General Description:  A perennial with 3-angled stems, long grass-like leaves, yellowish-green foliage, and 1 to 2 cm tubers at the ends of rhizomes.  Flowers are in spikelets at the ends of stems.  

Seedling:  Seedlings are not often found.  When present seedlings are very grass-like but soon develop the characteristic 3-sided base.

Mature Plant:  Rhizomes and tubers are present.  Tubers are 1 to 2 cm long, rounded, ridged or scaled, white at first, turning brown and then black.  Tubers are produced at the end of rhizomes beginning in late June and continuing into autumn.  A single plant may produce hundreds or several thousand in a season.  Most tubers are found in the first 15 cm of the soil.  They require a chilling period to break dormancy.  After germination, tubers produce a primary basal bulb 1 to 2 cm beneath the soil surface; the bulb develops fibrous roots, then rhizomes, secondary basal bulbs, and tubers.

Flowers and Fruit:  Individual flowers are inconspicuous, similar to those of grasses, and are organized into yellowish or brownish spikelets, 1 to 3 cm long and flattened.  They are present from July to September.  Spikelets occur at the ends of stems in terminal umbel-like clusters.  Bracts below the flower clusters are leaf-like and often longer than the flower clusters.  The single seed is enclosed within a 3-angled, yellowish-brown achene.

Distribution:  Found throughout the United States

Crops Affected:  Corn, Soybean, Tobacco, Turf and Vegetable Crops.

Animal Poisoning:  None

Similar Species:  Purple nutsedge has dark green leaves and stems and reddish-brown or purple spikelets, whereas yellow nutsedge has yellow-green leaves and stems and yellowish or brown spikelets.  Purple nutsedge develops tubers along the length of the rhizomes; yellow nutsedge tubers only form at the tips.  Although nutsedge may resemble grasses, grasses do not produce leaves in groups of 3 and do not have tubers or 3-angled stems.