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Grease Grass Tridens flavus

Phonetic Spelling
TRY-dens FLA-vus
Description

A native ornamental warm-season bunchgrass in the Poaceae family.  It has attractive reddish-purple seed heads that appear in the late summer and persist into fall and are especially impactful when planted en masse.  It is a salt-tolerant grass and is often seen growing along roadside ditches. Its seed heads are oily, hence the common name grease grass, and are a food source for birds and mammals.

Purple Top is a perennial warm-season grass that grows 3-5 feet tall and 3 feet wide. It has a rich hue to its foliage as it develops each spring. Shortly after the foliage matures, the flower spikes develop as purple panicles that bloom from August to November. Deer resistance is high.

This is a larval host plant that supports various skipper larvae and the Common Wood-Nymph (Cercyonis pegala) which has one brood from late May to October. Adult Common Wood-Nymph butterflies feed on rotting plant matter. This species is also the larval host of a number of butterflies and moths, including Polites origenes (Crossline Skipper), Pompeius verna (Little Glassywing), and Poanes viator (Broad-winged Skipper). The plant provides excellent cover year-round.

Seasons of Interest:

Bloom: Summer-Fall, August-October; Fruit/Seed/Nut: Fall/Winter

Insects, Diseases, or Other Plant Problems:

See this plant in the following landscape:
Cultivars / Varieties:
Tags:
#purple#moth caterpillar host#salt tolerant#cover plant#NC native#deer resistant#skipper butterflies#native garden#pollinator plant#native ornamental grass#larval host plant#food source fall#NC Native Pollinator Plant#food source herbage#bird friendly#food source hard mast fruit#mammals#butterfly friendly#Piedmont Mountains FACU#Coastal FACU#Audubon#common wood-nymph butterfly#perennial#wildlife friendly
 
Cultivars / Varieties:
Tags:
#purple#moth caterpillar host#salt tolerant#cover plant#NC native#deer resistant#skipper butterflies#native garden#pollinator plant#native ornamental grass#larval host plant#food source fall#NC Native Pollinator Plant#food source herbage#bird friendly#food source hard mast fruit#mammals#butterfly friendly#Piedmont Mountains FACU#Coastal FACU#Audubon#common wood-nymph butterfly#perennial#wildlife friendly
  • Attributes:
    Genus:
    Tridens
    Species:
    flavus
    Family:
    Poaceae
    Life Cycle:
    Perennial
    Recommended Propagation Strategy:
    Division
    Seed
    Country Or Region Of Origin:
    North America, NC
    Distribution:
    AL , AR , CT , DC , DE , FL , GA , IA , IL , IN , KS , KY , LA , MA , MD , MI , MN , MO , MS , NC , NE , NH , NJ , NM , NY , OH , OK , PA , RI , SC , TN , TX , VA , VT , WI , WV
    Wildlife Value:
    Seed heads are a food source for birds and mammals. This is a larval host plant that supports various skipper larvae and Common Wood-Nymph (Cercyonis pegala) which have one brood from late May to October. Adult Common Wood-Nymph butterflies feed on rotting plant matter. This species is also the larval host of a number of butterflies and moths, including Polites origenes (Crossline Skipper), Pompeius verna (Little Glassywing), and Poanes viator (Broad-winged Skipper). It provides excellent cover year-round.
    Particularly Resistant To (Insects/Diseases/Other Problems):
    Salt, Deer, Drought, Erosion, Dry Soil, Air Pollution
    Dimensions:
    Height: 3 ft. 0 in. - 5 ft. 0 in.
    Width: 1 ft. 0 in. - 3 ft. 0 in.
  • Whole Plant Traits:
    Plant Type:
    Native Plant
    Ornamental Grasses and Sedges
    Perennial
    Woody Plant Leaf Characteristics:
    Deciduous
    Habit/Form:
    Clumping
    Erect
    Maintenance:
    Low
    Texture:
    Coarse
  • Cultural Conditions:
    Light:
    Dappled Sunlight (Shade through upper canopy all day)
    Full sun (6 or more hours of direct sunlight a day)
    Partial Shade (Direct sunlight only part of the day, 2-6 hours)
    Soil Texture:
    Clay
    High Organic Matter
    Loam (Silt)
    Sand
    Shallow Rocky
    Soil Drainage:
    Good Drainage
    Moist
    Occasionally Dry
    Available Space To Plant:
    12 inches-3 feet
    NC Region:
    Coastal
    Mountains
    Piedmont
    USDA Plant Hardiness Zone:
    4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b
  • Fruit:
    Display/Harvest Time:
    Fall
    Fruit Type:
    Caryopsis
    Fruit Description:
    Fruits display from September to November.
  • Flowers:
    Flower Color:
    Brown/Copper
    Cream/Tan
    Gold/Yellow
    Purple/Lavender
    Flower Inflorescence:
    Panicle
    Flower Value To Gardener:
    Good Cut
    Long-lasting
    Showy
    Flower Bloom Time:
    Fall
    Summer
    Flower Description:
    Purple panicles of spikelets appear July to October.
  • Leaves:
    Woody Plant Leaf Characteristics:
    Deciduous
    Leaf Color:
    Green
    Leaf Feel:
    Rough
    Leaf Type:
    Simple
    Leaf Arrangement:
    Alternate
    Leaf Shape:
    Linear
    Leaf Margin:
    Entire
    Hairs Present:
    Yes
    Leaf Length:
    > 6 inches
    Leaf Width:
    < 1 inch
    Leaf Description:
    Linear green leaves are shallowly grooved to flat and up to 16 inches long and 10 mm wide. Leaves tightly sheath the stem.
  • Stem:
    Stem Is Aromatic:
    No
  • Landscape:
    Landscape Location:
    Meadow
    Naturalized Area
    Woodland
    Landscape Theme:
    Native Garden
    Winter Garden
    Attracts:
    Butterflies
    Moths
    Songbirds
    Resistance To Challenges:
    Deer
    Salt