T A é “Q, éA304-1019-101T4 TEXAS AGRICUL URAL EXPERIMENT STATION f AGRICULTURAL AND MECHANICAL COLLEGE OF TEXAS W. B. BIZZELL, President BULLETIN NO. 250 OCTOBER, 1919 ‘r EXPERIMENT STATION ANDSEXTENSION SERVICE COOPERATING STORAGE AND DISEASES OF THE SWEET POTATO IN TEXAS B. YOUNGBLOOD, DIRECTOR College Station, Brazos County, Texas STATION STAFFT ADMINISTRATION B. YOUNGBLOOD, M. S.,_ Director A. B. CONNER, B. S., Vice Director J. M Jomzs, A. M., Assistant Director CHAS. A. FELKER, Chief Clerk A. S. WARE, Secretary _ —i————. Executive Assistant CHARLES SOSOLIK, Technical Assistant VETERINARY SCIENCE *M. FRANcis, D. V. M., Chief _ H. Scmmrr, D. V. S., VCICNRGIIGH I D. H. BENNETT, V. M. D., Veterinarian CHEMISTRY I O A G. S. Farms, Ph. D., Chief; State Chemist E. Asaumi, M. S., Assistant Chemist ’ , LOMANITZ, B. S.. Assistant Chemist _ ’ B SQHILLING, B. S., Assistant _Chemist . E. Eyer, B. S., Assistant Chemist RTICULTURE _ . NESS. M. S., Chief . S. HOTCHKISS. Horticulturist a; rim/am ENTOMOLOGY ' p’ M. C. TANQUARY, Ph. D., Chief, State B molnaisl v H. J REINHARD, B. S., Entomologist . W. E. JACKSON, M. S.. Assistant Entomo i _ AGRONOMY A B. Cowman, B. S., Chief A. H. LEIDIGH, B. S., Agronomist E. W. GEYER. B. S., Agronomist H. H. LAUDE, M. S., Agronomist PLANT PATHOLOGY AND PHYSIOLOG J. J. TAUBENHAUS, Ph. D., Chief i’ FEED CONTROL SERVICE F. D. FULLER, M. S., Chief J AMES SuLLivAn, Executive Secretary FORESTRY E. O. SIECKE‘, M. F., ChiefLState Forester PLANT BREEDING NIMAL INDUSTRY E. P. HUMBERT, Ph. D., Chief J. IM- JONES. A. M., Chief; Sheep and Goat nvestigati ns. . C. Bumis, B. S., Animal Husbandman in FARM AND RANCH ECQNOMICS J Charge of Beef Cattle Investigations (on leave) H‘ M‘ ELIOT’ M' A" Chief .B McNuLTY, B S., Dairuman R. M. Sir RWOOD, B. S., Poiiltryman SOIL SURVEY ———;>——— , Animal Husbandman in **W. T. CARTER. JR., B. S., Chief Charoe of Swine Investigations J. F. Srnouo, Soil Surveyor nawsn, B. S., Assistant Animal Hus- T. M BUSHNELL. B. S.. Soil Simian/r . bandman W. B. Fn \NCIS, B. S., SoilSurveyor SUBSTATIONS No. 1. Beeville, Bee County No. 8. Lubbock, Lubbock County . I. E. COWART, M. S., Superintendent R. E. KARPER, S_., Superintendent D. L. Jones, Scientific Assistant ' No.2. Troup, Smith County No 9 Pecos Reeves Count - . . , y . W‘ S’ HOTCHKISS‘ Supermtendem J. W. Jackson, B. S., Superintendent N°- 3- Anglemnv Bmmria 0mm‘? No l0 (Feeding and Breeding Substatle E. B. REYNOLDS, M. S., Superintendent ' bone“ Station, Brazos Co t, ' J. W. LUKFR, B._S., Superinteriliilent , No. 4. Beaumont, Jefferson County L. IscHY, Scientific Assistant ~ A. H. PRINCE, B. S., Superintendent No- n. Nacogdoches, Ngcogdoches Cum” .5 _ N.“ 5_ Temp“, Be“ County G. T. McNizss, Superintendent ' D- T- KII-I-mmfi» B- 5» S"P¢"'""="d"" **No. 12. Chillicothe, Hardeman County A B Cnou B. S Superintendent 1N0- 6- Demen- Denw" 60'1"” . v' 12'. iilpiéim B s Scientific Assist C. H. McDovi ELL, B. S., Superintendent ' ’ ' " __ N 1 s 0' k c t NOJEMIQI gonora’ Bsuétolis-Edwgrzdsdciunfl A l o. . pur, ic ens oun y . . mans, .. uperin en en R. E. DICKSON, B. S., Superintendent G. R. WARREN, B. S., Shepherd TAs of October 15, 1919. IIn cooperation wi_th School of Agriculture, A. & M. College of Texas. *In cooperation with the School of Veterinary Medicine, A if: M. College of Texas. "In cooperation with the United States Department of Agriculture. FOREWORD. Sweet potato storage is a comparatively new industry in Texas. Dur- ing the past few years, however, a great deal of interest has been mani- fested in improved methods of storage and this industry is LOW develop- ing rapidly". ‘ _ Before storage houses came into use, the sweet potato crop was un- profitable, except on a small scale. The old style “banking” of potatoes proved unsatisfactory and was practical only in a small way. Because of improper storage facilities, potatoes had to be marketed in the fall at harvesting time, a practice which resulted in the glutting of the markets, and consequently in low prices. But with efficient storage houses the period during which sweet potatoes can be marketed will be greatly ex- tended. The prices paid for them will be stabilized. As the number of storage houses increases, the sweet potato will become one of the big staple crops of Texas. Extensive studies have been made in sweet potato storage by a com- mittee composed of the following members of the Texas Agricultural Experiment Station and Extension Service staffs: J. J. Taubenhaus, Plant Pathologist, Experiment Station. E. A. Miller, Sweet Potato Storage Specialist, Extension Service. H. M. Eliot, fFarm and Ranch Economist, Experiment Station. B. F. Brown, Rural Economist, Extension Service. A. K. Short, Agronomist, Extension Service. As a result of their studies and from data collected on this impor- tant subject, the Texas A. and M. storage house, which is described in this bulletin, was developed. This type of house has been given a severe test under adverse conditions, and has proved very satisfactory. It is relatively low in cost of construction; it is cheaply' and simply operated; it keeps potatoes with a minimum loss from rots; and it gives them good shipping qualities. The committee strongly recommends this type of house to the people of Texas. B. YOUNGBLOOD, Director of Texas Agricultural Experiment Station. [Blank Page in Griginal Bulletin] STORAGE AND DISEASES OF THE SWEET POTATO 1N TEXAS DESCRIPTION OF THE HOUSE. UNIT HOUSE. The house here presented is a 5000-bushel house and is designed as a unit system. A comparatively small unit has been chosen because the large unit houses (capacity 10,000 to 100,000 bushels) makes suc- cessful storage much more difficult. Tn such houses the losses from rots are often very heavy. The 5000-bushel unit house is advocated because i11 that unit of bulk it is possible to make use of all the natural conditions of ventilation, and, with proper management, to reduce the losses from rots to a minimum. Where a storage capacity of 10,000 bushels is desired, two units of 5000 bushels each may be used. These can either be built separately, or the building made twice as long. In the latter case the cost of one end wall is saved and the separating wall can be built more cheaply as the only material then needed is a layer of building paper and shiplap on each side of the studding instead of two layers of shiplap. This same arrangement can also be carried out with the larger bulks of 15,000 bushels and over. Where the houses cannot be built end to end they should be separated altogether and a space of not less tha twenty feet should be left between them. The dimensions of the 50 - ushel house are 59 feet ten inches by 26 feet by 11 feet four inches. The prepon- derance of length (Figs. 1, 13, 1-1, 15) is designed to secure the maxi- mum amount of ventilation. FRAME BUI LDING. The Texas A. and M’. 