Historic, archived document Do not assume content reflects current scientific knowledge, policies, or practices. UNITED STATES DEPARTMENT OF AGRICULTURE Contribution from the Bureau of Plant Indusiry WM. A. TAYLOR, Chief Washington, D. C. PROFESSIONAL PAPER March 16, 1916 MOISTURE CONTENT AND SHRINKAGE OF FORAGE AND THE RELATION OF THESE FACTORS TO THE ACCURACY OF EXPERIMENTAL DATA. By H. N. Vinauu, Agronomist, and Rotanp McKEs, Assistant Agrostologist, Office of Forage-Crop Investigations.+ CONTENTS. : Page. Page Introduction esses eee ene ene a ae ek es 1 | Variation in the moisture content of growing General plan of the experiments.........-.-- 2 alfalfa during a single day...-............-- 31 Use of samples in correcting forage yields... 3 | Moisture content of baled hay............... 31 Relation of the stage of growth of forage plants Shrinkage of hay after storing and variation in to their moisture content.................: 22 weight due to changes in atmospheric hu- Loss of moisture in forage during the early PROW EG BA Eig Se A sR a a ce a are ee 32 Stazesiohcuringssie ste. sano e ene =] Seles 273 | SSuMM aye Ea ae Nee ed ae ee eee 36 INTRODUCTION. Agronomic literature contains but little in the way of well-planned investigations on the subject of the moisture content of different forage plants either green or cured, a matter which is mtimately related in farm practice to the proper handling and wise marketing of forage crops and in investigational work to the correct interpreta- tion of yield data. This subject is of sufficient importance to justify much more attention than has previously been given to it by experi- menters. Careful investigators have long recognized that many of the published data on forage crops are inaccurate, on account of the uncertain amount of water included in the yields. The term ‘‘air dry,”’ as used in the investigations described in the following pages, refers to that stage of curing when the humidity of the forage and the humidity of the atmosphere have reached a state of equilibrium. The percentage of moisture in the forage when air dry of course varies with the changes in atmospheric humidity, 1 Messrs. W. J. Morse, H. L. Westover, M. W. Evans, A. B. Cron, and R. E. Getty, members of the staff of the Office of Forage-Crop Investigations, have contributed quite largely to this publication by their assistance in collecting and preparing records of the numerous samples required. 21216°—Bull. 353—16——1 2 BULLETIN 353, U. S. DEPARTMENT OF AGRICULTURE. but this variation is within rather narrow limits. The term ‘field cured”’ is more indefinite, denoting that condition of forage which obtains in general farm practice when the hay or fodder is consid- ered sufficiently well cured or dried so that it will not spoil when placed in bales, stacks, or in a haymow. In this stage the forage is very seldom completely air dry. Most publications on forage crops use the term “‘field cured”’ to denote the condition of the forage under consideration, but such a term does not imply a uniform percentage of moisture, and little or no care has ever been used to indicate even approximately the moisture content of the forage when the yields were determined. It is, therefore, impossible to mterpret correctly many data found in such publications. The variation in the moisture content of forage when yields are taken is often greater than the actual difference in yield that we may expect from improved varieties or improved ‘methods. There is little dependence therefore to be placed in experimental results along these lines until this factor of error is eliminated, or at least greatly reduced. The data presented in this bulletin are sufficient to sug- gest a remedy for this difficulty, and it is hoped that experimenters will consider carefully the method here indicated. Aside from the experimental value of this work, it has an economic significance, in that it points out the relative weight value of forages at different stages of maturity. However, the economic side of the question is not discussed in detail and is given only as it forms a part of the experimental data presented. GENERAL PLAN OF THE EXPERIMENTS. During 1914 a series of experiments was carried out to secure data on which to base a sampling system that would give greater accuracy to field tests in forage experiments. In connection with the efficiency of the sample method, investigations were also carried on to determine the amount of moisture in forage plants at different stages of devel- opment, the variation in moisture content due to locality and to cutting at different times of the day, and the differences in loss of weight when samples are dried in the sun as compared with those dried in the shade. Information was also secured on the rate of moisture loss in forage in the early stages of curing and the changes in moisture content of hay stored in bales and loose in a barn. In conducting the experiments at the various places the methods followed were the same or varied only in minor details. Half-bushel and bushel cotton bags were used to receive all samples except the largest, for which common burlap grain bags having a capacity of 2 bushels were used. For inclosing the bales of hay a close-weave burlap was used. In taking samples of field-cured forage, care was MOISTURE CONTENT AND SHRINKAGE OF FORAGE. 3 used to have each sample representative of the entire crop. Material from the outside as well as from the middle and bottom of the wind- rows or shocks was included. Samples of green material were taken by cutting the plants either by hand or with machinery, each sample including only that part of the plant that is used in making hay or fodder. The samples of different sizes in both the field-cured and green material were replicated five or six times, and each sample was marked with a tag bearing a number and other data necessary for identification. In taking samples, the work was done as quickly as possible, to avoid loss in weight by evaporation. Each sample as soon as prepared was weighed immediately. After the samples ' were placed in the containers and weighed, they were stored in a favorable place to facilitate further drying and at the same time were given protection from rain. In ascertaining the total water and dry-matter content of the various samples, determinations were made by the usual method of oven drying. For this purpose a special oven having a capacity of 164 cubic feet was built. Steam heat under pressure was used and a temperature of 100° C., or a little above, was maintained. In the following account, the outline for each experiment is given as it was carried out at the various stations, and this outline is followed by a tabulated statement of the original data from which the sum- maries are prepared and conclusions drawn. USE OF SAMPLES IN CORRECTING FORAGE YIELDS. McKee, in the Journal of the American Society of