1. The percentages of winterkilling of winter wheat plants determined on date of seeding test trials during three consecutive years, 1923 to 1925, inclusive, were found to vary, depending upon the date on which the seed was sown. For a series of seedings made on or close to August 15, August 31, September 21, October 6, and October 19, the percentage of winterhardiness followed in decreasing order the seedings of September 21, September 4, October 3, October 17, and August 5, respectively. 2. The root development of plants for the various dates of seeding is strikingly different. The plants from the first seeding, August 18, show the greatest development of fall root system, followed in order by plants of the second, third, fourth, and fifth seedings. New root development in the spring usually proceded from the crowns of the plant. The old fall roots as a rule do not continue active growth in the spring, but subsequent spring root development continues from the crown of the plant. 3. Winterkilling did not occur, as a rule, from the fracturing of the roots, but because of the fact that the plants were raised out of the soil. As a result of this raising of the plant, death resulted through desiccation. This is an important factor in the late dates of seeding. If the spring season is humid, the dislodged plants may form new roots and become reestablished in the soil and continue growth. 4. Plants grown in soil, with 10% moisture content lived through the winter better and recovered better in the spring than did plants grown in soil having 25 to 30% moisture content. 5. Grain yields for the three years, 1922 to 1924 inclusive, are directly correlated with the amount of winterkilling. A low percentage stand of plants in the spring and also grain yield are not always indicative of high percentage of winterkilling. Especially is this true for the late seedings, namely, October 5 and October 19. It is on these late seeding dates that the greatest "heaving" of plants results which leads to plant desiccation. Therefore, death of plants in many of these instances is due to spring desiccation and not to actual winterkilling.

“Wheat is by far the most valuable plant in the world. It is the main source of food for modern Europe, for much of Asia for America and Australasia. In view of its importance it is strange that there should be no record of its discovery.” In the words of M. Henri Fabre, “History...... celebrates the battlefields whereon we meet our death, but scorns to speak of the ploughed fields whereby we thrive .... it cannot tell us the origin of wheat.” Since the World War the centres of production of wheat have been changed. Prior to 1914 Europe produced about 50 per cent of the World’s wheat and consumed about 60 per cent. European production was centred in districts such as the Ukraine, which are now largely disorganised. Russia, once the chief exporter of wheat, has yet to recommence exporting on a large scale, of the European countries France and Italy alone have regained their pre-war production. North America is now the chief exporting country and has made up the shortage created by the collapse in Europe. Although not realised as yet, the possibilities of development in Asia are enormous. The world production of wheat in 1922 was 3,392 million bushels. At an average price of 4/6 per bushel this production would be worth £763,000,000. This emphasises the importance of the wheat crop and justifies “the large amount of money that is spent annually in all classes of work, experimental, educational and otherwise, aimed at securing maximum wheat production at the minimum cost.

1. There appeared to be no advantages from premature harvesting of rust-infected wheat or oats. The yield of Marquis wheat and Victory oats increased from the time the grain was in the milk stage until shortly before maturity. Kernel development failed only when senescence had set in with resulting disintegration of chlorophyll and tissue dessication. 2. Grain quality, as measured by increased weight per bushel and 1,000-kernel weight, was greater when plants were permitted to mature before harvest. Premature cutting, until about six days before maturity, resulted in lowered grain weight in both wheat and oats. 3. The grade of wheat was not increased with approach of maturity, even though the percentage of dark, hard, and vitreous kernels increased to a point near maturity. The bushel weight of both wheat and oats was low enough to cause all grain to be designated as "Sample Grade." 4. No recognizable differences in 1,000-kernel weight were noted for grain from plants dried in the oven immediately upon harvest, dried in shock in regular manner, in shock with culm bases in water, and in bags under the eaves of a building. 5. There were no differences in 1,000-kernel weight of grains attached to the full-length plant as contrasted with seed from severed spikelets. 6. Apparently, transfer of material from the plant to the seed after harvest was too small to appear in increased kernel weight. Both wheat and oats gave increased percentages of dry matter with maturity. With the exception of glumes and grain, this was largely the result of water loss. In glumes and grain the actual dry matter increased. 7. Nitrogen percentage of both wheat and oats decreased slightly with maturity. 8. Nearly mature to mature wheat was decidedly superior in milling and baking value. This was especially true of loaf color. 9. In both crops, straw yields tended to decrease, while grain yields increased as the plants matured. 10. Life action probably continues for some time after harvest as evidenced by the wheat caryopses changing from green to red when left within the glumes but remaining green when dried in an oven. 11. There were no changes in internodal length from the milk stage to maturity. 12. Evaporation of water from plants as measured by the atmometer was greater in shocks built from more mature plants. 13. The percentage of oat hull (lemma and palea) decreased with kernel development during successive harvests. 14. On the basis of these and earlier results, there appears to be no more justification for premature harvest during rust epidemics than during years when no epidemic is present.