5000-bushel unit house is built of lumber (Fig. 1), for the reason that this material has been thoroughly tested out and has given satisfaction. Moreover, it is the easiest building material to secure and the average carpenter can easily handle it. The house is constructed on piers, which extend about two feet above ground (Figs. 1, 14, 15, 18, 22). This arrangement allows the necessary floor ven- tilation, which is a distinct feature of this type of house. To protect the house against severe cold spells, outer drop-doors on the north and west sides reaching from the baseboard to the ground are desirable. These are raised or lowered as the weather conditions demand. They are, however, merely an extra precaution against the “northers” which sometimes occur in certan parts of Texas. For further details of the construction of the house see Fig. 1. VENTILATORS. The arrangements of floor ventilators (Figs. 5, 9, 33, 36, 37), windows (Figs. 1, 14, 15, 31), doors (Figs. 1., 15, 31), and-ceiling ventilators 6 TEXAS AGRICULTURAL EXPERIMENT STATION. (Figs. 1, 14, 15, 16) are distinct features of the house. Any or all of these ventilators may be opened or closed When it is necessary to admit or exclude air currents. CUPOLA. The cupola (Figs. 1., 14, 15) solves the roof ventilation problem by offering a large free opening for the escape of moisture-laden, or hot air, and at the same time by its construction protecting the interior of the building from rain or snow. The o, ening into the eupola is con- trolled by means of doors in the ceiling of the house (Fig. 16). FLUE AND STOVE. Another distinct and important feature of this house is the method of heating and air circulation, Which Is accomplished by means of a stove and flue (Figs. 12, 15, 20, 33). This is really an adaptation from the mo-dern system of heating schoolhouses. The features of this sys- tem of heating is an opening under the stove, through which the out- door air enters from under the house. The air then passes around a jacketed stove, where it, becomes heated and dried in contact with the stove. Since warm air is lighter, it Will naturally rise to the ceiling and spread to all parts of the house. As it absorbs moisture from the in- side air, it becomes cooler and heavier and falls to the floor, whence it escapes by suction through the bottom openings of the flue. By this method a constant and strong circulation of Warm dry air may be main- tained Whenever damp or cold Weather makes it necessary to keep win- dows and ventilators closed. BIN CONSTRUCTION. The bins are divided into four quarters (Figs 2, 21 to 27, 30, 32), two above and two below. This division causes the potatoes to be in small bulk and thus facilitates the curing process. The bins are also A raised above the floor so as to allow circulation of air from underneath. Where it is not desired to store in bins the same house may be utilized for storing in hampers (Figs. 10 and 11), baskets or crates. For this purpose slatted platforms covering the same floor space as the bins may be built (Fig. 35), upon Which the containers are placed. Where the bins are left out the cost of the house is considerably reduced. Another advantage of storing in containers in place of bins is that after the potatoes have been shipped, the empty house can be more conveniently utilized for other purposes. Still another advantage of storing in ham- pers is in the saving of unnecessary handling, thereby reducing the chances of bruising. Furthermore, each hamper or container is really a miniature bin containing a minimum of bulk, and receiving a maxi- mum amount of ventilation. LOADING PLATFORM. In connection with the outside of the house there is a loading plat- form (Figs. 3, 14). This is built to facilitate the unloading of the STORAGE AND DISEASES OF THE SWEET POTATO IN TEXAS. 7 potatoes from the wagon into the house, or in taking the potatoes from the house for shipment. BILLS OF MATERIAL FOR THE TEXAS A. AND M. SWEET POTATO HOUSE. HOUSE ONLY Material Size Required Piers .......................................................................................... .. As detailed.. 40 Platform Posts ........................................................................ .. As detailed.. 8 Chimney Base ........................................................................ .. As detailed. 1 Sills, Fl0or—— 6" x 12" .............................................................................................. .. 120 Ft. 9" x 12" ........................................................... .. . .............................. .. 180 Ft. Joists, Floor—— 3" x 12" .......................................................................... .. 14’——0" 55 Wall Stops—- 2" x 4" ................................................................... ..~ ....... .. 22’—0” 70 Cupola Studs—— 2" x 4" ............................................................................ .. 16’—0" 12 Plate, Wall- ’ x 4”....- ........................................................................ .. 16’——0” 24 Plate, Cupola—— 2" x 4" ............................................................................ .. 10’—0” 12 Joists, Ceiling- 2" x 4" ............................................................................ .. 14’——O” 3O ‘fies, Overhead—-— 2" x 4" ............................................................................ .. 16’——0” 30 Rafters, H ——— 2" x ............................................................................ .. 18’—0" 64 Rafters, Cupola—— _ 2" x ' ............................................................................ .. 16’——-0” 12 Sh1plap—— Floo .................................................................................................. .., ........... .. 3500 Ceiling .............................................................................................................. .. 3600 Walls, Inside .................................................................................................... .. 4800 Walls, Outside ................................................................................................. .. 2800 Roof .................................................................................................................. .. 400 Building Paper ........................................................................................................ .. 1600 Yds ,Drop Siding ........................................................................... .. N0. 117 ................ .. 00 Shipla .................................................................................... .. Siding .................... .. 1”x 10 feet ...................................................................................................... .. 1100 Con. Window Sill—- 2" x 6" ............................................................................ .. 16’—0" 12 Shingles .................................................................................................................... .. 