338 EXPERIMENT STATION RECORD. [Vol. 43 



of 1918, the fertilizer tended to stimulate production. On the tilled plat, fer- 

 tilizer increased the yield about one-third, and on tJie grass plat more than 

 four times. Where the fertilizer was applied, the rye cover-crop yielded at 

 the rate of 3.6 tons per acre, while the unfertilized plat yielded only 1.8 tons 

 of rye per acre. 



A determination was made of tlie amounts of nitrates in the soil before and 

 after fertilization. The first samples were procured the day before the fer- 

 tilizer was applied. The grass plat contained the smallest amount of nitrates, 

 suggesting that the grass uses the nitrates in its own growth. The largest 

 iiiiMjiunt of nitrates was present under the mulch. The second lot of samples, 

 secured on May 15, showed that the fertilized plats carried from 2 to 10 times 

 the amount of nitrates in the soil carried by the unfertilized plats. Tliis was 

 not true in the grass plats, where the increase was much less marked. 



Judged by the results secured in 1918, pruning has continued to prove a 

 dwarfing process, both to the root and top of apple trees. Heavy pruning re- 

 duces early bearing. 



The results of cover-crop experiments confirm previous conclusions. Gen- 

 erally speaking, those cover-crops which have the greatest value in the orchard 

 are those crops which produce the greatest bulk of vegetable matter to return 

 to the soil. 



In the stock and scion experiments with apples, considerable progress has 

 been made in securing own-rooted trees. In the work at Bedford, nearly twice 

 the number of trees had rooted from the scion the second year after planting 

 than were rooted the first year. 



The results of dusting experiments for the first season show that dusting 

 was more expensive than spraying and was not so effective in the control of 

 apple scab. Dusting controlled codling moth and curculio as well as did spray- 

 ing. Ninety-five per cent of the cost of dusting was for material, while under 

 .spraying only 65 per cent was for material and 35 per cent for labor. 



Fertilizer experiments are being condiK-ted to determine whether nitrate 

 of soda is ordinarily needed in Indiana orchards, and if so, when is the best 

 time to apply it. Among the results thus far secured, leaf studies indicate 

 that nitrate of soda increased both the green and dry weight of the leaves. 

 Fertilized trees made more growth in three out of four cases. The terminal 

 growth amounted to about one inch more than the check plats. The time at 

 which the nitrate was applied, that is, several weeks before or several weeks 

 after bloom, made very little difference so far as growth is concerned. Of 5 

 orchards under experiment in 191S, only one gave a consistent response to the 

 use of nitrate. This orchard Vas the only one in sod and was on the poorest 

 land in any of the plats. The trees in this orchard bore twice as much fruit 

 as those not fertilized, thus indicating that on poor sod lands the fruit crop 

 will be improved the first season by applications of nitrate, whereas in culti- 

 A^ated orchards the results the first season may be negative. 



The work with vegetables in 1918 was largely with crops used by tlie can- 

 nery. Tomato seed was selected and distributed for the season of 1919 Avith 

 satisfactory results. A variety test containing 14 different varieties and 30 

 strains of tomatoes was carried on. The yields in this test ranged from 1.8 

 tons to over 8 tons per acre. Different strains of the Greater Baltimore va- 

 riety yielded from one and one-third to seven and two-thirds tons. In tomato 

 fertilizer experiments conducted in 1918, acid phosphate applied at rates of 

 100 and 300 lbs. per acre gave average net increases of $19.66 and $32.18 

 per acre. Lime, 2,000 lbs. per acre, used with 100 lbs. acid phosphate reduced 

 the net gain to $6.38 per acre ; used with 300 lbs. of acid phosphate, it reduced 



