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Information on fi eld management practices for seed production of newly domesticated grasses native to the southern Great Plains of North America has not been well documented. This study was conducted to document seed yield responses of one accession of plains bristlegrass [Setaria vulpiseta (Lam.) Roem. & Schult.] and three accessions of streambed bristlegrass [Setaria leucopila (Scribn. & Merr.) K. Schum.] to 0, 50, 75, 100, and 140 kg N ha −1 yr −1 under irrigation at Stephenville and Beeville, TX, during 2005 and 2006. The soil at Stephenville was a Windthorst fi ne sandy loam, mixed, thermic Udic Paleustalfs and at Beeville a Parrita clayey, mixed, active, hyperthermic, shallow Petrocalcic Paleustolls. Seed yields across N levels at Stephenville in year of establishment ranged (p < 0.05) from 57 to 753 kg ha −1 yr −1 . October seed yield of accession 648 increased (p < 0.05) 305% with 75 kg N ha −1 compared to the no-N treatment at Beeville. Seed production peaked at 328 kg ha −1 for accession 648 and 352 kg ha −1 for accession 715 in spring 2006 at Beeville. Infl orescence density was positively correlated to seed yield (from 81 to 93%). Optimum bristlegrass N fertilizer management varied with accession, location, and year.

Of 20 blood samples from nilgais from Mexico, five were polymerase chain reaction-positive for Babesia bigemina and one for Babesia bovis. Positive samples had the expected 170 (B. bigemina) and 291 (B. bovis) base pairs and were identical to Gen- Bank B. bigemina accession S45366 and B. bovis M38218.

Migration of sand dunes damages range improvements in the Texas Coastal Sand Plain. We determined effects of mulching with native prairie hay and an open weave geotextile fabric, seeding, fertilization, and transplanting on plant species canopy cover on inland sand dunes. We compared applying native hay vs. a synthetic geotextile material to inhibit wind erosion, seeding ‘Alamo’ switchgrass (Panicum virgatum L.), ‘Mason’ sandhill lovegrass (Eragrostis trichodes [Nutt.] Wood), and partridge pea (Chamaecrista fasciculata [Michx.] Greene) vs. no seeding, and fertilization with 468 kg ha-1 of 45:45:90 (N:P:K) vs. no fertilization. The same treatments were compared in a second experiment except that switchgrass, sandhill lovegrass, vetiver (Vetiveria zizanoides [L.] Nash ex Small), and giant reed (Arundo donax L.) were transplanted rather than seeded. Treatments were applied during March and April 1994 and canopy cover of vegetation in each experimental unit was estimated in October 1994, 1995, and 2004. Livestock were excluded from the study sites. The geotextile fabric degraded within 4 months and was replaced with coastal Bermuda (Cynodon dactylon [L.] Pers.) hay. Fertilization plus native hay mulch resulted in greater (P < 0.05) canopy cover of purple sandgrass (Triplasis purpurea [Walt.] Chapm.), sandbur (Cenchrus incertus M. A. Curtis and C. echinatus L.), and snakecotton (Froelichia spp.) than other treatments in 1994. In 1994 and 1995, canopy cover of switchgrass and sandhill lovegrass was greater (P < 0.05) with a combination of geotextile fabric and commercial hay, seeding, and fertilization than in other treatments. Vegetation composition and canopy cover were similar (P > 0.05) across treatments in 2004 in both experiments. Fertilization, seeding, and transplanting appear unnecessary to establish vegetation on dunes protected from livestock grazing when mulch is applied to inhibit sand movement.