16,000 Windows- 4 ht .............................................................................. .. _ 15" x 30" _ 1 3-8 Check ...................................................................... .. Rail and lock ...... .. 16 Gable Sash—— 4 light .............................................................................. .. 10" x 12" 2 Sash Weight ........................................................................... ............................... .. 32 Common Brick ........................................................................................................ .. 4500 Heater—— Strap Hinges .............................................. ..- ............................ .. ’ 200 Pulleys ................................................................................... .. 6 Rope ........................................................................................ .. 100 Ft. Paint ........................................................................................ .. 2 Coats Nails._ ....................................................................................... .. 400 Lbs. Bridg1ng— 1" x 4" ....................................................... ................... .. 640 Ft. Loading Platf0rm—— 4" x 10" ...................................................... .. 2 2" x 6". ................................................ .. . _ 40 Steps ..................................................................................... .. . See detail ............ .. 8 TEXAS AGRICULTURAL EXPERIMENT STATION. BIN STORAGE Material Size Studding— 2" x 6" ............................................................................ .. 16’—0” 2" x 6" ............................................................................ .. 12’—O" Bi'n éoistsé-l 16,_0” _ x ............................................................................ .. " Slats— 1" x 6" ............................................................................ .. l6’—0" Spacers— 2" x 4" ............................................................................ .. 16’—-—0” 1" x 2"‘. ........................................................................... .. 16’_—0” Shiplap— Stove A1s1e—— 1" x 6" ......................................................................... .. 16'—O” Nil-l ....................... .; ............................................................................................... .. Hirigses ...................................................................................... .. 6" HAMPERS, BASKETS OR CRATE STORAGE Material Size Required Posts nlgarked P _ on ans 2" x 6" ............................................................................ .. 12’—O" _ 4O slats; 4 16' o" 200 x ” ........................................................................... .. — Platform— Joists—— 2" x 8" ........................................... .._ ............................. .. 16'—O” 25 Nails—— » Uridging....._ ............................................................................ x 1" x 4" 400 Ft. PREPARING THE HOUSE FOR STORAGE. Some time before harvesting and during any slack time in the sum mer, the house should be carefully overhauled and any necessary repai '~ made. Broken windows should. be- replaced and all doors, ventilato’ and other outside openings made to fit tight. Any leaks in the r00 should be repaired and all rat holes closed. If the bins need repai they should also receive attention. The stove and stove pipe should b overhauled and cleaned. The house should also receive a thorough cleaning so as to remov all the dust and refuse left over from the previous crop. The indoo Walls and woodwork, as Well. as the floor, should be rlisinfected by spray ing With a solution of concentrated lime sulphur. To make this, mix’ 15 pounds of sulphur and '72} pounds of stone (unslacked) lime in sufli- cient hot Water to slake the lime. When slaked, add to a barrel of. water. One barrel of this mixture will be sufficient for the 5000-bushel house. The spraying may be done with an ordinary bucket pump hav- ing a long extension rod and an ordinary nozzle. ' If there are objections to the use of lime sulphur on account of its‘ odor, copper sulphate, also known as blue vitriol or blue stone, may be used instead. This is made in the proportion of 5 pounds of copper sulphate dissolved in a 50-gallon barrel of Water. A good Way to dis- solve the copper sulphate is to place it in a small sack and suspend it in a barrel of Water over night. Only Wooden buckets or barrels should be used, as the solution will corrode metal. Copper sulphate solution is poisonous when taken internally; hence it should not be left where children or farm animals may have access to it. STORAGE AND DISEASES or THE Swwnar POTATO IN TEXAS. 9 A more thorough method of disinfecting sweet potato houses is by the formaldehyde gas method. Unfortunately this chemical is very ex- pensive at this time, which practically prohibits its use for the present. The method is as follows: For each thousand cubic feet of storage house space buy three pints of 4.0 per cent. formaldehyde and 23 ounces of potassium permanganate. Use about three three-gallon crocks, or larger, and distribute them on the floor of the house. Then divide the permanganate and tl1e formaldehyjde separately into as many parts as there are crocks, placing the permanganate in the crooks and the for- qnaldehyde in cans or cups, one beside each crock. Close the entire house tight except a door to leave by. Then beginning with the crock farthest from the door and WOTklDg fast, pour the formaldehyde into each crock. Leave the house at once, closing the door securely behind you. As a result. of the chemical action with the permanganate, fumes will fill the house and kill all the germs, insects, rats or mice that may be present. The house should be kept closed for forty-eight hours to allow the fumes to act, after which it is opened and allowed to air. In opening, one should be careful not to inhale any of the fumes. When this method of fumigatio-n is practiced, the operation had best be per- formed by two persons so that in case of accident the other will be on hand- The burning of sulphur in the house is effective in controlling mites and in killing rats, but it will not kill the germs that cause disease on sweet potatoes. HARVESTING. A great deal of the success in storing sweet potatoes depends on the ivay in which the crop is handled in the field. Except for early market- ing, sweet potatoes should not be dug until they are well matured, as immature stock is much harder to cure and to keep. Sometimes an early frost will injure the crop, but ordinarily the season in Texas is such as to allow full maturity. It is never safe to take chances on a late frost. Where a dry summer precedes a wet fall most growers are often inclined to delay digging until too late in the season. Where this is done there is danger that the