landscape.  Cane previously grew in expansive stands, known as canebrakes, which most commonly spanned floodplains. However, the species also occurred on upland slopes, bluffs, and ridges.  Agriculture, land clearing, and altered fire regimes however have caused cane to become isolated in sporadic communities primarily along riparian corridors.  Thus, canebrakes are now considered as critically endangered ecosystems (Noss et al. 1995). 

The exclusion of fire from cane stands reduces aboveground stem (culm) density and overall health (Hughes 1966).  Yet with proper fire management existing canebrakes can thrive in much of the Southeast.  Researchers have shown that 10 year burn intervals can maximize the productivity of cane stands (Hughes 1966). During the 5^th growing season following a burn however, fuel loads are near their peak (~7 tons per acre).  Therefore shorter burning cycles may be used if maintaining fuel loads in canebrakes is a primary management objective (Hughes 1966). 

In the Southeast, canebrakes generally are not managed using prescribed burns because of the difficulty in controlling the burns and the potential associated fauna loss.  Because of isolation, burning a canebrake could threaten the future of biota dependent on cane as a food source and/or habitat.  However, through the implementation of proper conservation and restoration methods, such as overstory tree removal and prescribed burning where only one third of the area is burned in any year and allowed to recover before the adjacent area is burned, there is high probability that this unique community of the Southeast can be maintaned.

Farrelly (1984) documented that Giant cane can grow under an array of environmental conditions, ranging from sea level in the Coastal Plain regions to 670 meters in the Appalachian Mountains and across a diverse suite of soil conditions from highly acidic to sandy.  A map of the distribution of canebrakes in the southeastern U.S. is available at the USDA Plants Database.  Presently canebrakes are largely confined to bottomlands along the Mississippi Delta, swamplands of Virginia, North Carolina, and in the Ocmulgee Basin in Georgia (Meanley 1972; Platt and Brantley 1997).

Giant Cane

Associated Species

Cane is an important component of many deciduous and evergreen forests.  It has been associated with Carolina bays, pocosins, pine barrens, upland forests, bottomland hardwood forests, and swamp forests (Platt and Brantley 1997).  Canebrakes have also been documented to grow with several different associated species.  In eastern North Carolina, Hughes (1966) found that pond pine (Pinus serotina) was the chief overstory associated with cane.  Walkup (1991) lists several overstory species with cane including: red maple (Acer rubrum), loblolly-bay (Gordonia lasianthus), Ohio buckeye (Aesculus glabra), honey locust (Gleditsia triacanthos), Kentucky coffee tree (Gymnocladus dioicus), and pawpaw (Asminina triloba).  Understory species included laurel greenbrier (Smilax laurifolia), inkberry (Ilex glabra), large gallberry (I. coriacea), zenobia (Zenobia pulverulenta), swamp cyrilla (Cyrilla racemiflora), southern waxmyrtle (Myrica cerifera), sweet pepperbush (Clethra alnifolia), and saw-palmetto (Serenoa repens). Schoonover and Williard (2003) noted trumpet creeper (Campsis radicans) and poison ivy (Toxicodendron radicans) as common understory species in a southern Illinois canebrake.

In the Coastal Plain of the Southeast, canebrakes are an early successional sere, a transition between savannahs and other wetlands such as pocosins, bay forests, and swamp forests (Wells and Whitford 1976).  Depending upon the variability of fire frequency and the flood regime, canebrake communities may alternate with these other community types.  Further, canebrakes are often natural ecotones between wetland communities and upland forests.  Intense annual burning of swamp forests generally produces savannahs whereas cane and shrub pocosins are produced from less frequent burn regimes (Wells and Whitford 1976).  In the absence of fire, canebrakes will eventually succeed to bay or swamp forest (Wells and Whitford 1976)

Canebrake ecology and management has been largely ignored by many researchers in the U.S.  Yet this community type has significant ecological importance.  Some individuals have proven canebrakes to be crucial nesting habitats for birds (Meanley 1966; Remsen 1986; Hamel et al. 2001) and others have shown the importance of riparian cane in protecting stream water quality (Schoonover et al. 2002,  2004a, 2004b, Schoonover and Williard 2003). 

