INFLUENCE OF LATITUDE ON FLOWERING OF
SWEETCLOVER IN TEXAS

G.W. Evers and G.R. Smith
Texas A&M University Agricultural Research & Extension Center, P.O. Box 200
Overton, Texas, USA 75684

New cultivars of white annual sweetclover with multi-stem crowns and low coumarin levels are being developed for the neutral to alkaline soils in central Texas. Hubam sweetclover and four maturities of Emerald sweetclover were evaluated in south (28.45°N), central (30.59°N), and north (32.46°N) Texas to identify the best maturity. Plant growth was earlier at the southern location because of milder winter temperatures, followed by the central and then the northern locations. At each location, the percentage of Emerald plants reaching the reproductive stage generally occurred according to maturity. At all locations the percentage of plants reaching the reproductive stage ranged from about 80% for Emerald maturity 2 to about 5% for Emerald maturity 10/11 until after April. Flowering of Hubam was slightly later than Emerald maturity 7. Emerald maturity 7 was the best entry for pasture or hay and Emerald maturity 2 was best suited as a winter cover crop in a summer crop rotation.