potatoes will become frost bitten in the field. If the vines are merely frosted, the potatoes are still safe for storing, but they should be dug as soon as possible. On the other hand, if the frost has killed the vines to the point of injuring the tips of the potatoes there is little chance of the crop keeping well. If "this condition arises, the potatoes should be sold immediately for early we. The natural yellowing of the foliage is usually a good indication that the potatoesare reaily to he harvested. Another test for maturity is to cut several potatoes and if the cut surfaces become white and dry in a short time the potatoes are mature; on the other hand, if the cut sur- face remains moist dIHl turns to a darker color, it is an indication that the potato is immatuirc. Furthermore, the skin of the mature potato cannot be rubbed off as easily as that of an immature one. The potatoes should he dug as carefully as possible, avoiding all un- necessaryk bruising‘. For this purpose a plow with two rolling colters attached to the beam to cut the vines, and several steel prongs on the 10 i TEXAS AGRICULTURAL EXPERIMENT STATION. mold-board to separate tho soil and the vines from the potatoes makes a very handy implement fo-r digging.‘ A “middle buster” with rolling colters also does satisfactory work. A commonmistake is made in not going deep enough. with the plow, and as a result many of the potatoes ft? are cut or bruised. The best time to dig is during, warm, dry weather, §f since the potatoes, especially the bruised ones, are more likely to rot '1 when dug while wet; besides, the potatoes dug during wet weather will ' be more Watery, and hence harder to cure. However, in wet seasons the grower will often be forced to dig when potatoes are wet and muddy. r 1. Under these conditions sweet potatoes require extra care in that they 5' must be dried quickly and the moisture not allowed to stay on the potatoes for any considerable length of time. Wet potatoes should never be stored in great bulk, but should be spread out in small quan- tities if possible. It is poor policy to dig the potatoes late in the l‘ evening and allow them to remain uncovered during the night in the 4 - field,'as they may be injured by frost or rain. Neither is it wise to dig ' early in the morning when the ground is more or less cool and the vines wet with dew. The best time to dig is after the sun is well up and not later than three or four in the afternoon, or until such a time that the grower will be able to pick up before night all that he has dug. It is not safe to allow the potatoes to remain exposed long to a hot sun, although a mild sunlight will help them to dry oif. The potatoes should be graded while being picked up. To do so will save time, labor, and" excessive ‘handling. Some of the pickers should gather the No. 1’s and others the No. 2’s, and still others the bruised, the cut, and the jumbo grades. Mechanical graders are being perfected, and no doubt they will play an important part in the future in the proper grading of sweet potatoes. Grades are described more fully j on page 1'7. _ ' ' Potatoes should be handled with extreme care and as little as pos- - sible if they are expected to keep well. Where storing is done in ham- pers, baskets or crates, it is best to gather the roots in these containers and place in the house as soon as possible. They should never be han- dled in sacks or hauled loose in a wagon box. When the potatoes are hauled from the field to the house they should be placed directly in a spring wagon and carried over the smoothest road, the aim, of course, being to avoid unnecessary shaking and jarring, which injures the potatoes. It is also necessary to fill the crates and to place the cover ii tightly on top so as to prevent jolting. If a spring wagon is not avail- able, a deep layer of straw or hay should be made in the wagon box. It is very important to prevent bruising, which is mostly caused by rough handling, because bruised potato-es are harder to keep, and even if they go through the storage period without rotting, they are prac- tically unmarketable on account of their unsightly appearance. MANAGBIDIENT OF THE POTATO HOUSE. Successful sweet potato storage depends, it is true, on the house, but intelligent management of the house is a factor which cannot be ignored. It is hoped that those who- contemplate adopting the A. and M. unit -i STORAGE AND DISEASES or THE SWEET Poraro IN TEXAS- 11 system will give it a careful study. Good management, after all, re- solves itself down to common sense. Where potatoes fail to keep, it is easy enough to throw the blame on the house, which cannot defend itself, but in many cases the fault is due to mismanagement. Enough wages should be paid to secure a first-class manager for stor- age houses. Such money is Well spent. It does not take the loss of many bushels of potatoes to amount to more than the extra salary re- QILTQO. to secure a competent manager. The Extension Service of the A. and M. College of Texas is ready to- give assistance, so far as pos- siolc, to the manager of any sweet potato house in Texas. CURING AND CARE OF SWEET POTATOES IN STORAGE. The problem of keeping sweet potatoes is the problem of preventing rot-producing fungi from growing on them. Since these destructive fui-ns of life require moisture for their development the most important factor in preventing their growth is a thoroughly dry surface. During the first ten days or two weeks of storage a great deal of moisture is given off, which generally amounts to 6 or 8 per cent. of the original weight of the sweet potatoes. This stage of greatest evaporation is called the curing period. After this, a small amount of evaporation continually goes on, but is easily handled. XYhile it is important at all times that the moisture given off by the. potatoes should be driven out of the house, it is especially important during the curing period. In the Texas A. and M. house this is easily accomplished by means of heat supplied by a stove, and through ven- tilation obtained by means of special ventilators. The heat creates air currents in the house and aids in the drying of the potatoes, for when the air that is taken in from the outside is warmed, it is given a greater cap-rcity for taking up moisture. In the A. and M. unit house the lie-it is so distributed that the temperature is practically the same in all parts of the house, except immediately under the ceiling where there are no potatoes (see chart, Fig. 34). While a certain amount of heat is essential, this requirement is often misunderstood in the sense that potato houses are frequently overheated. Warm air is not necessarily dry and it will not cure potatoes unless it is dry. After dry air has circulated around the potatoes during curing, it will be moist even though still quite warm, and must be allowed to escape with its load of moisture. The temperature during