Agronomy,? gives a general discussion of moisture as a factor of error in determin- ing forage yields, wherein it is suggested that forage-yield data can be made much more nearly comparable if small samples taken at the time of weighing field-cured or green material are used in determining the moisture content of the material and these data used in reducing the yield either to an air-dry or to a dry-matter basis. In the experiments described in the present bulletin, the efficiency of correcting ordinary green and field-cured forage weights with 2, 4, 6, 8, 12, or 16 pound samples was determined with the following crops: At Arlington Farm, Va., alfalfa and a mixture of tall oat-grass and orchard grass; at Chico, Cal., alfalfa; at New London, Ohio, timothy; at Amarillo, Tex., sorghum; and at Hays, Kans., sorghum. To provide a basis for checking up the moisture loss in small samples, 100 pounds of ordinary field-cured forage were taken from the shock 1 The samples of tall oat-grass and orchard grass at Arlington Farm, Va., were prepared by H. N. Vinall and H. L. Westover; the alfalfa at Arlington Farm, Va., by W.J. Morse; the alfalfa at Chico, Cal., by Roland McKee; the timothy at New London, Ohio, by M. W. Evans; the sorghums at Amarillo, Tex., by A. B. Cron,and at Hays, Kans.,by R. E. Getty. 2 McKee, Roland. Moisture asa factor of errorin determining forage yields. In Jour. Amer.Soc.Agron., v. 6, no. 3, p. 113-117, 1914. 4 BULLETIN 353, U. S. DEPARTMENT OF AGRICULTURE. or windrow and 500 pounds of green forage were taken immediately after cutting and placed on a canvas to prevent loss of weight other than moisture. When the forage on the canvas had become suffi- ciently dry, these bulk lots were placed in burlap bags and kept in an open shelter until they ceased to lose weight. Composite samples, 2, 4, 6, and 8 pounds in size, of field-cured forage, part from the outside and part from the inside of shocks, were secured at the same time and from the same material as the 100- pound lot before mentioned. These samples were weighed at once and put aside to become perfectly air dry. Samples, 4, 8, 12, and 16 pounds in size, of green forage were taken immediately after cutting and were treated similarly. Samples were replicated five or six times to check the variation due tosampling. Allsamples were taken at the stage of maturity generally recognized as the proper cutting time for each crop. The samples were kept in a shelter and weighed at intervals until they ceased to lose weight. They were then shipped to Washington, D. C., for the purpose of reducing them to a moisture- free state in the drying oven. The intention was to secure samples of timothy at both New London, Ohio, and Arlington Farm, Va., so that each crop would be handled at two stations, but an unfavorable season caused a failure of the timothy crop at Arlington Farm, and it was found necessary to substitute there the mixture of tall oat-grass and orchard grass. In Table I an attempt has been made to arrange the data so as to make the conclusions to be derived from them as clear as possible. Column 1 contains the number under which the identity of the sample was preserved from the time it was prepared until it was finally weighed from the drying oven. Column 2 gives the original weight of the sample, whether green or field cured. Column 3 gives the weight of the sample at a date between the time it was prepared and the date when it was considered air dry. This column is intended to show about what time is required for each sample to lose most of its moisture, that is, when it was drier than field cured, but in most cases not yet air dry. This column is blank in sections A and B because no weights were obtained between the date of cutting and the date when thesamples were completely air dry. Column 4 carries the air-dry weight of the sample. In some cases this was the weight obtained just before the sample was placed in the drying oven, but where an earlier weighing made at the field station showed the sample to be practically as dry at that time, the earlier weight is given. Column 5 gives the weight of the samples oven dry and represents the dry matter contained in each sample as nearly as it can be deter- mined in an ordinary oven. MOISTURE CONTENT AND SHRINKAGE OF FORAGE. 5 Column 6 carries a statement of the percentage of moisture in each of the original samples, as determined by the difference between the original and the oven-dry weights. It is recognized that this loss may not necessarily be exclusively water. Slight losses may have taken place through volatilization of substances other than water or through fermentation due to enzyms or bacteria, but such losses are undoubtedly small when the hay has been quickly cured. The percent- ages as given are determined by using the original weights of the samples as the base. It is recognized that this practice is open to criticism, owing to the fact that the original weights vary in relative importance, due to the differing percentages of moisture which the samples contain. This criticism is of little importance in the present case, however, since the percentage of moisture is very nearly the same in each group where a comparison is made. The use of the absolute dry matter as a base from which to figure the percentages was tried, but this method seemed impracticable, because it makes the percentages so at variance with the moisture percentages as usually given. Column 6 also gives the means of groups of three and sroups of five or six samples, with their probable errors. In tables where tliere are only five samples in each class the second group of three represented by the second mean includes the remaining two samples and the one next above, which has already been considered in the first group. For example, in section A the first ‘‘mean of 3” is based on samples 1, 2, and 3, and the second ‘‘mean of 3” on samples 3, 4, and 5. These means are set in black-faced type, so that they will be apparent at a glance. The consistency in the per- centages of moisture in each set of samples is remarkable. In only one case has the probable error for the group of six samples exceeded 1 per cent, and the probable error for a single sample averaged con- siderably less than 1 per cent, although in exceptional cases it ap- proached 2.5 per cent. The probable error was chosen as the most efficient measure of the comparative reliability of the different sizes of samples and methods of sampling. Since the moisture is here stated in percentages, means of practically the same size are dealt with, and the need for a term like the coefficient of variability is lacking. Column 7, as shown by the heading, is a record of the percentage of moisture in the air-dry material, the weight of which is shown in column 4. Column 8 gives the percentage of moisture which was lost in reduc- ing the material from its original state to an air-dry condition. The base on which this percentage was calculated is the weight of the original material given in column 2. The actual losses of weight in 100 pounds of field-cured and 500 pounds of green material under the same conditions as those surrounding the samples are given fol- lowing the tabulation of sample weights. BULLETIN 353, U. S. DEPARTMENT OF AGRICULTURE. TaBLE I.