44 BULLETIN 1190, U. S. DEPARTMENT OF AGRICULTURE. 
156. rasterization of cream for buttermaMng: Part I, Effect on quality and chemical composition. By 
Martin Mortensen, W . G. Gaessler, and W. H. Cooner. — Part II, Bacteriological studies. By 
B. W. Hammer. Dec, 1914. 
157. Improving Iowa's peat and alkali soils. ByW.H. Stevenson and P. E. Brown. June, 1915. 
158. Preservative treatment offence posts. By G-. B. MacDonald. Aug., 1915. Abridged edition, Dec., 
1915. 
159. Farm leases in Iowa. By O. G. Lloyd. Sept., 1915. Abridged edition, Dec, 1915. 
160. Grape pruning: The spur and long cane systems compared. By T. J. Manev. Oct., 1915. 
161. Mamtaining fertility in the Wisconsin drift soil area in Iowa. By W. H. Stevenson, P. E. Brown, and 
I. W. Forman. Oct., 1915. 
162. Two strawberry slugs. By R. L. Webster. Nov., 1915. Also popular edition. 
163. Late potato blight in Iowa. By A. T. Erwin. Apr., 1916. 
164. Studies on the market milk of Iowa. Complete with appendix of tables. By B. W. Hammer and A. J. 
Hauser. Apr., 1916. 
165. Influence of environment and breeding in increasing dairy production. By H. H. Kildee and A. C. 
McCandlish. May, 1916. 
166. Community hog houses. By J. B. Davidson, J. M. Evvard, and W. G. Kaiser. May, 1916. Also 
abridged edition, July, 1916. 
167. Rotation and manure experiments on the Wisconsin drift soil area. Bv W. H. Stevenson and P. E. 
Brown. Oct., 1916. 
168. Silage and silage fermentation. By A. R. Lamb. Dec, 1916. 
169. The weather and honey production. By L. A. Kenoyer. Mar., 1917. 
170. Evergreen trees for Iowa. By G. B. MacDonald. Mar., 1917. Also abridged edtion. 
171. Bordeaux spray for tip burn and early blight of potatoes. By A. T. Erwin. July, 1917. 
172. Managing a tuberculous herd: Part I, History of the tuberculous herd at Iowa State College since 1909. 
By W. H. Pew.— Part II, Plans for the control and eradication of tuberculosis. By C. H. Stange. 
July, 1917. 
173. The box elder aphid (Chaitophorus negundlnia Thomas). By R. L. Webster. Oct., 1917. 
174. Bacteria in ice cream— H. By B. W. Hammer and E. F. Goss. Dec, 1917. 
175. Improving the oat crop. ByX. C. Burnett. Mar., 191S. 
176. A successful Iowa shed roof poultry house. Bv G. M. Turpin and M. F. P. Costelloe. Mar., 1918. 
177. The "alkali" soils of Iowa. By R. L,. Bancroft. Mar., 1918. 
178. The nesting habits of the hen. By G. M. Turpin. May, 1918. 
179. The strawberry leaf-roller (A ncylis comptana Frohl.). By R. L. Webster. Nov., 1918. - Also abridged 
edition, April, 1918 
180. Factors which influence the yield and consistency of ice cream. Bv Martin Mortensen. May, 1918. 
Mav, 1918. 
181. Baby beef production. By W. H. Pew and J. M. Eward. Oct., 1918. 
182. Limiting the grain ration for fattening cattle. By W. H. Pew, J. M. Eward, and Russell Dunn. 
Oct., 1918. 
1S3. Soil erosion in Iowa. By E. E. Eastman and J. S. Glass. Jan., 1919. 
181. A rural social survev of Orange Township, Bdackhawk County, Iowa. By G. H. Von Tungeln, W. A. 
Brindlev, arid H. B. Hawthorn. Dec, 1918. 