curing should run from '75 to 80 degrees Fahrenheit, and this same temperature should be maintained, as far as possible, until complete curing is indicated. The length of the curing period depends on the condition of the pota- toes. If they are grown during a season of high rainfall, and dug during wet weather, they will naturally require longer curing than those grown. during the dry season and dug when dry. Generally speaking, the curing period lasts from ten to eighteen days, two weeks being.an average. It is relatively easy to tell when potatoes are cured by merely rubbing the skin. When it clings more or less firmly and feels leathery to the touch, it indicates complete curing. On the other hand, if the skin rubs off easily the curing period should be extended. As soon as the potatoes have been cured the temperature should be 12 . TEXAS AGRICULTURAL EXPERIMENT STATION. I lowered to 55 degrees Fahrenheit. This temperature should be main-mi‘ tained as nearly as possible during the remainder of the storage period ; by using the proper judgment in opening and closing the ventilators‘ and windows. The first essential of curing sweet potatoes is to keep their surface dry. For this purpose the heating and ventilating system of the] A. and M. unit house is very eflicient. The following directions may serve as a guide during curing: While the potatoes are being brought to the house, a fire should bef kept in the stove, in order to take care of any sweating of‘ the potatoes. i‘ This is especially important; if the outside air is damp. If the weather I is dry and warm with a temperature of 75 to 80 degrees, it is not neces- f sary to keep up a fire while the house is being filled. In that case all -of the doors, windows and ventilators should be kept open. After the house has been filled, which should be within ten days to A _ two weeks, the main curing period starts. For this purpose the house f should be completely closed, except the ventilator under the stove and " the two ventilators at the bottom of the flue‘. A fire should be kept g in the stove day and night, maintaining a uniform temperature of i; 75 to 80 degrees, until the potatoes are cured, that is, until the skin feels leathery and does not peel off. By thus keeping the house closed during the curing period a large 1 volume of air is drawn in from under the house and is heated by the 1 stove; then it rises to the ceiling and spreads out evenly to all parts of the house, being drawn out through the openings in the flue. By ‘ this method a good circulation of warm air is maintained in the house i and all of the air has to circulate around the potatoes before it can escape through the flue, thereby curing all of the potatoes uniformly. (See Fig. 34, which illustrates the circulation.) In case- the weather during curing is dry and warm, having the de- y sired temperature of '75 to 80 degrees, the fire in the stove is not nec- a essary, but instead, all of the ventilators and windows can be opened, as the dry, warm air from the outside will serve exactly the same pur- pose in curing as the air heated by the stove. By consulting the ther- mometer and hygrometer the manager can easily tell when to use the g stove and when to take advantage of the outside air. The first method, that is, by keeping the house closed, works well during wet, cold, or damp Weather and the latter during warm, dry weather. If at any time the temperature rises above 80 degrees the house should be cooled by opening as many of the ceiling ventilators and those in ‘ the aisles as necessary; This creates a draft which will soon reduce the _ temperature. However, if the heating is closely watched such a con- i, dition should not arise. In order to maintain the proper temperature in the potato house one cannot depend on mere guesswork. It is, therefore, necessary to have " three or four reliable thermometers distributed in various parts of the house, as otherwise it is impossible to know that the desired temperature is being maintained. In addition to thermometers, one or two hy- grometers, which indicate the relative humidity of the air, are very useful in the proper operation of a sweet potato storage house. The form of hygrometer shown in figure 41 indicates the amount of moist- STORAGE AND DISEASES or IHE SWEET POTATO IN TEXAS. 13 ure in the air. For example, a reading of 60 indicates that the air around the hygrometer is 60 per cent. saturated. The danger point in the potato house is about "/0. If the reading is near or above 70 it indicates that the air is too moist. The reading should be main- tained below 70, and should generally run between 4L0 and 70. Both thermome-ters and hygrometers should be hung up at a height of about five feet. In addition to the indoor thermometers and hygrometers it is desirable to have a thermometer and hygrometer outdoors to indicate the tempe-rature and moisture in order to take advantage of all favor- able outdoor conditions. STORAG-E PERIOD AFTER CURING. It has already been stated that as soon as the potatoes have been cured the temperature should be reduced to 55 degrees Fahrenheit and kept as nearly at that point as possible. This is accomplished by the proper handling of the ventilators and Windows. It is usually quite easy to keep this type of house cool and dry. During a clear and dry day with the outside temperature registering from 55 t0 60 degrees, all ventilators should be opened so that plenty of fresh air can circulate through the house. Whenever the weather is rainy or the air is damp, it is necessary to- keep the house well closed so as not to let in any outside air. The fiue ventilators should always be kept open except during cold or wet weather, as thereby a constant circulation of air will be main "tained in the house. It is important to have the flue ventilators and the ventilator under the stove open, whenever a fire is required in the stove, except during very cold weather, when all ventilators should be kept closed. In case weather conditions are such in the fall that it is hard to keep the temperature down to 55 degrees, the house can be opened during part of the night, especially on dry and clear nights, but, of course, this should not be done during damp weather. The manager of the house should have no trouble in keeping the house dry and cool if he uses good judgment in handling the ventilators. The reading of the hygrometer in the house and outdoors is a good guide as to whether or not to open the ventilators. The house should be kept closed whenever the hygrometer indicates a greater humidity on the outside than on the insider The temperature of the house should never be allowed to go below 45 degrees, and it is always safest to start a small fire whenever the temperature goes down to 49 or 50 degrees. During cold weather, if the house seems rather moist as indicated by the reading of the hygrometer, one can easily drive off this moisture by