A COMPARISON OF LUCERNE VARIETIES IN SOUTH-WEST SCOTLAND

Five early, three mid-season and two late varieties of lucerne were grown in drills in a replicated plot experiment at the Hannah Dairy Research Institute in south-west Scotland in the period 1956–59, inclusive. The lucerne was cut three times each year after the year of establishment (1956).
Average yields were 10,200 lb. of dry matter and 1970 lb. of crude protein per acre in the first harvest year, but declined rapidly to 6290 lb. of dry matter and 1190 lb. of crude protein per acre in the third year. On average, the early types of lucerne gave the highest yields of dry matter and crude protein. Over the three harvest years of the experiment, Flandria was the highest yielding variety and New Zealand B the lowest. The distribution of dry-matter yields averaged over all varieties was 44, 29 and 27% for cuts 1, 2 and 3, respectively.
The crude-protein content of the herbage from all the varieties was high, 63% of the values being greater than 19%. Grimm, a late variety, had the highest crude-protein content.
With all varieties tiller density declined rapidly from the first to the second harvest year, but increased again at the third harvest year.
11–34% of the total yield of dry matter in the second harvest year consisted of weed grasses, but this was reduced in the following year by spraying the plots with Dowpon, a selective herbicide.