Mr. SANDLIN. What is the main cause of the decaying of potatoes? Is it the bruising of them?

Mr. MCCRORY. There is a variety of causes. I am not a potato specialist, but part of it is due to injuries in digging and handling, and part is due to certain organisms that grow during storage. A proper temperature control helps to control the difficulty, and then if you can avoid damaging the potatoes in digging and storing, you can eliminate much of the loss.

Mr. SANDLIN. The problem that you are interested in is the storage and the regulation of the heat?

Mr. MCCRORY. We have been able to do a good deal in that territory by showing farmers how to improve the insulation of their buildings and how to regulate their heat so that they do not get some parts of the building too hot and others too cold.

Mr. SINCLAIR. Do you pretend to say at what temperature a warehouse or storage house should be kept?

Mr. MCCRORY. We have obtained a good deal of information by varying the temperatures in the warehouses as to what are the best. temperatures. We have been interested in that problem. We got into it first on sweetpotatoes, and we worked for 2 years on the eastern shore of Virginia in a sweetpotato house and worked out a good deal of information in regard to the temperatures.

Mr. SINCLAIR. Do you care to state what that temperature is? Mr. MCCRORY. Apparently the most desirable temperature for potatoes in storage is 40° F. Sweetpotatoes should be cured at 85° and then held at 55°.

Mr. SANDLIN. Have any bulletins been gotten out on this subject? Mr. MCCRORY. On the sweetpotato work; yes, sir. The Maine work has not yet been published. The storage losses have been reduced from about 20 percent to about 5 percent in the houses in which we are working.

Mr. SANDLIN. That is very interesting.

DESIGN OF LOW-COST FARM HOUSES

Mr. MCCRORY. Another job to which we have been giving a good deal of attention recently, in connection with a Civil Works project, has been the design of low-cost farm houses. One of the interesting developments at the present time is the considerable increase in the number of requests that are coming for information in regard to houses that can be built cheaply. We have been giving a good deal of study to that problem, and recently this Civil Works project on farm housing has afforded an opportunity to expand that work. We are developing houses that can be built for from $500 upward in the South, and from $750 upward in the North, which we think will be quite usable.

FARM MECHANICAL EQUIPMENT

The activities of the Mechanical Equipment Division deal primarily with farm power and machinery and equipment.

The current investigations consist of: (1) Analytical studies of methods and machinery for the production of various crops with the ultimate object of finding the most economical and advantageous application of labor, power, and machinery; (2) the adaptation and

development of equipment for the effective and economic control of important crop pests and plant diseases; (3) fertilizer placement studies involving the adaptation or design of machinery which will deposit fertilizer at a given place, with respect to the seed, for maximum yield of various crops; (4) critical studies of factors involved in the artificial drying of forage crops, applicable to the humid regions, with a view to working out lower cost methods and equipment than now exist.

CORN PRODUCTION

On the corn-production project at Ames, Iowa, a furrow-damming attachment for a lister-planter was developed. This device causes dams to be thrown across the listed furrow periodically, thereby minimizing soil washing and causing a more uniform distribution and retention of the rain water. "Pay-out" planter check wire stakes have been developed so that it is now possible to accurately plant corn with a tractor 4-row planter-the maximum variation from a perfect check being about 11⁄2 inches.

Picker-loss tests made with several commercial mechanical pickers on different varieties of corn varied from 2.48 to 11.87 bushels per acre. Timeliness tests and other picker tests are still under way. The plan of work the coming year will be approximately as follows: (1) Studies of labor, power, and machinery expenditures used in growing corn by several different methods; (2) comparison of different methods of preparing seed bed, planting, and cultivating; (3) comparison of three methods of growing corn; (4) corn-picker performance studies; and (5) improvement of corn-production machinery-intended to supplement but not to compete with the commercial development of machinery.

COTTON PRODUCTION

A public patent was obtained on a variable-depth cotton planter. By the use of this tool the probability of producing a normal stand of cotton is greatly increased over the use of a constant depth planter. Tests the past season show a higher average yield with the variable depth.

A pivot axle-frame unit has been devised which permits the attaching thereto of (1) a seed-bed preparation bedding unit, (2) variabledepth cotton planter and fertilizer attachment and cultivator equipment of six different types. This should be instrumental in minimizing the farmer's outlay for equipment.

Studies of ways and means of reducing the cost of producing cotton in the Southeast are to be continued next year. To supplement this project, a farm tillage-machinery laboratory is to be built as soon as the plans are completed, where by it will be possible to study on a field scale the relationship of various plow and tillage implement designs to the dozen different soil types, the physical effects on the soils, and other factors.

SUGAR-BEET MACHINERY

A successful mechanical cross blocker has been worked out which not only effects a considerable saving in labor but also permits of blocking a whole field at the time most desirable for the crop. U.S.D.A. Leaflet No. 97 covering the subject has just been published.

For the purpose of more uniform planting and minimizing labor requirement for cross blocking and thinning, a hill planter has been developed. This can be used as a single-row planter or incorporated into multiple-row beet drills. Application has been made for a public patent on the device. A crust-breaking device to enable beet seedlings to come through unhindered has recently been devised.

Contact has been maintained and, to a limited extent, cooperation given to beet-harvester manufacturers.

A 10-acre plot has been planted to beets the past year and experimental work with machinery conducted thereon. This has permitted the following out of a well-organized plan of work without interference. It is proposed the next season to continue encouraging the development of beet harvesters as well as to continue critical studies of the important machines and methods used in the production of this crop.