starting a fire in the stove, being careful, however, not to let the tem- perature rise above 6O degrees. DISEASES OF SWEET POTATOES IN STORAGE. At the beginning of this bulletin it was stated that the storage prob- lem is mainly one of diseases. The manager of the potato house should never. lose sight of this fact. The underlying causes of the greatest 14 TEXAS AGRICULTURAL EXPERIMENT STATION. losses from rots are usually found in improperly constructed houses and f poor management. There are a large number of diseases capable of 1,! rotting the sweet potato. In fact, the latter may become a real garden *¥ for the growth of various fungi. However, we shall confine our dis- cussion only to the two most important diseases which the storage man { has to contend with, namely, soft rot and black rot. Those who wish)‘ i to get more extended information on diseases should refer to bulletin é No. 249 of the Texas Agricultural Experiment Station, dealing with field diseases. SOFT BOT. It is no exaggeration to state that in some sweet potato houses which ‘"- lose heavily from rots, most of the loss may be attributed to soft rot._. This disease is well known to the farmers who store sweet potatoes. It I’, is generally known as mush rot, vinegar rot, or leak. As its- name indicates, it cannot be mistaken for any other disease. Botted potatoes become so-ft and mushy (Fig. 39) and at the least touch of the fingergii or from pressure break open, and a. clear, brownish liquid comes out. i‘. A few days afterward there will be noticed in the house nume-rous small j gnats. They are merely little flies which lay their eggs in therotted 3 potatoes. Some people believe that these gnats are the cause of the i; rot, but they are only an indication of the presence of soft rot in the _ house. Frequently also the potatoes in the bin appear Wet as though water had been poured on them. This, too, is an indication that in that vicinity there are one or more soft rotted potatoes which have * broken open and spilled their juice on the healthy potatoes underneath; , and also become covered with a whiskered growth of‘ the causal fungus .1 (Fig. 39). If a soft rotted potato remains in the bin untouched until g; the end of the storage season, it will usually lose all its moisture and become very hard, in which case the term dry rot is often applied to it. In fact, many growers mistakenly believe that this dry rot has no con~ nection with the soft rot, but as already stated, this is the final stage‘ i_ of the disease. Usually a house full of potatoes that smells of vinegar " indicates the presence of considerable soft rot. This condition may be met with in houses which lack the necessary means of ventilation, in which case it is not uncommon to find the moisture actually dripping from the inside walls of the house. Such houses can, of course, be 5g corrected by the installation of more doors, windows, and ventilators. a; The cause of soft rot is "a fungus. It is the ordinary bread mold g fungus which is often found growing on bread when kept in a tightly !- closed vessel. This same fungus also causes a soft rot of the Irish? potato. The spores, which are very small and from which the fungusj, grows, may be found floating in the air and clinging to the dust that-T ’ is brought in with the potatoes from the field. As long as the potato house is kept perfectly dry and properly ventilated these spores will not germinate, just as seeds of higher plants will lie dormant in a dry so-il. . As soon as the air in the house becomes heavily laden with moisture and this air is permitted to remain in the house for any length of time, ' the spores will germinate, penetrate the sweet potato and produce the ;:, _ mush rot. ’Bruised potatoes will naturally rot quicker than the sound , ones, as the bruises or cuts merely present an ideal opening for these STORAGE AND DISEASES or THE Sulnm Pomro 1N TEXAS. 15 germniated spores to penetrate. As a matter of fact mush rot or soft rot is seldom found in properly ventilated houses and Where care and attention is given to the house. On the other hand, where a high per- centage of soft rot is met with, it may be taken for granted that either badly bruised or frozen potatoes have been put in the house, or that the house was overheated or not ventilated sufliciently. While soft rot is an important disease in the potato house, it can be readily controlled. by bringing in well handled potatoes and by giving due attention to the heating and ventilation. The spores of soft rot are found everywhere in the air and the dust and do not necessarily have to be brought in from the field, although they are met with there. BLACK R01‘. Black rot is next i.n importance to soft rot. This disease is pri- marily a field trouble and when found in storage is always traceable to disease-infected soil in the field. It is possible under careful manage- ment to keep down the spread of this ‘trouble to a minimum. Over- heating in storage will nearly always encourage the spread of the dis- ease, if infected potatoes have been brought in from the field. Usually black rot will not spread in the house as long as the skin of the potato covering the black rot spot is unbroken. However, as soon as the skin ruptures there immediately develops the fruiting stage of the fungus. Under sufficient heat and moisture these spores will ooze out in little yellowish droplets on the surface of the potato. The numerous mites usually present in the house are very fond of and will come to feed on this yellowish liquid, which contains the spores or seed of the fungus. In feeding, their bodies become smeared with the black rot spores which they carry about and spread from potato to potato. It is possible so to manage the house as not only to minimize the spreading of the spots on the potatoes already affected but also to prevent the cracking of the skin and development of this fruiting stage. Black rot itself is only a skin-deep disease. (Fig. 40). However, its presence is very detrimental to the potato as it leaves a decidedly bitter quinine-like taste, and makes the potatoes when cooked unfit for eating purposes. Besides, black ro-t often opens the way to soft rot, as it deadens the disease-resisting power of the potato. Black rot in the house may be controlled by giving due attention to the temperature; by seeing that during the curing period the temper- ature never rises above 80 degrees; and after curing by maintaining a temperature of about 55 degrees Fahrenheit. Moreover, if the crop is grown on uninfected soil, and carefully se- lected and treated seed are used, there should be little damage from black rot. There are, of course, numerous other diseases which may attack the sweet potato in storage, but usually these are secondary and follow in the wake of either black rot or soft rot, and because they are not suf- ficiently important they are here omitted. The managers of potato houses should be cautioned never to go through the bin with the view of sorting out bad potatoes. They will scatter spores of disease producing fungi and hence will do more harm 16 e TEXAS AGRICULTURAL EXPERIMENT STATION. than good. It is much better not to handle them until they are ready for shippig. THE BUSINESS SIDE OF POTATO HOUSES. The first year of the operation of a house is the most critical year. There are several reasons for this: 1. The community is liable not to produce enough potatoes to fill the house and this is especially true if the house is of large capacity. It is, therefore, Well to begin with a small house and add other units from year to year as potato growing increases in popularity with the farmers. Farmers must become accustomed to handling potatoes Without bruising, as bruises Weaken the power of the potato to resist the disease producing germs. 