the relative susceptibility of different stocks, 20 plants each of 12 other varieties were planted in sterilized soil and then inoculated with the nematode.

The roots affected with nematodes almost always show also a growth of fungus mycelium, probably a species of Fusarium. The relation of this fungus to the nematode and to the damage of the trees is also being studied in the field and in a special series of pot cultures.

The relation of the nematode to Mottle Leaf has not yet been demonstrated, but the experiments under way should within the next year give fairly conclusive evidence on this point.

A Study of the Relative Influence of Different Factors on the Composition of Certain Fruits and Nuts.-During the year analyses have been made by Mr. H. D. Young of Navel oranges from the different plots in the fertilizer experiments at the Riverside Station. These plots furnish an excellent opportunity to discover whether or not it is possible to affect the quality of the fruit by changing the fertilizer applied, since in the twenty plots nearly every combination of the usual fertilizers is found. From this, the first year's work, it seems that the effect on the recognizable qualities, such as sweetness and acidity, is very slight. However, although the fruits from the individual trees showed great variation, the average of the plots receiving potash alone showed the fruit to be a little sweeter than that from the other plots. Of the plots receiving only one of the usual elements of fertility, the phosphoric acid plots ranked second in sweetness, the nitrogen plots, third. One of the most striking things shown was that the juice of the fruit from the plots receiving nitrogen in any form, uniformly showed a higher per cent of nitrogen.

The possible relation of the rootstock on the fruit has also been under investigation chemically. Navel oranges grown on sweet stock were found to have more sugar and less acid than those grown on sour stock. Fruit from trifoliata stock had less of both sugar and acid than either of the others. It also produced a slightly firmer fruit. The continuation of this investigation for several years should give conclusions of considerable value.

A Study of the Freeze of January, 1913.-A study and observation on the effect of the freeze of the winter of 1913 has been continued during the year. While the principal portion of the work was concluded by the fall of 1913, the publication of the studies has been delayed to await the full recovery of the groves under observation. With the fine growth thrown out by the trees all over the state this spring, the recovery may be said to be complete and the results of the study will now be tabulated and published as early as possible.

A picnic is held annually at the University Farm.

AGRICULTURAL CHEMISTRY

BY

JOHN S. BURD

Fertilizer Control.-The Fertilizer Control work, consisting of the inspection of fertilizers found on the market throughout the state, together with samples received from consumers, has continued as usual, and about six hundred samples of such materials have been analyzed in the laboratory. Experience has shown that examinations of approximately this number are sufficient to maintain on a high basis the standards under which fertilizers are being sold.

Examination of Water.-During the year the service rendered in the matter of examination of water supplies has been entirely reorganized and the attempt has been made to make it more useful. Owing to technical questions in connection with the interpretation of the results of water analyses and to the lack of information on the part of the public with regard to same, it is difficult to render the maximum service without undue waste of time on the part of members of the staff. On this account it is undesirable in many cases to make complete analyses as frequently requested by our correspondents. It has, therefore, been determined to inaugurate the system of making partial analyses which shall be as comprehensive as is justified by the character of the sample submitted, reserving the complete analyses for those waters whose properties would otherwise be in doubt. The total number of complete analyses which will have been made approximates one hundred and seventy-five, in addition to about fifty samples upon which a partial analysis has been made. In connection with these water analyses it has been possible frequently to condemn waters which were unsuitable for specific purposes and to give warnings and advice with regard to the utilization of other supplies.

Research. Three projects have been inaugurated during the year to which all of the members of the staff have devoted considerable of their time, Professor Stewart's time being exclusively devoted to this work. These projects are:

Investigation of the Moisture Content and Fertilizing Value of the Principal Kelps Found on the Coast of California.

Investigation of the Nature and Commercial Value of the Proximate Principles and Distillation Derivatives Present in the Principal Constituents of Kelp-Nitrogen and Potash.

Investigation of the Agricultural Value of the Major Fertilizing Varieties of California Kelp.

These projects comprise the various phases of a comprehensive study of the agricultural and commercial utilization of kelp and have indicated the possibilities and limitations of this material in the above

connections.

AGRICULTURAL EDUCATION

BY

W. G. HUMMEL

The instructional work of the division has included the giving of courses in agricultural teaching methods at the University during the summer session of 1913 and during both semesters of the 19131914 college year. It has also included the conduct of correspondence courses in agriculture prepared by members of the faculty of the College of Agriculture.

Correspondence Courses in Agriculture.-In September, 1913, the first four correspondence courses in agriculture were ready for students. Eleven are now completed. Twenty-one other courses have been announced as in preparation.

The courses now ready for students are as follows:

The first correspondence course lesson was sent out September 18, 1913. From that time up to April 30, 1914, 31,605 lessons have been sent out.

The present (April 30, 1914) enrolment in agricultural correspondence courses ready for students is 6743. Of this number 5986 are taking their first course; 599 are re-enrolments. Two hundred and forty-seven students are taking their second course; 28 a third course; 4 a fourth course; and 1 a fifth course. One hundred and fifty-eight students have completed one course, but have not enrolled in another