March, 1928] agricultural experiments 1927 25 



Effect of Acid Phosphate 



The fact that acid phosphate has previously been found to stimulate to 

 a marked degree the early growth of tomato plants led to a study of this 

 fertilizer on strawberries by J. R. Hepler. A series of eight treatments 

 was repeated with four different plots to each treatment; 20 tons of manure 

 per acre were applied to each plot, with additional applications of acid 

 phosphate in varying amounts, also muriate of potash and gypsum; to 

 one series 40 tons of manure per acre were applied. Commercial fertilizer 

 was distributed after the plants were set and was put between the rows so 

 there was very little burning. A count of the runners and runner plants 

 originating from twelve typical mother plants from each plot was taken at 

 intervals from July 6 to August 18; from the results it w'as clear that the 

 phosphorus had no pronounced effect on vegetative growth. Those plots 

 to which 40 tons of manure per acre had been applied for seven seasons 

 gave a marked increase, 30 per cent, over those receiving only 20 tons per 

 acre per year. Plant production was low on the potash plots. 



USE OF FERTILIZER ON CABBAGE 



The value of applications of manure and fertilizer in cabbage production 

 was shown in a series of plots in an experiment conducted by J. R. Hepler. 

 One-half of the land was fertilized with stable manure at the rate of 20 

 tons per acre. Eleven different fertilizer treatments were used. Seven 

 contained nitrogen in an amount equivalent to that applied in ten tons of 

 stable manure, the treatment known as the check. In addition there 

 were two acid phosphate and one muriate of potash series. 



Notwithstanding the fact that the season Avas very wet and yields 

 consequently low and variable, it was evident that the plots receiving 

 inorganic forms of nitrogen or commercial fertilizer almost invariably 

 outyielded the extra-manure plots in the manured half. Where no 

 manure was used, except on the check plots, the manure gave more 

 pronounced results. 



Except in one instance the yields of the 5-8-7 plots were high. The 

 nitrate of soda plots were consistently high, while tankage yields were 

 low. (Hatch Fund.) 



STALK BORER STUDIED 



A study of the life history of the stalk borer, an insect often confused 

 with the European corn borer, was completed this year by P. R. Lowry. 

 Though not a pest of major importance, the stalk borer annually causes 

 considerable loss in vegetable and flower gardens. Infestation may be 

 prevented by plowing or closely mowing grassland or weed areas around 

 cultivated fields and gardens, it was found, from about the middle of 

 August to the first week in September, thus preventing egglaying in these 

 areas. Mowing infested weeds or grasses while the larvae are still in the 

 active feeding stage is more likel}- to increase the infestation in cultivated 

 crops. Burning weeds and grasslands from November to April will 

 destroy the eggs. Especially prized plants may be protected by collars 

 with a band of tanglefoot around the outside. 



Further details in the studies of this insect have been published in a re- 

 port of the project in Technical Bulletin No. 34, "The Stalk Borer." 

 (Hatch Fund.) 