3. The manager not being able to fill his house with carefully han- dled potatoes, will be tempted to accept inferior potatoes and thus add to the difficulties of keeping down rots. 4. The manager himself will present a problem. The business of storage will be new to him. ‘If the owner of the house is in imme- diate charge, or if a. thoroughly capable man is hired, the business will be quickly mastered, but if an indifferent man is hired, the losses may be large. Enough wages should be paid to hire a good man and to cause him to» take a real interest in the problems of storage. As the storage period runs only about six months, the manager may be profitably employed in growing slips for sale. This is desirable for three reasons. First, it will add to the income of the house and help to pay the manager. Secondly, if the slips ‘are properly grown, it will ' supply the farmers with plants free of disease and will thus cut down losses during the next storage season. Thirdly, it shguld also stand‘- ardize the potatoes grown in the community and sold through the house. MARKETING. With farms located near large cities, the marketing problem is sim- ple, and a small house on. each. farm is very satisfactory. When the distance from market is such that shipping by rail is necessary, suf- ficient potatoes must be produced and stored to fill at least one car. . This can be done by a single farmer with a house on his farm or by a group of farmers co-operating in the building and in the operating of a large house located at a railway station. There are advantages in both methods. Before being shipped the potatoes should be carefully regraded into the standard grades and all those that do not come up to the required specifications should be discarded. There is nothing more important in successful marketing than to ship carefully packed and graded prod- ucts-such as the market wants, thereby getting the top prices and estab- lishing a reputation which will bring repeat orders. Consumers are willing to pay a good deal more for nice looking products than for inferior stuff, which is high at any‘ price. Poorly graded products are not wanted by the buyers and it is poor policy to ship them. It is much STORAGE AND DISEASES or THE SWEET POTATO IN TEXAS. 1'7 more profitable to feed this inferior stuff to the hogs than to- try to sell it. Bushel baskets, hampers or crates are good containers to use p tor shipping sweet potatoes. They‘ should never be shipped in sacks (Fig. 1'7) for fear of bruising and consequent rotting. CARE IN SHIPPING. Sometimes after potatoes have been perfectly cured they spoil while in the car or after they have reached the jobber on account of improper handling. One case is recorded of potatoes loaded into a car that had ice ln the bunkers. The potatoes, of course, spoiled badly in transit, and after being taken from the car; and what would have been a pro-fit- able season for the house was turned into a loss, simply because the sweet potatoes were chilled by being in an iced car. Cars should not be loaded during cold or wet weather if possible, and for long shipments during cold weather it is sometimes necessary to provide artificial heat in the car to prevent chilling. Oars should be kept dry and cool on the inside while they are conveying potatoes to market. When shipping one should give billing instructions to keep the vents in the car open during cool and dry weather and closed dur- ing cold or damp weather. The jobber who receives potatoes should store them in a room that may be kept as dry and as near a temperature of 55 degrees as possible. The retailer and consumer should store them with like care for best results. It should always be remembered that even cured potatoes are- liable to rot when improperly handled after being taken out of the house. » TEXAS STANDARD GRADES FOR SWEET POTATOES. The following grades for Texas were established by the Commissioner of Agriculture according to Chapter 181, Acts of the Regular Session of the Thirty-fifth Legislature: Grade No. 1. This grade shall consist of sound sweet potatoes of similar varietal characteristics which are practically free from dirt or other foreign matter, frost injury, bruises, cuts, cracks and damage caused by disease or mechanical means. The diameter shall be not less than one and three-quarters (1%) inches nor more than three and one-half (313) inches. Five (5) per cent. by weight by any lot may be below the least or above the greatest diameter prescribed, and in addition, five (5) per cent. by weight of such lot may be below the remaining requirements of the grade. No. 2. This grade shall consist of sound sweet potatoes of similar varietal characteristics not meeting the requirements of grade No. 1, which are free from serious damage caused by dirt or other foreign matter, frost injury, heat, decay, bruises, cuts, sears, cracks, dry rot or other disease (including weevils), or mechanical means. The diameter shall be not less than one and one-half (1%) inches. Five (5) per cent. by weight of any lot may be less than the diameter prescribed. and in addition, five 5) per cent. by weight of such lot may be below the remaining requirements of the grade. 18 , TEXAS AGRICULTURAL EXPERIMENT STATION. DEFINITIONS AND EXPLANATIONS OF GRADE’ REQUIRE; ‘f; MENTS. a. “Sweet potatoes” include yams. b. “Diameter” means the greatest dimension at right angles to any 3 portion of a central line running through the sweet potato from stem cnd to root’ end. ' ; c. “Practically free” means that the appearance shall not be injured z. IO an extent readily apparent upon casual examination of the lot, and that any damage from the causes mentioned can be removed by thei ordinary process of paring without appreciable increase in waste over T that which would occur if the sweet potatoes were perfect. d. “Free from serious damage” means that the appearance shall not be injured to the extent of more than 20 per cent. of the surface, and that any damage from the causes mentioned can be removed by the i. ordinary process of paring without increase in waste of more than 10 » per cent. by weight over that which would occur if the sweet potatoes were perfect. Fig. 1.