—Comparison of different-sized samples of forage. SECTION A.—GREEN ALFALFA COLLECTED AT ARLINGTON FARM. [Dates of weighing: Original material, Oct. 16; air-dry material, Feb. 2.] Weight. Moisture. Sample. l ; ; Orig- | Inter- eraiee Oven Original Air-dry Lost in air inal. | mediate. 7" ee adry. material. material. drying. Ounces.| Ounces. | Ounces. | Ounces. | Per cent Percent. | Percent. ANID sph Se ree en G45)- 2 3 eens 18.8 16.0 75.0 11.1 71.9 IN O32 eS er gg GA ee ee 18.0 16.5 74.2 8.3 71.9 Inf testy Sete eer GAsl oa eee 18.5 16.0} 75.0 1325 ri: MGA OLS... = 32 Ses aces eee, oe eee ee ee ee eee (eA eS US ho eee ee eee ores Sy EROS ees Bats GANS cet oee 20.0 18.0] 71.9 10.0 | 68.8 ING IEF G44 Koes 18.5 16.5 | 74.2 10.8 71.1 IE a7 lay BSS Sa Pe Ee ee ee | eee | So s0 2 SIO es ed ee Mean G5. 5. ee ee BESS ee eee saree. NEC 74.14 .344 | 10.740.510 71.0+0. 237 error Ofiis es ED e eel an rg a ee Je--220--- =) 2769 rate? Seis |: ot eee ING ARES chee eas 2 d2SkT SES Vee 38.0 34.0] 75.4 10.5 | 70.3 INO ode eee eee ee 1 oy Beas = 35.0 31.5 75.4 10.0 ey tod INONSE Lote POE aE aeS 125 ee 35.0 31.5 75. 4 | 30.0 Mood Meanie facccoe |i eel i wate TAP ort): lot tye ts 94.414 7007 1s) ce 4 4-0 ee ING IG SNE 232) Bee G28 1h See 36.5 32.5] 74.6 10.9 | 1.5 INGSIO. See ere ess B28 eee oe 36.0 | 32-0 | 75.0 eh rh 71.9 Meaniois sc. 5<2 | Eee eae. ete | eens eer 9.02: 127 so. eee Mean'et5 hci Ans —— ek é ES er tee 74.84 .225| 10.54 .129| 71.84 .259 Hrronge 2 | Re See eee <2 eG ee sae | 2 eee eet) ie been eee) (Ee es NO ise eee el 192 | PUL maui 51.5 46.0] 76.0 10.7 73.2 ING S4a2 ee ee Th! 9 ee ee ae ae Soa 46.5 75.8 11,2 72.7 INGA ee eee eee | 1O2 MESS Se Oe 54.0 | 48.0 75.0 Bz 71.9 Monnof3...<. eral cians. ae sees ae, P9564 (168 nee ee 1S Fee Eee a | op hacia te raed ee Cae ee 11.2 72.2 INOS 1582-4 See | AOD SS ier ae 52.5 | 47.0.) 575.5 10.5 72.7 | } Mean of3....----- ong Hepes ae BER Se (alee | 752-4 2081. ork beu se aloud Geueaeeee Mean of5...-.---- is. [ees eee Reena jo-c.2---=-] 95.54 -160 | 10302 407) Veaeseias Rrrorod sss se Se Sed ee ee cele eo eee eI of DAS Ne els ees 7 Ee ee a ee | INO. AG se tot ae DiGi sat eats 65.0 | 58.0 | 77.3 10.8 74.6 No sys o Seen Po Ul eee 67.5 | 59.5 | 76.8 11.9 73.6 Nieu6 Lia ere Sin Mientras } 68.5] 61.5] 76.0 10.2 fee Mean of3.000- 3s das Stipe Peete SEGA Bee terates ieee tias| 164°. 207)| a8? ok ee ING 19° 423.2 we gps 256 | Meee ete 67.5 | 61.0) 76.2 9. | 73.6 INO= 20 sh epee ee 256 So es ee 68.5 | 60.5 76.4 a Wave | Mean ars: 26235. 15 eee | [Sips Se SE eee Bt [eee oot (G2 (063 2:32.56 eee Mean of5.......-- jee ee eee eee eee | 76.54 .155 | 10.84 .251| 73.64 .155 rrp de ee aoa se ae oe eee eee ce ERE”) B BSR beade ae. epee es | | SECTION B.—FIELD-CURED! ALFALFA COLLECTED AT ARLINGTON FARM. [Dates of weighing: Original material, Oct. 20; air-dry material, Feb. 2.] i (74 hepa sie hae yt 32 | vies ee | 32.5 29.0} 9.3 9.6) [eae INGE Oo Re ot ae Nias cr) eee ig S050) 29.5] 7.7 9.6». > sfucaepeeeegaes INO 23 hee cee | 32 | sone Bross oes 29.0] 9.3 9.6 © ee MCA OF 32. 685 | ee eee Ue ee ned |e bc eo ee 8.8-£0. 294 |. 2-262 See Noe 2p}, bee | 32.0 29.0} 9.3 CE Maples Peeper oS Noi 25322 322 ores. BOS ae es bb 32.0 29.0) 9.3 9.3 242) tyifsskotee eee MeanNietS.. hehe ten Mugs Sse eee |e Eee eee eee! 9.8+0, 7 iki tee eee. bee Mea set ee | (Pi ee | es eee 9.0+ .193 9:50.045'|.- 2S Errorofi..-:.-:-- Besss5- - | Seo 32 PRE 2-2-2 SE pepe ee ee J pees 10wingtounfavorable weather conditions, this material was moved into a greenhouse shortly after it was cut, and the curing was finished there. are eeae be considered field cured, and the percentage of moisture lost in air drying is therefore dis- regarded. This explains the unusual dryness of these samples. They i MOISTURE CONTENT AND SHRINKAGE OF FORAGE. TaBLE I.—Coneparison of different-sized samples of forage—Continued. SECTION B.—FIELD-CURED ALFALFA COLLECTED AT ARLINGTON FARM—Continued. Weight. TInter- mediate. Air dry. Ounces. 64.0 Ounces. ee es Ss ee Moisture. Original Air-dry Lost in air material. material. drying. Per cent. Per cent. Per cent. 10.1 CO) Rare ee cote SER ey 10.1 HO Wie mee hein) Wars aeeeaee 10.8 10.2 [peessescossesc AOS es Or ee ees Ls eae 10.8 MQ RD aes rina | hee Ree 10.2 Codi «iat ee ae = DO LG 2B Os Rees soe Sara eee siete See 10.4+ .099 |} 10.04 .203 |.............. STA I Ue eS eer ee Ce Sas he ee 12.4 Ce a Liateaneh Rete | ts SO See Ts 4 VOI OF Sex SECS ees 13.0 50 ky (Rebs Megaman, Me abs 5° A BBR tS ease Sooooean al lSteeeCoanae aoe 11.4 SS Git cance ties ees aeny aa 1385 Qa Ris Won |i oe eee DOG SAO et aie el Se = [RIN a 12.84 .257 Oe PUG Tee ened Owl Nese ees eee Saeed See eS OSG it a oa Re ars al ies) 7 ETI Esato Pe Pa eee eg ae IPE AL 1 ET Ee ae ecient TUT Ue (Se 1 Pe CNR Ln a 12.3 DU Deg a iho ea Ree ate Reg reer 12.8 DC jemeryi taal a eee Acree ar a 11D epa Wel Maasai Ls Lt ee ee Pal had Sa 120-81. | IC Ose soup assaeee ee ee of a4 OG) lecinacioe oases sears ise SECTION C.—GREEN ALFALFA COLLECTED AT CHICO, CAL. (Dates of weighing: Original material, June 11; intermediate, June 30; air-dry material, July 23.] Sample. Orig- inal. Ounces. INONZ ORs se eas ecee 64 INOMO ete cciaces ee 64 NORD Sttsersscaice obi erscs 64 BN ONO Soace sec cecee 64 INOS ess Oeseneeoeoens 64 INOS Rye eee 96 INORS2P eee es see ace 96 INONSOMSo ro see aiccecee 96 INIO)s Si la ee a a ee 96 INONGDM Pees ee casee 96 Mean of 3.......-- MeaniOno tessa eeee DERE OW NS Soossoc INOHSOn Goose see Sor 128 INIOs O¥faseo qucLeeueEnae 128 INOMSSitseee ccicsicekiocae 128 Meamorsce. ccc a-- INOS OFS sie ee ciaeres 128 INO 4 Ole See een usa 128 Meantonsee sseoee Mieanvon 52 2.ascse IN ORDO sae cee 60.5 INGE Ie eee eee 60.5 INGE eee eee 60.5 INOe D0 4s se oee eck 60.5 INR Des eanene estes 60.5 INGOT 50G%a sence cae ce 60.5 IN ORS OVe race coat 123. 2 INGE AUS eek oe eee MABRY INO ED See eee 124.5 INOS SID Se RE eee 123.2 IN@ Din SESE Sas eee 124.5 N@ iD = as se aoe 124.5 17.50 17.25 17. 00 16. 75 16. 00 15. 75 16. 25 16. 25 16. 50 16. 00 16. 00 16. 00 33. 95 32. 70 31.95 30. 45 36. 25 32.75 34. 20 32. 45 35. 00 33. 25 33. 75 30. 25 75.2 76.0 75. 2 389 74.740. -370 . 574 2 71.5 7.5 72.3 7.8 74.0 7.5 73.2 9.3 73.5 6.2 73.2 "7.640.253 | 78.040. 249 ERS 72.5 11.4 75.3 8.4 73.7 10.7 73.7 9.6 73.3 7.4 75.7 “9.84 .407| 74.24 .258 8 BULLETIN 353, U. S. DEPARTMENT OF AGRICULTURE, TaBLE I.—Comparison of different-sized samples of forage—Continued. SECTION C.—GREEN ALFALFA COLLECTED AT CHICO, CAL.—Continued. | | | Weight. | | Sample. ~ : = rig- | Inter- = ven inal. | mediate. | Air dry. : of), lsh... re \Ounces.