Blue Sedge (Carex glaucodea Tuck. ex Olney)
↑Range - Expand
Legend | Color |
Native | |
Native or Not Present |
This tentative map is based on our own research. It may have limited data on Canada and/or Mexico, and there is some subjectivity in our assignment of plants as introduced vs. expanded. Read more in this blog post.
↑Similar Plants
↑Habitat
Carex glaucodea is found in habitats that alternate between wet and dry conditions, most frequently those underlain by hardpan clay. Natural habitats include upland forests and prairies, occasionally swampy depressions in uplands, and rarely floodplains of small streams. The most common forest type it occurs in is oak-hickory, and it can also occur with pines. Among anthropogonic habitats it can be found in old fields and partly-shaded parks and gardens. It is rare in the northeast of its range.
It is most often found on clayey soils and soils underlain by a clay hardpan, on sites that are occasionally wet, but usually dry. It is usually found on acidic soils. These soils can form on a wide variety of substrates, including sandstone, granite, and unconsolidated clay soils in the coastal plain.
It usually colonizes sites that have experienced a light, local disturbance such as exposure of a small area of soil. It is usually restricted to sites with partial sun, but can occur in full sun on moister sites. The openness in the forested habitats where it occurs can arise from a combination of drought stress, stress from poor drainage, and poor nutrient availability.
Although it is fairly specific in its habitat tolerances, it can thrive in anthropogenic habitats. It can survive mowing to a degree, and, on sites underlain by clay soil, aggressive leaf-blowing that strips topsoil can sometimes create conditions for it to thrive, particularly where there is some shade from trees sloped topography creates the sort of sometimes wet, often dry conditions it likes. It also benefits from the soil disturbance in managed landscapes, which creates conditions favorable for its seedlings to establish. Humans may also have increased the habitat for this species by leading to deer overpopulation, as it is resistant to deer browsing.
↑Life Cycle
Carex glaucodea is a clumping perennial. It initially grows basal leaves, pressed closely against the ground. First-year plants usually do not bloom.
In the spring, the foliage and stems begin growing more upright, to the point of flowering, but shortly thereafter, the foliage and stems often flop over, with the seed spikes usually lying close to the ground as they mature. This change in growth habit likely serves several purposes. The brief, more upright growth habit captures more sunlight during a time of year that averages wetter in most of its range, and also facilitates wind pollination during flowering. Later, where this plant is often subjected to greater drought stress, the foliage falling flat against the ground reduces water loss, and the sprawling habit of the stems also helps the relatively heavy seeds to fall farther from the parent plant.
The basal foliage is semievergreen, remaining evergreen in milder climates.
↑Uses
Carex glaucodea is sometimes used as an ornamental plant, where it is valued for its distinctive blue foliage that is usually evergreen, its attractive flowers, its tolerance of both wet and dry conditions, and for its low height, which both allows it to survive occasional mowing, and can eliminate or reduce the need for mowing on sites where it is growing.
↑Related Plants
This species belongs to the Griseae section of the Carex genus; numerous other species in this section overlap with this one in range.
↑Links & External Resources
• Carex glaucodea (blue sedge) | USDA PLANTS Database (About This Site)
• Carex glaucodea | Go Botany (About This Site)
• Carex glaucodea | Biota of North America Project (BONAP) (About This Site)
• Carex glaucodea | Flora of North America (About This Site)
• Carex glaucodea | Missouri Plants (About This Site)
• Blue Sedge | Maryland Biodiversity Project (About This Site)
• Carex glaucodea Tuck. ex Olney | Plants of the World Online (POWO) (About This Site)
• Carex glaucodea Tuckerman ex Olney (Blue Sedge) | Digital Atlas of the Virginia Flora (About This Site)