649 



phosphoric acid in fjround plio.si)hatic rock was taken part in by three 

 iariiiers in 1888. Tlie crude pbo.s[)hates used were finely ground South 

 Carolina rock aiul Caribbean Sea guano. Each trial was on 10 tenth- 

 acre plats, fertilized as follows: finely ground South Carolina rock 1,000 

 pounds per acre, acid treated rock 500 pounds, and Caribbean Sea 

 guano 72.") pounds, were each used in combination with 150 pounds sul- 

 phate of ammonia and 100 pounds muriate of potash, on two plats; 

 and to compare the effects of thQ phosphates the same mixture of sul- 

 phate of ammonia and muriate of potash, without phosphate, was used 

 on two plats. Two plats received no fertilizer. Potatoes were grown 

 in one experiment and corn in the other two. The tabulated yields of 

 the crops in each experiment indicate — 



(1) That the iusoliililo phosphoric acid ia the finely ground South Carolina rock and 

 the finely gronnd Caribbean Sea gnano was able to furnish a considerable amount of 

 phosphoric acid to tlie crops ; (2) that the first crops were not able to avail them- 

 selves of as much phosphoric acid from the 272 pounds furnished by the 1,000 pounds 

 of finely ground South Carolina rock and the 725 pounds of Caribbean Sea guauo 

 as from the 65 pounds soluble phosphoric acid furnished by the 500 pounds of acid 

 South Carolina rock. 



The results of pot experiments with oats, using the same fertilizing 

 materials, "leave little room to doubt that a considerable amount of 

 l)hosphoric acid was obtained by the plants from the crude phosphatic 

 rock, amounting in the case of the Caribbean Sea guano to enough to 

 produce more than an average crop of grain." Pot experiments with 

 oats in which feldspar w'as substituted for muriate of potash, indicated 

 that the potash in the feldspar was available to the crop. 



The phosphates used in the pot experiments were of the same kind 

 and composition as those used in the field experiments. 



Experiments in GROwiNa mixed grain, W. Balentine, M. S. 

 (p. 111). — Mixtures of peas and oats and of peas and barley were grown 

 on two plats and compared with oats alone on another plat. The oats 

 were attacked with rust, and the experiment was thus rendered incon- 

 clusive. 



Tests of varieties of barley, oats, peas, and potatoes, W. 

 Balentine, M. S. (pp. 145-147). — Tabulated notes on 2 varieties of 

 barley, 5 of oats, G of peas, and 107 of potatoes. 



Report of botanist and entomologist, F. L. Harvey, M. S. 

 (pp. 148-256). — Besides the work recorded in this report, the botanist 

 and entomologist of the station during 18S9 made studies on the 

 codling moth, white-marked tussock moth, fall web-worm, and a scale 

 insect affecting elm trees in Maine; collected herbarium specimens of 

 grasses and other economic plants, and seeds of weeds and other plants; 

 examined fungi, weeds, grasses, etc., sent to the station for determina- 

 tion; and read papers on "Fungi injurious to fruits," before the Maine 

 State Pomological Society (to appear in its Annual Report), and on 

 "The apple maggot," before the Pomological Society at Norway, Maine. 

 27688— No. 11 3 