| Ounces. | Ounces. | Ounces. an 5 Se a | 187.2 50. 20 | 45.20 40.5 ik: Le as SE eS eeSine 50. 20 | 45.70 41.0 PMipee ne sees | 187.2 | 51.70 46.20 41.5 Meanlof 32-2. .-=. pseess=4 S222 s5222 [Ssss525-2 25255===- i RRR ema” | 387.2} 52.95; 48.20 43.0 | TY (Soe Sees Ae | 187.2 50.95 | 46.70 41.5 BAG ee oc Fae | 187.2] 50.20} 47.20 42.5 Mean of 3.......-- ee: Se Nibaca soo eects Seen Mean of6......-.- | AR ae 35) e S, e | Se Nee Sl |g ee rie Error oti --=- ree Pre ee tee ON | eee Rn | mae a GT i) Ne a es 251.2 72.70 61. 45 55.5 59 |e ee Os 251.2 73. 45 62. 95 56.5 24 RAEN ee 251.2 72. 20 59. 95 53.5 Mean of3 222 so5s3 |e ee |S ee ee eng | | Se ee ae, His eee: Aches: 951.2| 69.95| 60.70 54.5 bs eee 7G EON 76.95 62.20 56. 0 HL, So Ue ER ro 251.2 71.70 62.20 55. 5 | | Meanions 2524 ee | Geet Sey ee aie pie et] ) Ss Soe Meanot6:—s-— | foes sieboe arene | | Sil pty DEN iigeictt) Bt Sees Boo ee Se, eee fic 58 op Fo eee | See Bi ee Moisture. Original Air-dry material. material. Per cent. Per cent. 78.4 10.2 78.1 10.2 77.8 10.0 79503) 005s ee 77.0 10.7 77.8 11.0 77.3 9.8 46043 125 ||) ae | 77.¢+ -129| 10.8+ .113 4+ GIG). eee 77.9 | 9.6 7 RS 1 10.1 78. 7 10.5 93.03- 3005. - es eee 78.3 10.1 | 77.7 10.0 77.9 10.7 78:04..2098 | oy or ee 78.0+ .109 10.2+ .098 Ere 17 de eee ee SECTION D.—FIELD-CURED ALFALFA COLLECTED AT CHICO, CAL. [Dates of weighing: Original material, June 13; intermediate, June 30; air-dry material, July 23.J INO oars ee ace ING U5 26 taco ees INO2527 oot ee BNO 28 5 2 ee ee IN Ge 20 oe re ee ING 7500 USS. ee NGS og ene ee INOS 2 ee ee eee ING aa oe a TS US. See eee 2 eee ING Oo e Kets eee ING Sissi ae ee eS Mean of 3....-...- eked & 2 PeTOn Ob 23 al ee | ING haeee = eo oe IST s Ce es ae eee NG 539 hee ee eee Meanora oe eee: INO 30 see eee ee INO ore ee ING 2 eee oe Mean Ong lt = ee wet ee eee 28.5} 24.00 28.5| 25.25 28.5 | 24.75 28.5} 23.50 28.5} 24.00 27.2| 23.70 50.2] 51.20 50.2| 49.95 59.2| 48.45 50.2) 48.70 59.2 | 50.45 50.2 | 48.45 | 91.2] 75.70 91.2| 78.7 91.2] 78.20 91.2] 77.45 91.2] 79.95 91.2] 79.20 | | 22.5 | 25.25} 23.5 | 25.00 | 23.0 | 23.75| 22.0 | 25.50] 22.5 | 23.70| 21.0 | } } 51.45 46.5 | 50.45 45.5 | 49. 20 44.0 | 48.20 43.5 | 50.70 46.0 48.70 44.0 } weoececcecece fee we re a eet Rot 75.45 | ai 77.95 71.0 77.95 71.0 2 eee eee 76.70 69.5 80.20} 72.5 78.95 | 71.5 tte ee eee eee eee ho bo ose oe bo ro oo ne) H- bo ho OS & wow 6.2 | [rp 8.0 ra Rete ee 7.3 11.7 11.3 39974 = ee eee 558 | 8.640.587 | DAT ee. Deo Rane 9.5 9.6 10.4 Ga 1c: = eee 9.7 9.3 9.8 SY 7 fy ee .585 | 9.74 .095 A fs hep ERA 9.1 9.0 9.0 iO eae 9.5 9.6 9.4 SHAG os ogee .399 | 9.8+ .067 | B77 Cee hae eT —I-I=1 or or or Noho TO EEE MOISTURE CONTENT AND SHRINKAGE OF FORAGE, 9 TABLE I.—Comparison of different-sized samples of forage—Continued. SECTION D.—FIELD-CURED ALFALFA COLLECTED AT CHICO, CAL.—Continued. Weight. Moisture. Sample. Orig- | Inter- ard Oven Original Air-dry Lost in air inal. | mediate. Ty dry. material. material. drying. Ounces.| Ounces. | Ounces. | Ounces. Per cent. Per cent. Per cent. INOMD43 Se cme Sasa 114.0 96. 25 99. 00 87.5 OR} 11.6 13.1 INO 04 Ae eas eee 116.5 105.00 105. 75 94.25 | 17.7 10.9 9.2 NOt O40 te ee eee 115. 25 101. 50 102.75 91.75 | 20.5 10.7 10.8 IRENE 0) 085 SER eal Reh coe Is saci crc | BS OSNe eae Meroe: 2O2b Oil eae eee Keser sa mee NOs D4 GH pee acon s 115.75 100. 50 101. 25 90.00 | 22.3 12, 12.6 INO 547 Ee Seen 115.75 96.75 97.75 85.75 | 21.0 12.3 15.6 NOM OASE eereccine ara 116.25 92.75 94,00 82.25 | 29.3 12.5 19.1 ME Necntohsweren aren tiiecc om ey | a SAO OT ee ee Geen Mean onGseeeeeulce ee clese ee 2a Pa Ne Silty caare| MRE a eye 22.44+1.454 | 11.54 .186 13.44 .089 HETROT OL eae er ya Risers ate | RPS u EE ASar Geeoncee SD AQ Di Le aes CENCE eae a eet ea SECTION E.—GREEN TALL OAT-GRASS AND ORCHARD GRASS! COLLECTED AT ARLINGTON FARM. [Dates of weighing: Original material, June 2; intermediate, July 3; air-dry material, July 18.] INOS Ae et ct roceres 64 22.0 22.5 19.0 70.3 15.5 65.5 INOS 4 De oes ciclo 64 2155 21.5 18.0 71.8 16.2 66. 4 INGORAS a eee 64 22.0 22.5 9.0 70.3 15.5 65.5 Mean rol Sit sae eevee cm cee bee bms cecieec ch veeeees (Dice UN (is ane eae Aue ets SAA eoe ama ete INO AA ae A eras 64 22.0 21.5 18.0 71.8 16.2: « 66. 4 INO SAD eeroactacracise 64 21.5 22.0 18.5 Talal 15.8 65. 6 Meanyo idsecrener rr | ae ace al Sele elec lo om wisisiclse aillevec ms memes Uh Ose Sia oer enel Gosia woe were IMC aTIKO home eee oe reece csihstcioe| ee eicie aes wel os neememiee G1.1+4 .203 | 15.8+0.095 65.940. 129 ETT OTC fe ae eee Spee lope ln earoestsleal ree ois S siete = Sos Sociales SENG BH lal SSNS > Rael a ans See a IN OMAGH S Sen osc ce aie 128 45.5 46.0 38.0 70.3 17.4 64.1 INOMAT eet ee ecmce tics 128 43.0 42.0 35.0 72.6 16.6 67.2 INO A So Nas cpsroernceieterereS 128 43.0 43.0 35.5 (PAP 173 66. 4 | Nae GRBs a Se ly (isle eam emer FA Tg 0 oe a eee eee | IN@s402 06h dce seen 128 46.5 45.5 Bia eR 17.5 64.4 NOH Oee oe caceeiace 128 43.0 44.0 38.0 71.9 18.1 65.6 | joLEeon Gahan A led ee es. na | WY [SE HTOV COSC SS ee SU beens ee A Nea Pee NN Fe 1 C Z1.5+ .268 | 17.44 .145 65.5+ - 353 EST OMA fel erste roe ee sketornral| ermnorcrs a | eiecieinicine widille co seems SPER OO seo te co ee eee ee aes angie os. 128 46.0 48.0 38.5 | 69.9 190.7 62.5 INO HD 2 See reo cin os 128 46.5 48.0 36.5 71.5 23.9 62.5 NOMS See icien eis wooo 128 43.0 42.0 34.5 73.0 17.8 67.2 INGA INTO (7S ipeteeraraes cee cig elias om Sea Rea whieecec lees cdceen Tt ae es ROR al Pe Ns Se see [ee eee Noustecsa 128 47.5 47.5 38.5 | 69.9 igvomer oe uieeoss INOMOD acirsetemiecaes 128 46.8 48.0 39.0 69.6 18. 7 62.5 MTC SINE O hs seperate otal rate sreisioic ll oe eieieeinie sis [lows Baines FOES Oi eee se eee Gee en Se Mea noivo ner asererlrest a accelocben aecos| ccc cece cte|accsisesmas 70.8+ .391 | 19.8+ .204 63.54 .558 BOO lal eae ees tre sara ricins eee Oals che cos allaccaetauee APS onn| tea nicotene eee eee INOW Ose rese ote ces 192 63.0 65.0 53.0 72.4 18. 4 66. 2 INO: Laseae ees 192 65.0 64.5 53.5 howe 17.0 66. 4 INO Anos Se eae ener 192 63.0 65.5 54.0 71.9 Mid 65. 9 PIANO le Seer tess oilers elas icin ees eriewice Cesflas cs cmmees ADA NTE DoH LER car MA or I Re 9 Te ei INO) [ae Se eee 192 63.5 64.5 53.0 72.4 17.7 ey 66. 4 NIOSGO Resa stershe ee 192 63.5 64.5 53.5 72.2 17.0 66. 4 INEGAMTO eee alone | Hite Soa eE Ee ce caavees FA OTEK Vahl sa Plas ts el rele car ay ed Saye NMSA TNO [eee eet es etal ste crc aloes cs cio or Wo c cee ie 92.2+ .056|] 17.5+ .157 66.3+ .060 PEEL ONEO til Meese al eee ere eae ee ek ee BP PAID AL haya leere Aces [Eco Rak eye joey ean 1Samples 46, 47, 48,49, and 50 were cured in the shade for comparison with the other group of 8-pound samples which were cured in the sun. 21216°—Bull. 353—16——2 10 BULLETIN 3538, U. S. DEPARTMENT OF AGRICULTURE, TaBLeE I.—Comparison of different-sized samples of forage—Continued. SECTION E.—GREEN TALL OAT-GRASS AND ORCHARD GRASS COLLECTED AT ARLINGTON FARM—Con. Sample. Weight. Orig- Tnter- F Oven inal. | mediate.