185. Corn surmlements and substitutes for fattening lambs. By Russell Dunn and J. M. Eward. Jan., 
1919t 
186. A bacteriological study of the method of pasteurizing and homogenizing the ice cream mix. ByB. W. 
Hammer and L. R. Sanders. Mar., 1919. 
187. Soiling crops for milk production. By L. S. Gillette, A. C. McCanalish, and H. H. Kildee. Mar., 1919. 
188. Influence of environment and breeding in increasing dairy production, II. By A. C. McCandlish, 
L. S. Gillette, and H. H. Kildee. Mar., 1919. 
189. Silo construction. By C. K. Shedd and W. A. Foster. Apr., 1919. Revision of 141. 
190. Bacteriological results obtained in practice with vat nasteurization and with one of the final package 
methods. By B. W. Hammer. July, 1919. 
191. Reclaiming Iowa's "push" soils. By L. W. Forman. Nov., 1919. 
192. Cold storage for Iowa apples, third progress report: A_, Control of certain diseases of cold-stored apples; 
B, Changes of temperature in cold-stored apples. By W. E. Whitehouse, S. A. Beach, and T.- 
J. Maney. Dec, 1919. 
193. A rural social survey of Lone Tree Township, Clay County, Iowa. By G. H. Von Tungeln and W. A. 
Brindley. Mar., 1920. 
EESEAKCH BULLETINS. 
1. The chemical nature of the organic nitrogen in the soil. By S. L. Jodidi. June, 1911. 
2. Some bacteriological effects of Uming. By P. E. Brown. Aug., 1911. 
3. The chemical nature of the organic nitrogen in the soil: Parts 2-3, Influence of various factors on 
decomposition of soil organic matter. By S. L. Jodidi and A. A. Wells. Oct. 1911. 
4. Bacterial activities in frozen soils. By P. E. Brown and R. E. Smith. Jan., 1912. 
5. Bacteriological studies of field soils : I," The effect of lime. By P. E.Brown. Feb., 1912. 
6. Bacteriological studies of field soils: II, The effects of continuous cropping and various rotations. By 
P. E. Brown. Mar., 1912. 
7. Volatile aliphatic acids of corn silage. By A. W. Dox and R . E . Neidig. June, 1912. 
8. Bacteria at different depths in some typical Iowa soils. By P. E. Brown. May, 1912. 
9. Amino acids and acid amides as sources of ammonia in soils. ByS. L, Jodidi, E.H. Kellogg, and R, S. 
Snyder. Nov., 1912. 
10. Lactic acid in corn silage. By A. W. Dox and R . E . Neidig. Mar., 1913. 
11. Methods for bacteriological examination of soils; media for quantitative determination of bacteria in 
soils. By P. E.Brown. June, 1913. 
12. Chemical studies of the lime sulfur-lead arsenate spray mixture. By W. E . Ruth. June, 1913. 
13. Baeteriologicalstudiesoffieldsoils: HI, The effect of barnyard manure. By P. E.Brown. Sept., 1913. 
14. The specific heat of m ilk and milk derivatives. By B. W. Hammer and A, R. Johnson. Oct., 1913. 
15. A bacteriological study of blue milk. By B. W. Ha m mer. Feb., 1914. m 
16. Chemical changes during silage formation. By R. E. Neidig. July, 1914. 
17. Determination of ammonia in soils. Bv R. S. Potter and R, S. Snyder. Oct., 1914. 
18. Sulfofication in soils. By P. E. Brown and E. H. Kellogg. Dec, 1914. 
19. Bacteriological studies on the coagulation of evaporated milk. By B. W. Hammer. Jan., 1915. 
20. Bacteriological studies on two yellow milk organisms. By B. W. Hammer. Jan., 1915. 
21. Hardinessin the apple as correlated with structure and composition. BvS. A. Beach and F.W. Allen, 
jr. Mar., 1915. 
22. Slimy and ropy milk. By R. E. Buchanan and B. W. Hammer. July, 1915. 
23. Relation of moisture to seed production in alfalfa. By J. N. Martin. July, 1915. 