In studies on the reaction of varieties of wheat to leaf rust, P. triticina, p. f. 9, in the greenhouse at Manhattan, Kan., 28 out of about 200 varieties were found to contain resistant strains. With but few exceptions the resistant strains resembled the varieties from which they came in their general morphological characters. Some of them varied slightly from the parent varieties in one or more characters, such as kernel texture. Most of the varieties in which resistant strains were found are soft red winter wheats. These studies have shown that selection within varieties of wheat is a useful method of quickly securing strains which are resistant to a single physiologic form of leaf rust.

1. At the Kansas Experiment Station soil moisture determinations to a depth of 10 feet have been made during the seasons of 1926 to 1928 on upland that has been in alfalfa since 1910 and also on land in a 16-year rotation including 4 years of alfalfa. 2. When alfalfa was on the land the moisture content of the deep subsoil was reduced to a low point and remained almost constant. 3. With most of the rainfall coming during the growing season, the moisture penetrated very slightly below a depth of 6 feet. The crop used the moisture about as fast as it came. 4. When alfalfa land in the 16-year rotation was broken and kept in corn and wheat for 10 years, the deep subsoil failed to gain materially in moisture. 5. When a field in alfalfa for 18 years was broken out June 6, 1928, and fallowed until August, both the soil and the deep subsoil gained rapidly in moisture, whereas other land carrying a crop made no gain during this period. This would tend to emphasize the value of at least a short period of fallowing to conserve moisture for getting alfalfa started.

The bulked-population method of handling cereal hybrids consists essentially of creating populations by hybridization, growing the hybrids in bulk for six or eight generations until they have become homozygous or nearly so, and then making head or plant selections for comparative testing in the usual way. Nineteen crosses were handled by this method in an experiment at University Farm, Davis, Calif., in all or part of the years from 1923 to 1926, inclusive. Two generations were grown in each year. Head selections were made in 1926 and were grown in head rows in 1927. The best head rows were sown in replicated 16-foot triple rows in 1928. The average yields of 33 of the 45 selections grown in 1928, or 73.3% of the total number, were above the average yield of all (33) check rows. As a group the selections showed marked resistance to lodging and shattering. Hard-kerneled types predominated. The number of generations required before selection depends on the number of character differences involved. Ordinarily, seven or eight generations are sufficient. The area used for a bulk population should be large enough so that, at the rate of seeding employed, all combinations expected in a cross maybe included. On the average, wheat contains 10,500 kernels per pound. From 1 to 2 pounds should be sown when dealing with crosses of ordinary complexity. The method is adapted for the development of strains possessing such characters as winterhardiness, rust resistance, smut resistance, etc., in the close-fertilized cereals.

1. Changes in the composition of the crown of the wheat seedling were studied during two consecutive winter seasons, 1923-24 and 1924-25. Plants were taken from three dates of seeding test plats. Seedings were made on or close to the following dates: August 15, August 31, September 21, October 6, and October 19. The order of mortality due to winterkilling, from high to low, for three years, 1922 to 1925, was as follows: October 19, October 6, August 12, August 31, and September 21. 2. In general there seemed to be a positive correlation between the total soluble carbohydrate compounds and better dates of seeding or winterhardiness for the year 1923. The September 21 seeding, the best date of seeding, showed in 1923, particularly, the greatest percentage of total sugars as well as total carbohydrate compounds. However, for the two years' results, winterhardiness could not be attributed to the hexose carbohydrate compounds alone. 3. The total nitrogen compounds remained about the same throughout the winter months, being somewhat higher in the young plants than in the older plants. 4. The water-soluble nitrogen and soluble nitrogen which is coagulable by heat increased during the fall months as the temperature decreased. The soluble nitrogen which is coagulable was found to increase with the lowering of the temperature to the freezing point after which it greatly decreased. 5. The percentage of water-soluble nitrogen which is coagulable was greatest for the favorable dates of seeding, before the plants were frozen, but after freezing occurred the coagulable nitrogen was much less for plants from the favorable than from the unfavorable seedings. 6. The plants from the most favorable dates of seeding have a greater capacity of changing the protein nitrogen from a precipitable to a nonprecipitable form.