| A 4tY-| ary. Ounces.| Ounces. | Ounces. | Ounces. 256 83.0 82.8 68. 5 256 83.3 82.8 68. 0 256 88.0 89.5 (B50) 256 84.5 82.5 68. 0 256 led 78.0 64. 0 Se ei OG Ds Se ee Moisture. Original Air-dry Lost in air material. material. drying. Per cent. Per cent Per cent. 73. 2 764k 67.6 73. 4 17.8 67.6 The 83 Ze 65. 1 R226 4-8 2369 aeicc ce cos Se eee 73. 4 17.6 67.8 75.0 17.8 69.5 Cae COO | ancien cee eee 73.0+ .355 | 17.64 .079 67.04 .424 He. FOS sec. hee se |e ee SECTION F.—FI©ZLD-CURED TALL OAT-GRASS AND ORCHARD GRASS COLLECTED AT ARLINGTON FARM. [Dates of weighing: Original material, June 6; intermediate, July 3; air-dry material, July 18.] INONGG2E eee ce one oon 32 26.0 26.5 22.0 INON GUS eee Ok ekoa seen 32 27.0 27.0 22.5 INOR 68a blaze 32 26.5 26.0 21.5 IE TORO Ea eS Sol ocuerers| letersi ses| leansteoreri sis Guess oe COC ee INONOQ Hee eet aoe eee 32 26.5 27.0 22.0 INCOM IR ae eee ome 32 26.0 26.0 21.0 JW IGE ROO) Loree Berets ersisroms al merar i tcaal Mere Ome G Seon cero du (ete Wabe(O) tea ns ees eer Pee menor AA ERASE es ©) Lee ani eR eS Le ee TET OL ZOLA 0 epg ge 8 | eect epee peter sae Meee CH ie ANC ag A so INO Ries a es esc are ee 64 53.5 SPA 5) 43.5 IN Obi. A Seu SGeA AOR eee 64 57.0 57.0 47.5 INOS coho cists cere 64 53.5 53.0 42. 5 Mean Of 3 ee eee el bee en ll Deven teenie = collie dS ec None 64 56.0 55.5 46.5 INORIGias an oHee Seeeee 64 56. 0 56. 0 46.5 WaT OES ee a a eal fee ela erases | Ble 8 eas il i Jul IC ECO Rts Pee Pees pe [acme al MRS bas ay aed. SES een ROT. OL ee eS Ss | res eee Ef Bec | ee NOE (ea mera sora 96 84.0 82.5 68.0 INCE AOU Rees Sees 96 83. 5 84.5 70.5 INOS Set sk saens seneewe 96 83.0 82.0 67.5 ROA TNH OLED see rere a eee A INOELO aera 96 83.3 83. 0 68.5 INOS ROC Peete < Seislettere 96 86.3 87.0 72.0 Mie amiOtige aie saline ear | ea ele eee | eS ee eae A ete OW 0) Set nas ne earn FS RR CON | Lee RN) sabe OT EORO LE 1 ey. 2 ol Cai pee Chai a (pe eu ee INOS lien a 2 maiets 128 113.0 116.5 93. 5 INO: Stee sete 128 116.5 116.5 94.0 NON SS ce es eee as 128 115.0 116.0 93.0 Mieanvol 3 caeiscea ee ea ere see bers ic:cis tor Pees INOW 84ers eee 128 114.0 114.5 93.0 INO S50) eee cee asi 128 115.5 115.5 93.5 Meany Of Saale Sela eect als a et Ii KeFoh OOS Ua ps a eegpnee I ecm e cals | Ss 2 Taare | meats eA ee STOR IOML Sods Aligtes Uae abl nh a ae WO pes ices |} A Voc acy 31.2 16.8 17.1 29.7 16.6 15 32.8 - 17.3 18.6 $t.24.0.488) 3 eee 31.2 18.5 15.5 34.3 19.1 18.6 SOUSA OSes be Ul ee oe 31.8+ .409| 17.7-40.295 | 17.1+0.418 Ben GUA AN cae ie dees, aA I REE 32.0 24.3 17.9 25.8 21.6 10.8 33.6 19.8 17.1 30054-1310, |e ee | 27.3 16.2 13.2 27.3 17.7 11.7 99 Aa TBs ce eb |e ae 29.2+ .750| 19.94 .861} 14.14 .863 1 OU. ec e e 29.2 17.6 14.0 26.6 16.6 12.0 29.6 76 14.5 O8.ba SIS |e Se Se ee eee 28.5 17.4 13.5 25.0 17.2 9.3 DRT 764 fon see 27.84 .522| 17.84 .112] 12.74 .566 1. 167 |e cok. ee 26. 9 19.7 9.0 26.6 19.4 9.0 97.4 19.8 9.3 87.0 . 1297. en ee ee 27.4 18.8 10.5 26.9 19.1 9.7 OT 04. 0030 Nene en a ee 27.24 .136| 19.44 .113] 9.54 .169 BOA ex. sconce cracelt ee ae MOISTURE CONTENT AND SHRINKAGE OF FORAGE. 11 TABLE I.—Comparison of different-sized samples of forage—Continued. SEcTionN G.—GREEN TIMOTHY COLLECTED AT NEW LONDON, O8IO. [Dates of weighing: Original material, July 10; intermediate, Sept. 2; air-dry material, Sept. 28.) Weight. Moisture. Sample. . ‘ Orig- | Inter- Air dry Oven Original Air-dry Lost in air inal. | mediate. : dry. material. material. drying. Ounces.| Ounces. | Ounces. | Ounces. Per cent. Per cent. Per cent. INOMA0 I ee csee -aicmee 33 31 26.5 | 58.6 14.5 51.3 No. 402..... Rane alaisicis 67 33 32 2755 59.0 14.0 52.3 INOs403 eee coe ees se 63 32 31 26.0} 58.8 16.1 50.8 IMeammonosie ence |sosaeccelpoctee nate balbaSacseweel se namie ee 9938 ON 068s Rese ae oe octal so masse sae eos INOS 404R Ee sackcoccsae 65 33 33 28.0 57.0 15.1 49.3 INOS 40 Sac cins ae ciccteics 64 33 32 27.0 | 57.9 15.6 50.0 IN ON 40 G Secisicisre tie icis'esare 68 35 34 29.0] 57.4 14.7 50. 0 IMeaItOonoracncccsc| sacns ces aces siscccs soc esececc|s ccumeeces CTY fs a ee 2: 0 He rea ee Ot INMGATONG Gre ee nee sce leccaccne onset wees Bere ae eee 58.1+ .204| 15.0+0.192 50.6+0. 272 HE PLOTOle ee cecslescemcceles sce wees Sdeoeeeels esceuenes x ere: 9! 1) Pesos aeeepemietal hates © he else ot INONAD seem cece secce 134 67 66 56.0 | 58.2 15.1 50. 8 INOEA0S Se Paeiccielesinieieie(s 131 65 63 ago) 59. 2 15.0 52.0 INOS/4 09 Raias cintonleciarciaiase 131 65 64 54.0 58.8 15.6 olst WESTOVER Ssocueel HSS Sosecocses Bens SERCH BESRootsc DS se avietl OUR: Breas Cerra ic | Bete seers INON4IOs. ceceteeces Co: 0128 67 66 56.0| 56.3 15.1 48.5 INOR4TTE Cassa ccteincioce. 128 68 66 56.0 56.3 POSE 48.5 INE 42a ee as = ate sierats ere 128 66 64 54. 0 57.8 15.6 50.0 Mean settee hee eos sl Le a Bee oe ee eee MCAT OR Gee merase | hs cist cse loinc erstuvete s [ewis siaclesre | sod oo emmer 57.8+ .310 | 15.8+ .070 50.2+ .359 IS TEOTOL oe mw cteeewe se ac o coc las oe oslo cislo cieesiceieicic less ajmccreers ame (tal sss elses es es se oe INOFA4ISeeee nace cececs 195 100 98 83.5 57.2 14,7 49.8 INO 404 noe a Giercs cas 192 97 95 81.5 57.6 14.1 50. 6 INOS. Saas cee 192 99 97 USB!) BYE 15.9 49.5 IMGAINONS ee acecioeil se ce ciacte [cecwcs se cc siaie ose Gecul le edesyectine Deere? SOCAL Emsstcers ecice [Mon cts eee re INCOM 41 Gi icrrsceeeaercees 192 95 93 79.5 58.6 14.5 51.6 INOSAI ERS Soe hese cu 192 96 95 80.0 58. 4 LSSS¢/ 51.6 INOS 41S eee tucckibawces 192 96 96 81.5 | 57.6 Wet 50. 0 | Mean Olessas sacn |nuan cine Pose cseiaa parece ection eswccrmmee DS eae e aol 08h rakes ta. aaa Soa Ree eae MBN OM Saaeac as Gsesecsd BESSES Sos GECCRECoae Alero ssc. 57.8+ .137 | 15.0+ .176 50.5+ .230 | HIPTON Ollees seen aioe ccseetlecescceen eee SSRI cs Waa eR SOD eee e ere aa eee eae INRANGE See ce see 256 128 126 107.0} 58.2 15.1 50. 8 INOS 420 Beucneeoe ose: 256 126 123 105.0 59.0 14.6 52.0 INO M42 leriecciniclontatcias's 256 130 127 108.5 | 57.7 14.6 50. 4 IMCATN ON a sae ness cc seecec wc sence ccs as leccasdssec|sesceatiscs Seep her QOS eevee snc nen eect NG. eee 256 126 125} 105.0] 59.0 16.0 EES ING) 2 08 ee ie a eee 256 126 126 105.5 58.8 16.3 50.8 INQRAZA tetas cee occ 256 130 129 109.0] 57.5 1535 49.7 MeaIn Oita stecctense sonic cisclc lose cecuwcsloc cocces cc|eaboesmens BS eas, 260 Sweetie swe Scene me Se seca Mean of 6....... Baral eres iat icte | iets =a retools [is crtawiciesics [oc & sorte 58.44 .167 | 15.44 .179 50.8+ .194 ET TOTO Ieee a I mats cic cise ciscicieate |b wc ciwinic co s| cece ancien SEAT Oilaets aco cte searorssrahateeec oe ewes SECTION H.—FIELD-CURED TIMOTHY COLLECTED AT NEW LONDON, OHIo. [Dates of weighing: Original material, July 11; intermediate, Aug. 27; air-dry material, Sept. 28.] INOSA Dees onc 3 oe 32 30 30 26.0 18.8 13.3 6.3 INIOY 2 OSs Seen ee ae 32 30 30 26.0 18.8 13.3 6.3 INOS 227 (sae a ee 32 30 31 26.5 ME? 14.5 352 MeaaTO loiter aera aes iste | cicte =e ceotiste (nec Cieicicac os oe cae ee TS BY ASV UN [ear eat as | es ae INO 34284 nee oe 32 30 30 25.5 20. 