CORN BORER CONTROL

Investigations dealing with the clean plowing-under of crop refuse have been continued. A public patent has recently been granted on a trash guide plow attachment, which when properly installed effects almost complete coverage of stalks. With certain modifications it can be installed on walking or wheel plows, cutting 12-inch furrows or larger.

A disc jointer to replace the conventional mold-board jointer has been devised, particularly for soils in which scouring difficulties are encountered. Preliminary trials show a decrease in draft of about 10 percent when compared with a plow equipped with a standard coulter and jointer.

Development work on the corn picker with chopping-box attachment has been continued in a limited way. This machine is designed to not only pick corn with as little field loss as possible but also to chop up the stalks and kill the borers, and deposit the chopped fodder back on the land to maintain the humus in the soil.

The development of a 1-row low-cutting sled harvester has been practically completed. This device is inexpensive to construct and should be useful where the cost of a binder is not justified or its use impracticable.

Some work has been done on a sprayer to combat the pest in sweet corn, where the net return warrants this extra expense.

PINK BOLLWORM

It has been found in the cultural experiments extending over four years that if plowing can be followed by immediate irrigation the plowing and irrigating may be done at any date with equal and most effective results. If plowing must be done in December or January in order to allow planting of a winter crop, it should be irrigated within 1 week.

Extensive tests with a 14-inch moldboard plow show that deep plowing is more effective in control than shallow, and that a 14-inch plow is more effective than a disc plow or 10- or 12-inch moldboard plow. Complete mortality of pink boll worm larvae occurred when calcium cyanide or paradichlorbenzene was introduced into the furrow in plowing under infested cotton bolls.

A push type stalk shaver for use preparatory to raking and burning has given excellent results in one season's tests.

JAPANESE BEETLE GRUB

In New Jersey a number of tests have been run with various types of rotary plow in an effort to produce effective execution of Japanese beetle larvae. One make of rotary plow was purchased on which a number of changes have been made and the effectiveness increased. Further work is to be done and other machines and ideas tried out as conditions warrant. Equipment effective for controling the above insect will also be effective in combating the wire worm and white grub.

PECAN DUSTING

Tests of spray equipment, including nozzles and guns have been made with a view ot discovering points in need of improvement for better performance. Corrosion and erosion tests on various promising alloys are being conducted on nozzle discs and pump plungers with a view to prolonging the useful life of the parts exposed to the spray solutions. A new type gun cut-off gives considerable promise.

FERTILIZER DISTRIBUTING MACHINERY

Field studies on the placement of fertilizer for beans, cotton, potatoes, sugar beets, and tobacco were conducted at 34 locations in 17 States during the past season for the purpose of obtaining fundamental information upon which might be based improved designs of fertilizer distributing machinery. Results of these studies indicate that fertilizer placed too near the seed injured germination and retarded early plant growth, and if placed too far away the fertilizer did not stimulate early plant growth. The extent to which each crop was affected depended upon type of soil, amount and placement of fertilizer, rainfall, temperature, and possibly other factors.

In the laboratory and shop, improvements to obtain the most accurate control possible under varying conditions were made on the experimental fertilizer distributors and planters which now include 3 for cotton, 2 for potatoes, 2 for beans, 1 for tobacco, 1 for sugar beets, and 1 side dressing machine.

Improved placement and more economical use of fertilizers in commercial machines is resulting from this work.

ARTIFICIAL DRYING OF CROPS

Investigations on various and sundry driers have been concluded and data assembled which show the limitations of present installations. The rotary drum drier which, when installed, received the forage to be dried at one end and discharged it at the other end, has been reconstructed into a return type wherein the forage passes in through a central drum and returns through the outside annular portion, thereby better utilizing the heat.

Tests with heated crushing rolls indicated that more effective drying could be done by applying the heat under the metal conveyor just before it passes around the drum. By the heated metal thus being in contact with the forage for a longer time, more effective drying should be accomplished.

By directing the heated air currents for more effective use, the overall efficiency of the apron drier has been increased some 10 percent. A further increase appears possible.

Studies of effectiveness and practicability are to be made of a return tower drier which is soon to be built.

The efforts are centered mainly on reducing the cost of the drying operations consistent with maintaining a good quality product.

MISCELLANEOUS

The following miscellaneous investigations were made:

1. Effect of temperature and humidity on the moisture content and keeping quality of corn, flaxseed, oats, rice, soybeans, sorghum, wheat, cotton, and alfalfa hay, fundamental to investigations dealing with drying agricultural products. These tests have been completed. 2. Devising a low-cost method of hulling and scarifying legume seed for the purpose of accelerating germination. To date a tumbling barrel using gravel appears to be the most satisfactory as well as most economical for the farmers' use.

3. Methods of removal of smut balls for wheat have been studied. A series of tests were run in St. Paul last winter on commercial machines. Three small ones of the most promising types have been purchased for carrying on further investigations with a view to improving or constructing a new machine incorporating good features from the above machines.

4. A practical test of the use of alcohol gasoline fuel blends was started at Toledo, Ohio, in November 1932, and is still in progress. The automobiles, tractors, and trucks were used on routine work. There appears to be no outstanding difference in favor of either the plain gasoline or the 10 percent alcohol blend. The results to date for the automobiles and trucks are shown in the following tabulation:

STUDY OF PROBLEMS INVOLVED IN GROWING SUGAR BEETS

There are two investigations that the committee might be especially interested in. One is a study of the problems involved in growing sugar beets. We feel that considerable progress has been made in developing methods of cross-blocking and harvesting sugar beets. Also we are working on the problem of improved methods of fertilizing sugar beets by the use of machines which will place the fertilizer