Fire Effects on Weeping Lovegrass Tiller Density and Demographics

Prescribed burning is a common management practice applied to weeping lovegrass [ Eragrostis curvula (Schrad.) Nees], but little is known about tiller density and demographic response to burning. Our objectives were to determine fire effects on weeping lovegrass tiller density and demographics on a site, seeded in 1989, in western Texas. Tillers were sampled at 14‐d intervals in 1996 and 1997 to determine tiller density and demographics. Tiller density response to burning differed ( P = 0.0002 ) between years. Burning increased ( P = 0.0001 ) tiller density 61% compared with no burning in 1996, but did not affect tiller density ( P = 0.9264 ) in 1997. In 1996, tiller density ranged from 1068 to 2052 and 1623 to 2617 tillers m −2 in nonburned and burned areas, respectively. In 1997, tiller density ranged from 1337 to 2398 and 1313 to 2027 tillers m −2 in nonburned and burned areas, respectively. Tillers in nonburned and burned areas remained primarily vegetative throughout each growing season with few tillers advancing to reproductive and seed‐ripening stages, likely a response to poor fertility on the site. Burning increased reproductive tiller numbers by 238% compared with no burning in 1996, but few advanced to the seed‐ripening stage. In 1997, most reproductive tillers advanced to the seed‐ripening stage, likely responding to precipitation. Burning apparently altered the light environment and increased nutrient availability to weeping lovegrass. Yearly variation in the response to burning of weeping lovegrass tiller density and tiller demographics demonstrates that management must be based on current tiller populations.