4 15.0 6.3 INOSADS Ree sacri e.. 32 30 21 26.0 18.8 13.3 3.2 INOSAS0 Ge Sones once 32 29 30 26.0 18.8 13.3 6.3 WONT OTBE BSGSCCE| SASS E les ae | ene eee ce (noe ret Se 2947 | ios aeons eae sanoeene IMPOR THON Gaerne ee ee pec ere cea acs oa. LW a ee 18.8+ .254] 13.8+0.192 5.3+0. 402 ETE OUIO lelery eee eerie a siein ee re cme, os a) Car TE TAY S yal ee eM ey sok ae oe 12 BULLETIN 353, U. S. DEPARTMENT OF AGRICULTURE, TasBLe I.—Comparison of different-sized samples of forage—Continued. SECTION H.—FIELD-CURED TIMOTHY COLLECTED AT NEW LONDON, OHnIO—Continued. Weight. Moisture. Sample. Ori -_ 5 atc g- Inter- . Oven Original Air-dry Lost in air inal. | mediate. Aur dry. dry. material. material. drying. Ounces.| Ounces. | Ounces. | Ounces. Per cent. Per cent. Per cent. IN ORAS Terres See 64 59 60 51.5} 19.6 14.0 6.3 INOS 432 Sere ee eer 64 59 59 51.5 | 19.6 IDE 7.9 INN 433 5 sess eee 64 58 58 50.0 | 21.9 13.7 9.4 Meaniof3 ven. occ |ee eG asese| aslseenioces nie ele efelaie oe Sieioniiesiee 20°44 422 Fe: 225s Ler A eee INO Zee Ob ae eae 64 57 58 49.5 | 22.7 14.6 9.4 INON4 SDR is Sac nese 64 58 60 51.0 | 20.3 15.0 6.3 INOSAS6 Sasa See 64 59 60 51.0 | 20.3 15.0 6.3 Du eY25§ U0) Re Hage iat FA LE | FS a IPD a ek re ee ON ERs SAA QU SHWE eck bse a a eae eee IMCaTiONG os sees oes Sap oe leer era ea err on a cteerepeneees 20.74 .3821 | 14.24 .224 7.6 + .384 TESTOR OL tee er etc | or eA Ee ee bo SE OOM Ae oie Ree Ce eae INGSAS TARE Sati tote 96 87 88 (deo e\ 2184 14,1 8.4 INTOWAS Shenae tee tet 96 88 89 75.5 | 21.4 15.1 Uae INIOS43 Oa aie Re ce yee 96 89 88 75.5 | 21.4 14.1 8.4 MGATINO ON se eee ee sone eae Sie ee ere ere a] ae eee ao cll oer 21.4+ .000 ieee cette ean IN(OS;4 4.0) ese espns renee 96 88 88 76.0 | 20.8 13.6 8.4 INO 442 ae eee ae 96 88 89 75.5 21.4 15.0 Hoe INGO 57442 eee a ete ne 96 85 85 0} 24.0 14.1 11.5 VEC TUE Te eI RN oe ce ea ea Ls U8 aa aaa ee mage PO Mabe AT lie eae at SR Xt pe rae ere UOTE a VECO PGBS ae Meg Ol eR eh eee Ua ete ae 21.74 .285 | 14.38+ .148. 8.6+ .388 TTT OTL Leb seals 2 ear (raph eae yl sy aly oreaee ccd ey MOO ate RP RRC ee LS ee SOOT RV RNa ee he eee INONAAS ee neti eee 128 118 118 101.0 2122 14.4 7.9 INOS AAA Ne yn Meena 128 118 117 101.0 PAL 73 13.7 8.6 INO AAD Sea eee 128 118 119 102.5 | 19.9 13.8 Up IMO ATO TS esa Sse eee yan eyecare | enare ee ec en ele 20 8 se 289 ee eo oe eit ee hs ON ne nme INOS ZAG EEN ireckp sg itueles 128 119 118 101.5 | 20.6 14.0 7.9 INOS GUYS SRM ey ON 128 121 122 104.0 18.8 14.7 4,7 INO 44S eae 128 120 120 104.0] 18.8 13k3 6.3 IVECO TONOT ae reese eae eal eee oy Eee re Lar nce st aon ae 194? SOU Se re eI Se epee Wi EXE 50) 4 Gnesi aa PN ya aN Le aac. | nara 20.14 .277 | 14.0+ .127 G24 .354 GT OL IO Lads ye Pal cea ee eet ie er a er ae Ue on ela aS ey ee OTB ost eee eee Ree ACE SECTION I.—GREEN RED AMBER SORGHUM COLLECTED AT AMARILLO, TEX. [Dates of weighing: Original material, Sept. 4; intermediate, Dec. 5; air-dry material, Dec. 16.] NOR? OLS Snare 64..0 32.0 25.0 GSS aleaee 34.0 60. 9 INOS 202 Fee ee eye 65. 0 32.0 25.0 15.5 | 76.2 38.0 61.5 INOB203 eRe eee een. 70.0 35. 0 28. 0 19.0 | 72.9 32.1 60. 0 Mieamona rece se ie eee eva ee OT US amy | eran vo T4430. 528 toed ce INOA2 OF eee rs ee eine 64.0 34.0 27.0 16.5 | 74.2 38.9 57.8 INO2 OF i aera teen paers 72.0 40. 0 33.0 22.5) 68.7 31.8 54.2 Mea rots S35 Seo SURI RS EL AE eT ore eo eee re B19 19897 (ose dc Lee eee eee AW SYS OLC0 Gya pe yee SL gon Se ea Jp are en ee ae eI BG lacie, 93.2+ .516] 34.8+0. 894 58.9+0. 801 Ty iko) en 0p Ua Lancy eeseaests| s wearin oe [Pte Peas i Penney SANE 3. ies esos 41. DOS oso Seek ES | eee coe INONZOGREE eee ee 137.0 73.0 65.0 39.0] 71.5 40.0 52.6 INIO2 O(a re sire ees ai 128.0 64.0 55.5 SH 78 36.0 56.6 INOEZ08e Stee eee 136. 0 76.0 66.0 40.0} 70.6 39.3 51.5 Meamotis: ese 2 5 |S spe scts |pciseisemiere lc ela cie cae ioe oe V1.5 %2705|.2 oe eae eae eee ee IN'OM209Fe er esee eee 139. 0 72.0 64. 0 41.0] 70.5 35.9 54.0 HA (C0 77411 0 2 ie ere ete a] Ee rd a RB ee a So) ae | Pe ils SUSAN Sint CAM AS ee A Sai aCe Meant ase 2 2s |e eae eke oa |_ o's Se etm een pe eects Ren 91.2+ .248 | 87.9+ .630 58.74 .643 MEY PROLIO UL yoy patere crater ie tate eels toratoleleiciallla ere aictereterera | Ee ae petarereer A QAN es eke aeRO ese Cee NOs 2 Ue ete pase 204. 0 110.0 100.5 61.0} 70.1 50.7 INO 22 eee ia oe 192.0 96.0 87.0 SRG || TPT 39.7 54.7 INOf 213 Se eikekeeesoee 200. 0 110.0 100.0 61.0] 69.5 3 50.0 WW HRS BA SOA SAE ASCE ob ol ao MASc ASE ME caer sssstaqoae 10.82) 542 [hoe Se a era 1 Sample injured by mice. Ee MOISTURE CONTENT AND SHRINKAGE OF FORAGE. 13 TaBLE I.—Comparison of different-sized samples of forage—Continued. SECTION I.—GREEN RED AMBER SORGHUM COLLECTED AT AMARILLO, TEX.—Continued. Weight. Sample. Bs - a rig- nter- : ven inal. | mediate.| A 4tY-| ary. Ounces.| Ounces. | Ounces. | Ounces. INOS 2A Ree ee eee ie 196.0 106. 0 97.5 62.5 INQ); Cy Sees ae Se ease 202.0 104. 0 96.-5 61.0 IMeanvOnSoe yaa aoe adie ce eceenclsctoc oc cek | Sess IM CATHOM Deere eee ool eatericcicclas seslcicecle cc camer 1 Byg 0) P Ovid URE es ie ee ee Bee er |S ee Coe oe INOS 216 Sesae sess se 260.0 131.0 122.5 6.5 INON ieee eseecmeeee 258.0 131.0 122.0 78.0 INOS 21S 22 sea ecece see 260. 0 133. 0 125.5 78.0 MGA OLS area eala oes oats senna Selowa seeds waco cl ace mementos INOS21GRE ee See eee 264.0 139. 0 131.5 81.5 INOW220 Sacocs sce scces 262. 0 129.0 119. 0 74.0 MCR INO HSS ce ee ell aiee ce esta lace wiaaiatawtall aiccs wisieleios oe ctnctererect IMeaniGhoascese. as Ba mweniccnl nccitclesiowe sews tices owe temecen TOG Oe Eee ORS aS RS] MOSCCE COC COCCOOCEIe Heer scooare Original material. Per cent. 68.1 69.8 Moisture. Air material. Per cent. 35.9 36.8 Lost in air drying. Per cent. 50.3 52.2 ee ee ee SECTION J.—FIELD-CURED RED AMBER SORGHUM COLLECTED AT AMARILLO, TEX. [Dates of weighing: Original material, Nov. 9; intermediate, Dec. 5; air-dry material, Dec. 16.] INOM 22 eet enes ccecee 42 INOS 2222 hace cece c cess 35 ING 223eee cesses Soeees 37 No. 224....... Sasswees 40 INOS 225 steneeeeae wares 38 INOS226) 22 Sees cece 67 INOS22 78 eee nd ceSe8 <5 69 No. 228..... weeaekes ae 70 INOS 229 3st cssStcse? 70 INOS2302e to aoees css 72 INOE OSes. 105 INOe232ha 3 ee 104 INIQS TS SIA Se eee coer 102 INGE GRY heer a ee 104 INOB23 5 Sse enc oe en cones 106 INOBOSGG= 2 a SE: 133 INGs FBV S Sa eoe eee 135 INO 23S seo sence 134 INOSZEO ac SS ee 134 INOS 240 Bae ee Se 134 HMTTOROR W532 ae eee 31.0 24.0 24. 0 17.0 25. 0 18.5 27.5 21.0 26.0 19.0 52.5 35.5 54. 0 36.5 54.5 38. 5 54.0 38. 0 58. 0 44.5 87.5 62.0 85. 5 62.5 85.5 60.5 88.5 60.5 88.0 60.5 113.5 82.0 116.0 79.5 116.5 86.0 118.0 82.0 115.0 84.0 42.9 51.4 50.0 48.141. 450 47.5 50.0 46.44 .377 45.7 38. 