ANNUAL REPORT, 1946-47 57 



and Butternut squash. While progress has been made in the development of 

 strains of celery, rutabaga, and greenhouse cucumber better adapied for local 

 use, it is insufficient to justify detailed discussion. 



Broccoli. The 1946 fall broccoli plots came into production during unseason- 

 ably warm weather with the result that many varieties and strains failed to make 

 a marketable head. Under these conditions, a fall type, tentatively called Strain 

 29, was outstanding. This strain is a slow-growing type which requires so much 

 time to produce the head that short periods of unseasonable weather have little 

 effect on it. It was tried in the spring and found worthless. Seed has been pro- 

 duced for expanded fall trials and further purification. 



The spring trials in 1947 showed the two strains recently developed for this 

 season, namely Waltham No. 7 and No. 11, to be outstanding producers as an 

 early crop. They also gave total yields considerably higher than that of the best 

 commercial variety. The commercial variety which was best in early yield was 

 only average when the total yields were considered; and the variety that ranked 

 next to Nos. 7 and 11 for total yield was only 75 percent as productive in the 

 early season. 



Thus, it would seem that we have been able to retain characteristics for good 

 early yield with the necessary vigor that makes for large total yields. Tests with 

 growers indicate that strains No. 7 and 11 have real value, but they require a 

 little more selection for uniformity. 



Carrot Seed Production. The maintenance of a supply of stock seed of the Field 

 Station strain of Hutchinson carrot has always been a part of the Carrot Breed- 

 ing Project. To produce this seed, which is supplied to the carrot seed growers, 

 a fall crop was grown and selected roots placed in a storage pit. In the spring 

 these were re-selected for shape and external color, and internal color was observed 

 by cutting off" the bottom third of the root. Then the roots were planted in the 

 field in early spring. By that method there was a small amount of crossing with 

 wild carrot, and the resulting hybrids were sometimes overlooked in the seed 

 fields in the west. This accounted for the presence of a small percentage of 

 white, yellow, and poor-shaped roots found in the local carrot fields. 



A method has now been developed whereby this seed is grown in the green- 

 house with bees used as pollinators, and it is mature before the wild carrot blooms. 

 By this procedure the off-color carrots were reduced from 2 percent in field- 

 grown stock to none in the greenhouse crop. It is planned to supply seed pro- 

 ducers an ounce or so of this elite stock seed, and they in turn can multiply the 

 seed in California where wild carrots are not a problem. 



The breeding of a better carrot continues, but last season work was considerably 

 handicapped by the presence of an unusually high percentage of aster yellows 

 which destroyed some of the best breeding lines. 



New York Type Lettuce. The testing of Waltham Imperial Lettuce on a 

 sufficient scale to really determine its place has been delayed by lack of seed. 

 The seed crops, both local and that grown in California, have been disappointing. 



In the 1947 crop in which early plants were set in the field, Waltham Imperial 

 showed much more uniformity of plants and in maturity than did Great Lakes. 

 At the time of the first cutting Great Lakes produced 55 percent marketable 

 heads while Waltham Imperial produced 70 percent. 



While Great Lakes, Waltham Imperial, and several other new strains of sim- 

 ilar type, have about taken care of the requirements for a late set lettuce, there 