——Photo showing exterior of the Texas A. and M. 5,000 bushel sweet potato house. Fig. 2. Interior view of upper and lower bins. Fig. 3.——Loading platform. Fig. 4.—-Poor method of stacking hampers. Fig. 5.——Middle aisle trap door ventilators. Fig. 6.———Sweet potato crates. Fig. 7.——Hampers used for storing sweet potatoes. 2O AGRICULTURAL EXPERIMENT STATION. o 12p Fig. 8.—-Front gate, showing how potatoes are to be taken out of bin. Fig. 9.—Side afs‘e, trap door ventilation. Figs. 1O and 11.—Correct Way of stacking hampers during storage. Fig. 12.—Showing stove and flue. 21 STORAGE AND DISEASES OF THE SWEET PUEATO IN TEXAS. . a .>&H11UNHW..|:;\. x§a .1. I111! II l a}, .1@! . ; 1 I l» '1 l \ |l v I, at all- I"~,I Lvllr-Plkutrfurl ,5 . . ‘Pi; . §Vw§wL WEN“ NP: \w§\i\§\.. first vn 3:3. \u \\\\\\ \ . \v\.0 ~\\ .30‘ st\\\3\\.. i \\\§\ \\\\n\\\ o§.\~v h ox. »¥\k \.\§\L\>..\ \ I\\\\ QV\\K \\\\ .\\\Kb. r . \\ m\\\-\\\.\ N\§\\\. \.\l\\\ ~§~ .‘\\}\ \\\n uh. § \\ \\c Yuq». R .. . If \\ y \\ . u»; V. W.» O 9D h mafifiw. N?» i. Em. 5.lm€8 W355 38.. »\\\\\\ V? XQQ‘! “flit. 22 TEXAS AGRICULTURAL EXPERIMENT STATION. dune: .0825 oood .2 una .4 naxuH “o moflwk/ofio %1m=ma2. mcflwagflllgvfi 9h £11.! o .1 \\\\ Hbs‘ \\\\<\v\ a\ \\...J\\ \\\_\\ l‘ \\\\ \\\\\\n ‘KSQKQ . .\\\A\\\\\\h\ \\\\\F\..u|\|\\\\\ h.v0b\ u‘ \.!\\1\. \\\\\ U.u\\n\5\\ .~~\\Q\ N. . :!\\ ‘\\\\‘ »“\.i\.\ \@\\\\~\\>x \>\\\ >u.\\\.\ 3\2v\§v\ V\S’\\\.\\ £5 h‘ \\\\z\I1 vv\\\ K \h.\...u\\\.\._\ ‘\.\\\M\\\§£‘}J.%.\M\ m‘ \\IRo \\\\\\ \\ 1x h$\\\\\\ u\\\\ .. \5.~..\\.\\§\ .. “\ .\\\\\n\\\ \»\\\\\ v3“ \\\\€\x< !\\..) 23' STORAGE AND DISEASES OF THE SWEET POTATO IN TEXAS. I\ \\.£\\..\\ \r A. \ lrxn \\\\\ \i\ i¢.\\|. ‘x .P\\ 1 w . \\3~. \~\\ .\%\\\\ u . aéi- Z >\..\b / kwfln. “Usx . . . v 131., Nu! ‘x n§h> §S \V§\\$: w!‘ n» ¢..\\\\n T . _ ‘l, §%R»\\.§\\.~ 4 . \§\\\\ 8S.“ .. ., %. M I \\\ \§\$\s \\\ \\.§\ .N~§\\\\ n?‘ 4 p 1 \\u\ \$ \\\A $11} Q.>\\\\ h3\\§\ hvhnx % a t\\\\n\u. fin \n\fi\\...\..u§ h. m.» \\\¥ . 53...}: 1 . n \1\§\ 3gb \v xix! H \\\§\\\v\\\\\i\ul .. J \¥\w\\!.h l \!\ !¢\\\\ \o\ \ \ a 2 5 \s\~\, wmwanuawuuk f, . a , Ni.=\a 133$.‘ m.§\\\\\\\ \$.\\to\ u] 2k xix 1Q} z NVK 0\\\\\V \\\\\\\ .\\\\\\\.. \§ n» v3! * \L<\\\\\\ \\\\\ .. W \\,N\\\ \\\ u\ w»? \V\\fi \\\§\\\NVv 11 :1\\\ 4W $\\~\\\ g f I.!\~T 1 .. L.\~\\\\\ \\ \1fi - \vN\Q\|\l§\~$\. L.\\\\\\ 32x \\ Li=h\\ h‘ \~ Sb..\¢»\\ .\\\\.- . _. .. ‘ \\\.\ |\\fl\\\n§\ . I» .\ .2. \\“\\L\\\\ .. . \D~N Q\2-.¢/¢ A; /'I a f’ Fig. 18.—Upper part, drawing showing pier detail; lower part, showing post detail. M. 0 I T A T S T N m I I R E P X E L m T L U C I R G A m E T 26 AGE noflmwusowmmcm3osm mfifififilumfi firm kQuM-k’ "a V: °x ‘Nqm. HEWE E E E L 1 4E E; E ET E THEM E T Lg T T‘ i1 E E T nu E HT I E T . T. E IMM E STORAGE AND DISEASES OF THE SWEET POTATO IN TEXAS. 2'7 P57fifL fH/M/VE-l" Vi/Vr/z. A T/o/v Jae/e f1 /-'0" _. ~. ‘la-a ~79: 0 vuvnil- (“v-Wax f A \ \ Ki Z 1 4 w Q V; / Jacxa/zrflu?‘ + w i } / 1s, éz/flJa/df fi \ w} t, / hwr”... l § ' / rdénmnnf ~: 1"“ ~ X <’P‘W ~44 t _ '_ A4” "1444 I Pvmryc/ frr/re/ o:/ass @ x440‘; -' kfld l- \ ‘\ @ / off aufsn/c 44/1 41/ 400/ d/zws j p”, T_ z -* _/, / / _ Zea/Ir A/r nffi?) Iran/fits‘ mv/zv/rce I _' lpéy/w I "" / _ afca/z/p/r // f/rejae: ouf x/firn p//r/u/a»>‘ -r_ x -fi-- L5§{'r-m7£( ‘w? I} ».< -4,.~/ 4.! a?‘ ~44?‘ % f/aaz Zen/n F é \ fla/e //r J/ara ass/fig _ _ _ " 25o" n,» KmJ/n A/n‘ 6 "ta/zcra/c Jana: . /;- A? M“ zedrnfvr¢/hj Fig. 20.—Drawing showing detail chimnéy ventilation. wfiEmb En Ho 52a 3oz m5??? wEBwHDIIAN. wE .O>::\.\.\ § §uAQ4 \\\\\.3\\\ \K\\\\\.w- nm- JH . . . .\ . \\\\\\.-|\u\ \\U\\\\\ $0 i . i iU\\\\ .\.\\\D|V l...u|hQ§\ i i i W Bii? \\ h‘ .mk~\x\\qxa . i? . .i . . . i i . ~¢ii;».i~ f.» _ . . _ i i i, i i .| i. W . I . . ax‘ |1\|‘ NW"|.|_ a ,l\li\h .§\\\\..\\ 12x». .. i _ i . . \Y\\.\\ \\\\.\\~\\o ii i . =$§u3i\ Qws. 53K _ . i i i N i i P _ K a... \. i _ i. i 28 29 STORAGE AND DISEASES OF THE SWEET POTATO 1N TEXAS. §x§x~t \Qn Q\\. fl.\$\n |\W\\\\§\\\\ .\\\<\\\\ .\\\ \ §§ ..<\ \.‘\ .. \ _~1\\\\ (\ ...f ‘ .. r (y. . ./ \H\M Q\ 5 F ._>'2.¢/¢ J L’ /-' a " A???) I/v/vik F190”? 2002s. J6" - _VEV/// fkera JV/fl/Ik/ JlW/rrs E ' ‘Pour; /r f/7‘ aa/u/zfiba; arr/a)‘ />:/’ d/fiz/ l/vwfla/fl/eéas Kit/e t ‘D0 OR ' ca/a/ w/ w/ Arf/ef X/rfl‘. //l/¢ .¢//»v.m¢=. Mir/r pwf n; /u/»Jer fir ,//¢/ 4/ {x-yé 4/,// 4 arw/rr/ w»! Jaw/c - 44w¢ .. Fig. 31.-—Drawing showing detail of window shutters and of outer door. 36 TEXAS AGRICULTURAL EXPERIMENT STATION. b" i [pa/l fles¢ ' I‘! Ifr/ldl/J fi l’ roof fir»: ~—1 ' ' i‘ \ ‘p: T“. gi k» g i A I/oel I I Q I HQ . 21a" 4/4‘ Hf’ /’.9’ //0" Z "X LFI/aoy aax/a/ 72 a/wypf _ | fa/ axfrz Jlffl/dd/I." I | fir,» 2'24 "Kb/inure. J/nrla £170 A ELE VAT/Oh’. 150v PEA MIA/G. Fig. 32.—Drawing showing end elevation, bin framing. 37 STORAGE AND DISEASES 0F TH}! SWEET POTATO IN TEXAS. . »Ll,. vwfflurwif bv fr»! !E\. \f\v}..l\.lfl.kf¢l| . l1. 1 1 ‘ = 1J3)“ . » ‘ 1 RF». v .\hk \\» KuWE \11vl\ \‘J\|> ulh N t»..\\ |_| .. Jli 1.14%‘ M .1 V I _ I H_ H EA msvlh “wk H .._\:Iv<\ \ .1\‘§\‘ < Jw A W I x» A _ w _ P T a“ 4 J € 5 t ; W”, F M 4,. . 1 .\>i%\i\w\\>1l flvvv$flm a .m<§§+hW %\§Wml . . v .._ ,. \\\ o\\ \3..N\\ \\\\\<.. \\ \\§\ 4. A p it \§\ \§\\nn m‘. Nmsxk \\n\¥\\,\w§ \.W§\n\ J “fin .~ h. .< f... .¢. 0 0 ¢ w 0 w “if; i. >w fi , - ¢ » 0 ..‘_ A _ kw _ _ x _ .. w _ & . \ ,._.> l \\.v\ ||| 1 .. "w m\\k\ \\\n. w QQSM‘) mum. rwvv} QW QWQN; mm. QY-ihW . . III v. _ 1 \_\§\\.»...| .. \\\\\\\\\!.. \\\\ §u.\\\ r kx §\ .3. \\\\.\ \» . .§%b\\\v\n §\\ \n¢fi\\ N \\ \\ \. \\.\-\>Rh l t . . ,.. p 1 _>>._ E12; HL WU m....1_Lw>"_ H?HIP>J+_ _ wvhi§< BM. »\W\\.Y.\h\+ \.\\Q\“ \»k \ms.1w\&~,w m... xnh SW. mi. wnwluisim mrosmum Em: o» <@:»:»So: =2... moowm mum ma? _ l ) i n. 38 TEXAS AGRICULTURAL EXPERIMENT STATION. .056: ofiwdoa 3o?» E win visa; ha. v03»: .3 cofifiaubo mEBoam n33? ofiwimumwmn~|ém 4.3m uwao: OPQv0 QTIZ _._./// 5 5 ménw \\ \ / § \ \ \ // 116s f F62 STORAGE AND DISEASES OF THE SWEET POTATO IN TEXAS. 39 _\_ ,//; I g/v/s / "spam: infirm»; F/o a r JE/Jfif- _ ..i2v-:1o£ V£JYZYLJJ 75p ’ PLflrFaz/v Zita’ Irv/J JVn/rpa/i-fieamaf; or f/afea- V/lenfi/n cmvf/ucf/a/y /.~>" an‘ m: ed Fig. 35.—Drawing showing inside platform for storage of hampers. [\\\ I Q15. Il/K ’:-l"“}~" II tit/u’ e f" Hi3)!!- Qiiécnflfam t ¢_5‘¢¢9/¢ / S /—-'0 " Fig. 36.——Drawing showing section of trap door ventilator. 4O TEXAS AGRICULTURAL EXPERIMENT STATmN. F}. 00.2 lfvv/I’ ,pfm/4 Jan/a /;/-'fl H 23c 192v. Ja/s/sbrzfi- . ‘r0 l, A/OTE—~ ' "' ' u 6/90/15 an f/oor deaf/was‘ mayféc \ $ '0 \D >( \ l I7 |II ; ‘sef fa p/e/¢nf A \\N f/ao/ aecf/o/ms Q? fafl/n; ffi/u. \ h Th0 aéknens/an ma/ Vary w/f/z - ¢an0’/f/oms an/‘ab, AYZTFGPZ‘ . -+_ (—¢__ fix "F .D£~ 7/11 11. F1. o 0g ‘Jacvvo/va Fig. 38.——Detail floor sections. 41 STORAGE ‘mm DISEASES 0F ‘PHE SWEET POTATO IN TEXAS. ma. wmvlmc: no" o» méow» vim-flown. 1mm. fiylwsafl 3».