2 44.64 .987 Se 14 BULLETIN 353, U. S. DEPARTMENT OF AGRICULTURE. RELIABILITY OF AIR-DRIED SAMPLES. The reliability of air-dried samples may be determined in three ways: (1) By a comparison of the percentages of moisture loss in the samples with that in the 100-pound and 500-pound quanti- ties, which, on account of their bulk, approximate field methods; (2) by a careful comparison of the relation between the moisture lost in air drying and the total moisture content as revealed by oven drying; and (3) by noting the variation in the percentage of moisture remaining in the air-dried material. A comparison of the moisture loss in air-dried samples with that in bulk lots of the same material is given in Table II. TaBLE IJ.—Comparison of the loss of moisture in green and field-cured forage when air dried in small samples and in large bulk. . . . Moisture in field-cured ~ Moisture in green material. aintora Place. Crop. Loss in | Loss in Loss in | Loss in Total. samples.| bulk. Total. samples.} bulk. Per cent. | Per cent. | Per cent. | Per cent. | Per cent. | Per cent. Chico Calecs see Minin ss2ck soe ae 76.9 74.5 73.0 22.3 : ink Arlington Farm, Va.-.-.| Tall oat-grass and 72.0 66.3 64.3 29.0 13.4 13.5 orchard grass. New London, Ohio...} Timothy...-....... 58.0 50.5 49.2 20.3 7.2 10.1 Amarillo, Tex...-...- Sorghum.......... (lez 54.2 58.2 43.2 20.5 16.8 PAV Se KanSerneeeen eeeee GO n see eeeeas|aee ccc eee 65.8 60:9) |oS2 oss 26.0 Pa | It will be seen that the losses in the small samples of green material, except for those of sorghum at Amarillo, Tex., which were not well cured, averaged from 1.3 to 4.9 per cent greater than it did in the bulk lots. This was to be expected, since the small sample naturally dries out more completely than the bulk. The difference, however, is shght, and the loss of moisture in the small samples seems to be fairly consistent with the loss which was found in the bulk lots. The comparison of small samples with bulk lots of field-cured material is not so favorable to the use of the sample method as in the case of the green material. Table II also shows that the mois- ture loss in the samples, when compared with the total moisture con- tent, is not quite so ree as the percentage of moisture loss in the bulk lots. A better way to Hetennne the reliability of the sample method is by a study of the percentages themselves, especially in the column devoted to percentage of moisture in the air-dry material. The uni- formity of these percentages throughout one crop means that the air drying of samples can be depended upon to bring samples to a nearly uniform moisture content, and this method therefore serves the pur- pose of correcting field weights almost as well as to oven dry the samples. The moisture content of the air-dry samples is not en- MOISTURE CONTENT AND SHRINKAGE OF FORAGE. 15 tirely uniform, but except in a few instances the probable error is quite low, averaging for over 200 samples only 0.28 of 1 per cent. With such a low probable error it seems entirely reasonable to depend upon the air drying of samples for all practical purposes. COMPARISON OF SAMPLES OF GREEN FORAGE WITH SAMPLES OF FIELD-CURED FORAGE. Summary Table III gives a complete comparison of the averages of the probable error in green and field-cured samples for the differ- ent crops as collected by six individuals. These averages include more than 250 samples of green material and more than 200 sam- ples of field-cured material. The best index to the reliability of these samples is in the percentage of moisture in the original samples. TaBLE IIT.—Mean percentages of morsture in forage samples of different sizes, showing also probable errors. SECTION A.—GREEN MATERIAL.1 Moisture. Sample. Crop Place Original iMGeide Lost in air ; samples. y- drying. Per cent. Per cent. Per cent. ACHOUNG e oeckine sete a aoe ale Sorghum..| Amarillo, Tex.| 73.24+0.516 | 34.8+0.894 58.9+0. 801 S-DOUNG mie asses sane cea oes Ieee GIDE NRA colisoaee doses 71.2+ .248 | 37.94 .630 53.74 .643 PPAWOUNG eects cok enn = cae oan leas Com eeeraleeae dose erere 70.14 .451 | 38.14 .476 51.64 .523 NG DOUMG sere es poet onic asics s cicie CWOSER asa Gaaee dowenaaese 70.84 .274 | 37.54 .209 52.44 .437 IMGa rete sere oe oa eens oan 5 hc e cameo eros 71.2 37.1 54.2 A= NOUN Ms Sees eee eae ais cate cioreis SORT NbN S|) EWE GNIS Golacckccoacccocdl keeboecceaboes 66.94 .526 S- POUR GE. eres see oes ete wic'cis fierce CIDER Neal ezene GO eee ee rrpa Seats | eras ote wescte crersiee 68.0+ .296 PETS OUI aoe See es Sasi saints cleo s| sine COseesecllanoac GO Aaa Rae Sosa clnces caminet 64.94 .289 1G POUN Cassette em arises sae GOR oes GOs seers ease ssid acis| ae Sec smc ce 63.44 .393 HMA eh r epere paper ate aya ata | etree cloeai| i oie ate o atole tae Cee Oe che cette oleae cecmiae omar 65.8 oo ee” ADOUNGe ee Scene semi ae saci Timothy... ee London, | 58.14 .204] 15.04 .192 50.6+ .272 io. S_POUNG se eee se ee eas wc GhOges 284 eames doses: 57.8H .310} 15.34 .070 50.2+ .359 1 2=WOUN Cee anes eee aciae Se wiee SeiliciS GOR eee Cossaeee 57.84 .137 | 15.04 .176 50.54 .230 PBS UE een | Opal cetere dose 58.44 .167] 15.44 .179 50.8+ .194 IWUGITN Se See Ae Beas Hie See ea tn 58.0 15.2 50.5 AM TVOUG eee eee ce ne cis aie Se Tall oat- | Arlington, Va.| 71.14 .203 | 15.84 .095 65.94 .129 ass. SeWOUNO Rare Ber ee ee eo AG Bee at CO seas ee 71.54 .268} 17.44 .145 65.54 .353 PP POUN Gest tees. ses aot ence Coe rae ee dose 72.2+ .056} 17.54 .157 66.3 .060 TCS OO ING Ao ee ee ee eee | er GO easalae es COs 73.384 .355 | 17.64 .079 67.54 .424 INTO Tine tte ee Meee eho cre nei il eras sis ore SSE 72.0 17.1 66.3 ——— a SS SS SS ae CHAO MIG las ce ones a aera aEeee oe Alfalfa....| Arlington, Va.| 74.0+ .344| 10.74 .517 71.04 .237 SOUN GREE Sete a Sai Ome | Maes dO eee 74.8+ .225|} 10.54 .129 71.84 .257 TOA ODL NAY G Ls ap GO eee ee ee (6 Koya Fe 75.54 .160} 10.94 .107 72.54 .136 NGA POUNG a see ee ccs cleo we GO een eae doi: 76.54 .155] 10.84 .251 73.64 .155 Monneteeren ec KOT Oe as 75.2 | 10.7 72.2 ASNOUNGer meee enc ee) Be ET Alfalfa ....| Chico, Cal..... 75.14 .258 7.64 .253 73.04 .249 SOLEIL See ee cn os iain Se ete Sa we (OKys Aaa aaa Goiaseeee 76.74 .234 9.84 .407 74.24 .258 O-WOUT Cie fasten oe ey sacle ee GOs saat leeece dO: ee 77.74 .129} 10.34 .113 75.2+ .144 TGS OYOTTING Fh cts Gas BG See ee eee ee Goya |S so dO. eee 78.04 .109} 10.2+ .098 75.44 .108 Ga Timer retin res ony (Se ynte PAG HG MR os eae ee 76.9 9.5 74.5 1 Average probable error for the 4-pound samples, 0.305; for the 8-pound, 0.257; for the 12-pound, 0.187; for the 16-pound, 0.212; and for all the samples, 0.240. 16 BULLETIN 353, U. S. DEPARTMENT OF AGRICULTURE, TaBLE III.—Mean percentages of moisture in forage samples of different sizes, showing also probable errors—Continued. SECTION B.—FIELD-CURED MATERIAL.! Moisture. Sample. Crop. Place. Original eels Lost in air samples. y drying. Per cent. Per cent. Per cent. 2-NOUNAK 2s 2 see EEE E ER Sorghum..| Amarillo, Tex.| 48.4+0.812 | 25.510.712 30.5+0. 