We compared the Alamo variety with three selected cultivars, two from Georgia and one from Oklahoma.  All three were more vigorous in growth habit as compared to Alamo and were higher-yielding on some of the four soil-landscape positions studied. 

On each of these four positions we also established a seeding rate-nitrogen fertilizer rate interaction study.  In the year of establishment, we used five different seeding rates of the Alamo variety of 2.5, 5.0, 7.5, 10.0, and 12.5 lbs. pure live seed (PLS) per acre. In the second growing season, we applied four rates of nitrogen fertilizer, 0, 60, 120, and 180 lbs. N/acre on each of the seeding rates.  The effect of nitrogen and seeding rates varied across sites but on the most productive sites, the lower seeding and fertilizer rates were sufficient in the second growing season. 

Very few herbicides are available for weed control in switchgrass.  Research has been initiated on weed control strategies in both the establishment year and second growing season, with emphasis on control of very competitive problem grasses such as broadleaf signalgrass and crabgrass.  Control of grass competition in heavily infested areas is essential for good switchgrass establishment and subsequent future production.  Weed control options have been identified, but most are not currently labeled for switchgrass.

If switchgrass becomes a viable alternative crop, we hope to have effective and economical production strategies developed for producers.