Biota Associated with Canebrakes

Platt et al. 2001 did an extensive literature review on the biota that utilizes canebrakes as part of their habitat or food source.  They reported 50 species that have been documented in canebrakes, including 23 mammals, 16 birds, 4 reptiles, and 7 invertebrates.  The documented species are summarized in the table Canebrake biota, which was adapted from Platt et al. 2001.

Swamp Rabbit

Swamp rabbits (Sylvilagus aquaticus) inhabit poorly drained river bottoms and coastal marshes.  Along the coast, swamp rabbits are at home in cane thickets and thus have inherited the name “cane cutter” and/or “cane jake” (Lowery 1974; Davis and Schmidly 1997).  According to the Georgia Wildlife Web Site, swamp rabbits in Georgia thrive on eating cane shoots. 

Black Bears

Many of the southeastern states that have populations of black bears (Ursus americanus) see cane as a valuable habitat and forage.  The Black Bear Conservation Committee (1992) regarded canebrake habitat restoration as a high priority for the protection of Louisiana black bears. 

Bachman’s and Swainson’s Warbler

Both Swainson’s warbler (Limnothlypis swainsonii) and Bachman’s warbler (Vermivora bachmanii) habitat descriptions often include canebrakes as a critically important component (Meanley 1966; Hamel 2001).  Bachman’s warbler, now probably extinct, was likely a bamboo specialist in that it required dense canebrakes for nesting (Remsen 1986).  Virtually every detailed nesting account of this bird mentioned cane, and the vast decline of canebrakes was likely instrumental in the virtual disappearance of this bird (Remsen 1986).  The Swainson’s warbler is today a relatively uncommon migrant.  Swainson’s warbler is generally associated with dense thickets of cane and declines have been attributed to habitat loss on both wintering and breeding grounds (Somershoe et al. 2003).  Other birds that are associated with Swainson’s warbler and cane in general (although not as habitat specific as Swainson’s warbler) include Cardinal (Richmondena cardinalis), Hooded warbler (Wilsonia citrina) and the White-eyed vireo (Vireo griseus) (Meanley 1966). 

Lepidoptera larvae

A large number of lepidoptera are suspected to exclusively feed on cane as larvae (Table: Canebrake biota).  As adults, many of these species are also restricted to living in the vicinity of canebrakes (as in Platt et al. 2001). 

Cattle

Although cattle are not dependent upon cane for habitat, cattle can utilize cane for forage and have done so for many years.  Cane is one of the most nutritious native forage plants in the eastern U.S. and the culms remain palatable during the winter months throughout most of its range (Hilmon et al. 1965).  According to Grelen and Hughes (1984), crude protein, phosphorus, and calcium contents are well above the requirements for maturing livestock.  The digestible nutrients in cane foliage are highest during May and June then decline rapidly during the remaining summer months (Smart et al. 1960). 

Overgrazing can pose a threat to cane stand survivability.  During the spring, when new culms are emerging, cattle should be removed from cane stands to assure that a sufficient number of stems can fully develop to maintain the stand.  Overgrazing will result in a reduction of stem density as well as reduce the size of cane stems and leaves (Hughes 1966).

Giant cane riparian buffer zones have been shown to be effective at attenuating nutrients and sediment from agricultural surface and subsurface runoff.  A field-scale study in a southern Illinois non-tile drained agricultural watershed investigated cane’s ability to reduce sediment and nutrients from overland flow, soil water, and groundwater.  Cane generally outperformed native forest vegetation as a riparian zone species in terms of nutrient and sediment water quality protection (Table: Influence of canebrakes on water quality).  Thus, cane offers promise as a species that could be included in multi-species riparian buffer designs. 

Canebrakes are an early-succession community that are maintained by and thrive, in a large part, as a result of periodic fire.  In addition to historic lightning-induced fires, canebrakes were maintained by Native Americans through the use of prescribed fire every 7 – 10 years (Platt and Brantley 1997; Barden 1997).  Also, large canebrakes often flourished in abandoned Native American agricultural fields, which likely accounts for many of the historical canebrake descriptions (Platt and Brantley 1997; Brantley and Platt 2001).  Presently, the suppression of fire is one of several purported reasons for the decline of canebrakes (Hughes 1966; Brantley and Platt 2001).

