110 TWENTY-THIRD ANNUAL YEAR BOOK— PART III. 



yields in four-year rotations were 1.6 tons clover, 57.5 bushels first-year 

 corn, 51.6 bushels second-year corn and 48.3 bushels oats. In the same 

 rotation of clover, corn, corn and oats, manure and lime increased the 

 yield up to the following figures: 'Clover, 1.8 tons per acre; first-year 

 corn, 62.1 bushels; second-year corn, 56.1 bushels; and oats, 56.3 bushels 

 per acre. Similar results have been obtained on soils pronouncedly sour, 

 such as require from two to three tons of limestone per acre. The lesson 

 was that liming soils pays and approximately 75 per cent of Iowa soils 

 are in need of lime. In this connection the soils department showed a 

 new and very simple test for soil acidity that any farmer can readily 

 make himself. The product used for making the test is called "Richor- 

 poor." Any county agent can give information about where to buy "Rich- 

 orpoor" and how to apply it in testing soils for acidity. 



The department of botany displayed a number of the common plant 

 diseases affecting farm crops. One of these diseases — corn ear rot — was 

 featured. Last year Iowa corn suffered considerably from this disease, 

 which is a mold. It is also referred to as dry rot of corn. It flourishes 

 in years when much wet weather comes during the latter part of August 

 and the first part of September and may do considerable damage in some 

 sections of the state this year. The principal damage done by this dis- 

 ease, however, is in the spring at planting time in reducing the stand. 

 Seed corn may be infected with dry rot and not be noticed on the ears 

 unless a very close inspection is made. And even then it may not be 

 detected. Fortunately it can easily be found if the seed is given a germina- 

 tion test. When the mold is present it begins to grow as soon as the 

 corn sprouts and can be seen on the sprouts and their roots as a white 

 filmy mold growing all over these parts. Corn infected with the dry 

 rot fungus should not be planted, as it is sure to reduce the stand from 

 15 to 30 or more per cent, the exact amount depending upon the amount 

 of the fungus present on the seed kernels. All kernels affected with 

 this rot die before the sprouts come through the ground. Every farmer 

 should learn to recognize this disease and guard against it. 



The poultry department displayed some very interesting figures from 

 a poultry feeding test that has been in progress for nine months on the 

 college poultry farm. Results from five pens were shown. The birds 

 in each pen have been fed the same scratch grain and rye mash of grain 

 for nine months. In addition to these rations some pens were fed defi- 

 nite quantities of a high protein product as tankage, beef scrap, powdered 

 buttermilk, etc. The scratch grain for all pens was composed of two 

 parts by weight of shelled corn and one part of whole oats, while the dry 

 mash was composed of one-third by weight of ground corn, ground oats 

 and wheat middlings. 



Pen 5 received nothing but these feeds and produced 36.2 eggs per hen 

 in nine months. Pen 1 received 25 per cent of tankage mixed with the 

 basal dry mash and produced 60.5 eggs per hen in the same time. Pen 

 2 received 25 per cent beef scrap mixed with the basal dry mash and 

 produced 70 eggs per hen. Pen 3 received 25 per cent dried buttermilk 

 with the basal dry mash and produced 97 eggs per hen. Pen 4 received 



