82 MASS. EXPERIMENT STATION BULLETIN 355 



by growers produce the best and earliest yields. Work is being conducted both at 

 Waltham and at Amherst. The heavy rains during July flooded the plots at 

 Amherst, killing some of the plants and practically destroying the experiment. 

 At Waltham the damage was not so severe but there was a general reduction of 

 growth and vigor over all plots. The hurricane prevented completion of the 

 harvest records. 



It was apparent that if plants did not have the fruit formed before the heavy 

 rains they were unable to set and mature fruit after the weather improved. 



In general, the treatments that produced the best early yields also produced 

 the best total yields. The value of commercial fertilizer was shown this year 

 in that the plots which received manure but no fertilizer produced only about 

 half as much fruit as plots receiving manure and one ton of 5-8-7 fertilizer per 

 acre. 



In previous years, the plants not staked were low in early }ield but produced 

 almost as much fruit for the season as did the staked plants. This year, the wet 

 weather apparently affected the plants on the ground more than those staked, 

 because the early yields for the flat-culture plants were about one-third those 

 of the staked plants, and the total yield about one-half. 



The highest yield was from plants that had been potted and trained to a single 

 stem, largely because there are almost twice as many plants per acre when they 

 are trained in this manner. However, where land is scarce or expensive, the 

 training of plants to a single stem instead of the usual two would increase the 

 income per acre considerably. 



The plots that received no fertilizer, and the plot where the plants were not 

 staked, produced outstandingly low yields. There was a heavy set of fruit on 

 some plots and almost none on others when the storm blew the fruit off the vines. 



Vegetable Breeding for Improvement of Quality. (Robert E. Young, Waltham.) 



Lettuce, New York Type. (In cooperation with United States Department of 

 Agriculture.) This past season was very good for lettuce, and practically all 

 varieties headed well. The percentage of heads cut in growers' fields was from 

 25 to 100 percent better than in normal years. 



While it was a good year for the gowers, it was unsatisfactory for breeding 

 lettuce because almost all the strains headed well. The New York 12 strain in 

 the trials headed approximately 40 percent better than during the last two 

 years. The records indicate that in years of good weather New York 12 heads 

 at least as well as any other commercial strain, but when the weather is a little 

 adverse it is one of the first strains to show a reduction in the percentage of 

 marketable heads. 



Imperial 44, developed in California by the United States Department of 

 Agriculture, was tried. On the fairly heavy soils at Waltham it headed excellently 

 and was of fair size. Some of the same plants in trials on a light sandy soil in 

 Dighton headed only fairly well, and were too small to be salable. 



Trials conducted on a commercial lettuce grower's farm in Dighton, in the 

 center of the most intensive lettuce section, have shown that there is considerable 

 difference in behavior of strains as compared with those grown at Waltham. 



Varieties New York 12 and 15 are still recommended for growers' use. Imperial 

 847 and 44 are certainly worth a trial. 



Greenhouse Lettuce. The supply of stock seed of Bel-May lettuce was replenished. 

 The work with the hybrid material under way for the past few years has been 

 continued, but much purification remains to be done before a satisfactory lettuce 

 can be obtained. The quantity of greenhouse lettuce grown for the Boston 

 Market remains about the same. 



