Feature Story
Bermudagrasses – An Update By Tom Samples and John Sorochan, University of Tennessee, Department of Plant Sciences
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ermudagrass, an aggressive sodforming and warm-season turfgrass, most likely originated in Africa and south and southeastern Asia. It is believed that the species was introduced into the U. S. in the mid- 1700’s from seed in hay used as bedding on ships sailing from Africa to America. Some turf-type bermudagrasses in today’s marketplace are non-seed bearing hybrids of two Cynodon species, C. dactylon (Common) and C. transvaalensis (African), and must be vegetatively established. Others are improved varieties of ‘Common’ bermudagrass and are prolific seed producers often referred to as ‘seeded-types’. Plants spread by both above- and below-ground stems referred to as stolons and rhizomes, respectively. Bermudagrass grows best in open areas receiving full sun and although a limited number of varieties have improved shade tolerance, the species is generally not well adapted in moderately to heavily shaded areas. Leaves and stems become strawbrown as plants enter dormancy each fall. A healthy, actively growing bermudagrass turf is dense, uniform, resistant to weed invasion and capable of quickly recovering from wear injury. Under ideal growing conditions, and in nutrient-rich soils, newly planted sprigs of several varieties may grow at the rate of ¾-inch or more per day.
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The species tolerates sandy to clayey soils, however both hybrid and common bermudagrasses grow poorly in infertile soils that remain wet for an extended period. Depending on management intensity level, the nitrogen (N) fertility requirement of bermudagrass usually ranges from ½ to 1½ lbs. of N per 1,000 sq. ft. per growing month. Bermudagrass turfs are often routinely dethatched and are susceptible to several patch diseases including pink snow mold (Microdochium nivale), large patch (Rhizoctonia solani) and spring dead spot (Ophiosphaerella spp.). Common insect pests include armyworm (Pseudaletia unipuncta), fall armyworm (Spodoptera frugiperda) and white grubs (larvae of several species of Scarab. beetles). Winter annual weeds such as annual bluegrass (Poa annua), common chickweed (Stellaria media), henbit (Lamium amplexicaule) and purple deadnettle (Lamium pupureum) may appear in bermudagrass turfs during winter dormancy. Several perennial weeds with energy-rich, below-ground bulbs or tubers such as yellow nutsedge (Cyperus esculentus), green (Kyllinga brevifolia) and false-green (Kyllinga gracillima) kyllinga, wild garlic (Allium vineale) and wild violet (Viola spp.) can become problematic as they compete with bermudagrass plants for water, nutrients, light and space.
TENNESSEE TURFGRASS April/May 2019 Email TTA at: info@ttaonline.org