Cane is adapted to fire disturbance in that it produces heavy rhizomes.  These underground stems serve as aerial culm support, food reserves, and asexual recruitment beyond the reach of surface fires (Hughes 1966).   Above-ground vegetation is highly flammable and quickly burned by fires, but new culm growth from these rhizomes is swift due to food stored during the summer and early fall (Hughes 1966; Platt and Brantley 1997).  This strategy is effective in out-competing other woody vegetation (Hughes 1966).  Post-fire culm regeneration is rapid (up to 1½” per 24 hrs) and stands tend to remain even-aged 2-3 years post-fire disturbance, becoming impenetrable, uneven-aged thickets after several years (Hughes 1966; Platt and Brantley 1997).  The average canebrake stand age will remain about 3-4 years however individual Arundinaria stems may reach 10 years in age (Hughes 1966).  After about 10 years of protection from fire, canebrakes reach maturity and are succeeded by other woody vegetation (Brantley and Platt 2001). 

Giant cane, like many other species of bamboo, displays mast flowering (synchronized flowering among multiple individuals at intermittent intervals) and is semelparous (flower/fruit once and then die).  This trait of bamboos is somewhat unusual in that most masting species are iteroparous (flower/fruit multiple times) (Silverton 1980).  Further, the masting cycle of bamboo is considerably delayed (up to over 50 years) compared to most other mast producing species (3-7 years) (Platt and Brantley 1997; Keeley and Bond 1999).  Therefore, once a cohort of seed has germinated and established into individual plants, canebrakes are heavily dependent upon vegetative reproduction for stand development. Without a seed crop, initial establishment of giant cane can be accomplished through planting of culms propagated from rhizomes (Zaczek et al. 2004).  Masting, in giant cane and in general, has often been considered to be a “predator satiation” mechanism, i.e. flowering irregularly so that seed predators are kept at low enough levels not to destroy a mast fruit (Janzen 1976; Keeley and Bond 1999).  However, the mast flowering, semelparity, delayed reproduction, and gregarious growing habits of bamboo have been linked to high-intensity fires (Keeley and Bond 1999; but see Saha and Rowe 2001).  Delayed reproduction and semelparity can produce high levels of fuel, and thick stands generate continuous fuel loads, both encouraging fire and consequently eliminating other woody species (Keeley and Bond 1999).  Mast flowering synchronizes seed dispersal and seedling recruitment in these canopy gaps and semelparity concentrates the breeding effort to an optimum time (Keeley and Bond 1999).  The specific factors that induce flowering however are elusive, but appear to be a combination of external (temperature, drought) and internal (genetic) controls (Janzen 1976, Platt and Brantley 1997)

Although several traits of Giant cane (Arundinaria gigantea) make it well adapted to periodic fire (Hughes 1966), canebrakes are not commonly managed using prescribed burns in the Southeast because of the dangers associated with burns and the potential associated fauna loss.  Canebrake fires are often intense and spread rapidly; therefore they can be difficult to control.  However, in cases where prescribed fire can be safely used, the following studies can help managers to plan optimum burning intervals. 

The periodicity of fire greatly affects cane performance.  Frequent burning favors fire resistant trees and shrubs, and annual growing season burns will eliminate cane by exhausting the rhizome food reservoir (Platt and Brantley 1997).  The fire interval for giant cane was 3-5 years in colonial times, but now 10 years is recommended to keep cane most productive (Hughes 1966). 

Fuel loads reach a maximum (7 tones per acre) after 3-4 years; therefore if fire hazard reduction is desired, a shorter burn interval of 3-5 years is optimal (Hughes 1966).  Shorter return interval may also be needed during restoration to reduce woody competition. 

Winter as well as spring/summer burns are reported to improve cane vigor (Platt and Brantley 1997).  Periodic summer and annual winter burning conducted over a period of 20 years increased the herbage yield of Arundinaria in the Coastal Plain of South Carolina (Lewis and Harshbarger 1976), and spring/summer burning in Florida pinelands reestablishes the cane’s role as a natural ecotone between wetland and longleaf pine (Pinus palustris) communities (Stevenson 1991).