Litter may be an important means by which invasive plants colonize and maintain dominance in native ecosystems. Invasive plant litter can decompose quicker than that of native plant litter, thus speeding up nutrient cycling rates and affecting competitive relationships. In contrast, it may decompose more slowly than that of native plants and thereby alter the environment and preempt habitat. Reed canary is an invasive plant in tallgrass prairie lowlands throughout much of the central North American grasslands.  Reed canary monocultures in lowlands often have thick mats of litter. The litter in these lowlands, often inundated with standing water, may not burn as readily as litter in drier, upland locations. Furthermore, we found that reed canary leaf litter had lower rates of decomposition than that of big bluestem, a native C4 grass.

Results/Conclusions

We set up a series of field manipulations of litter to test the idea that reed canary litter lowers early growing season soil temperatures and suppresses the emergence and growth of co-existing native, C4 grasses. The study site was Allwine Prairie, a restored, tallgrass prairie in eastern Nebraska. Results indicate that reed canary litter lowered early spring soil temperatures and differentially affected the tillering and growth rates of its own tillers and those of the native C4 grasses.