694 A-NOUNGE eis Hae ee eae alee | ae GO: 2 ace a|ceeer Goss Sacks 44.64 .987 | 29.34+1.003 21.54 .351 G- pound S23 Sexes gests se eet | Ses Gow See WoOstes has 41.3+ .300 | 29.74 .515 16.5+ .281 S-pOUNGL tes et eeae se eee See (a Koes Recs se Cece 38.3+ .528 | 28.64 .617 13.6+ .290 Mears 28 si see Bone nape oops iM Ay 2 em eee ACs ee ce ae 43.2 28.3 20.5 2-POUNGA = Oh2a. aoe Rees Sorghum...) -Hays, Kans*. .|22 22-26-22 seleeee eeeeee 26.9+ .952 A=WOUTG! se. SS eR ERE en eh ee is Goss eral e Gogh: 4. ESE eae: | Pe cee eee 25.04 .432 G2 POU Ee a Le eet ore yes dots 2c2|22e COs 2s ash cheiscieee eee a5 | eee eee 26.94 .422 S-pOUNG eG cect epee ee eeesee ee lees dere ee lac cits (0 (Re EN eps I ee | MEE RAIS 25.04 .302 Mean nis nk at ea oil ete oh Soe shee ed IE rg ee 26.0 DOUNG LHe cc sesaceee cea caa ee Timothy.-| New London, 18.84 .254 | 13.84 .192| 5.34 .402 io. A“ OUNG? eee Sa ots ee ee ee ga doses asses dos earn 20.74 .321] 14.24 .224 7.64 .384 G= POUT ee ea se an ee ae GORe es Soe Ore ee 21.74 .285 | 14.34 .148 8.64 .388 S-pounds 2.2255 See ee elacs dos. 2heclessz2 dosioea.4 20-14 .277| 14.04 .127 7.14 .354 Meant or sare si Gated aceite onstrate Sa 20.3 14.1 7.2 2=NOUNG eins shi see ae eae eee Tall oat- | Arlington, Va.| 31.84 .409 | 17.74 .295 17.14 .418 grass A-DOUNG A hos thea eee Operas qos 29.24 .750 | 19.94 .861 14.14 .863 G- pounds. Sassen ao ons doses 's|o258 doe. ce se 27.84 .522 | 17.34 .112 12.7+ .566 | S-POUNG yachts eee ea eee Te GOS ee ee Ol ererems ace 27.2+ .136| 19.44 .113 9.54 .169 iN CA ee alate caah Sol glee a Megiared a hak Pease. Alan 29.0 18.6 Eee oe NOUN Se Sr eee a le ee Alfalfa....| Arlington, Va.2} 9.04 .193| 9.54 .045 |.............. AANOUNG acs cco me ee el nee (0 oes Sere a Co aa ies ere TO; 4-= 099)" 10082 5203s lo2-coeeee eee G=pOouTid er oe eek eee ere ens GOs ee | sees dor ees 12.34 .257 QO) 432° S156 Wea cce teers S-NOUMG Sears seemed ae pee cal ere Co Kote 250s eee Osea 1210220. 1815 1d 03> 235) beeen 10 C2 Bagel oy ag ge a eae = ears S| (ana 2 ens Al PMS A Aero Parl MSS woes 10:03) 5 os See 2-POUNG eas Seek eee eeaeihe eee Alfalfa ....| Chico, Cal.-... 20.6+ .558 8.64 .587 13.2+ .611 A-DOUNG eins: ts ae eeepc a tose ee Goze reenter Cosy yee 23.9+ .585 9.74 .095 15.94 .548 G-POUNGE ete See tea ee ee Ean GOs Aer cee (Oho One 22.4+ .399 9.34 .067 14.64 .452 S-POUNG eS o= fete acer thee acct lose GOs pase GOs a seee 22.441.454 | 11.54 .186 13.4+ .089 Moan) ott tree ih Brera: peel. | ean thas 22.3 | 9.8 14.3 1 Average probable error for the 2-pound samples, 0.445; for the 4-pound, 0.548; for the 6-pound, 0.353; for the 8-pound, 0.515; and for all the samples, 0.465. 2 The alfalfa at Arlington was cured in the greenhouse before the original weight was taken, so that the original weight is of air-dry rather than of field-cured material. The average probable error for the green samples is about 0.240 of 1 per cent, and of the field-cured samples 0.465 of 1 per cent. It | appears from this that the probable error for green samples is approx- imately half that found in the corresponding field-cured samples. In field practice, however, this difference is not so important as it appears, because the bulk on which the correction is made in the field-cured material is approximately half of that where the original green weight is considered. Much greater extremes, however, are found in the field-cured sam- ples than in the green samples, showing that even though the aver- age probable error is not excessive, still there is a possibility of sufficient error in these to affect the results when corrections are MOISTURE CONTENT AND SHRINKAGE OF FORAGE. 17 _ made with only one sample. Table II also shows that the samples of field-cured material are less consistent than samples of green © material when compared with bulk lots of the same forage dried under similar conditions. RELATIVE VALUE OF SAMPLES OF DIFFERENT SIZES. The figures on the relative value of samples of different sizes as given in Table III are not conclusive. There is a general, though not consistent, decrease in the probable error as the size of the sample is increased, but what would otherwise have been an expressive array of averages has been spoiled by the excessive probable error in the 8-pound field-cured sample of alfalfa at Chico, Cal. The average probable error for the 8-pound samples, including the Chico results, is 0.515 per cent; if we eliminate the Chico results it would be 0.281 per cent, which perhaps is nearer what might ordinarily be expected. It will be noted that as the green samples of alfalfa and of tall oat-grass increase in size, the greater was the percentage of loss in curing, as indicated by the column headed ‘‘Moisture in original samples’ in Table III. This fact makes it seem probable that there was a loss, by fermentation, of matter other than water, but such a loss would not mean an increase of error in the use of samples when the samples are of a uniform size. On account of the difficulty of curing samples of green forage they must necessarily be comparatively small, and when used in correcting actual field weights the samples, whether green or field cured, must be small enough to admit of easy handling. From the data presented in the table, it seems that the 4-pound field-cured and the 8-pound green samples are nearly as accurate as the larger ones. Considering accuracy, the facility of handling, the ease of figuring percentages, etc., 5-pound samples of field-cured and 10-pound samples of green material are recommended as the most desirabie for practical work. EFFECT OF REPLICATING TRE SAMPLES. The data on the effect of replicating the samples are found in Table IV, where the probable error has been expressed for single samples, replicates of three, and replicates of five and six. TaBLE I1V.—Average of the probable errors of one, three, and five or six samples. Field-cured material. Green material. Number of replica- grend aE ela G2 1. 8 Atenas 8 | foes | 162) lEAvers| ager pound.|pound.|pound./pound.| age. |pound./pcund./pound./pound.| ace. ae ct.| Per ct.| Per ct.| Per ct.| Per ct. Per ct.| Per ct.| Per ct.| Per ct.| Per ct.| Per ct. CAD SE Te A ee ee ee 1.006 | 1.243 | 0.818 | 0.994 | 1.015 | 0.686 | 0.586 | 0.407 | 0.486 | 0.527 | 0.777 athireetes o.8 2S ST 458 | .668] .397) .473 | .499) .331 | .277|] .156} .256] .255 377 Pivean@sixs ioc 25.22. 445 | .548 353 | .515 | 2465) 9.278 | .257 | 2187 |) 2212 )) .234 - 349; 21216°—Bull. 353—16——3 18 - BULLETIN 353, U. S. DEPARTMENT OF AGRICULTURE. Extreme care in sampling has kept the probable error very low on the single sample, so that it is nowhere excessive, but replicating the sample three times reduces the probable error 51.5 per cent, while a replication five and six times reduces the probable error over single samples 55.1 per cent and over three replications only 7.4 per cent. It does not seem necessary, therefore, in practice to replicate more than three times. Single samples, however, can not be considered safe when there is wide variation within the plat unless extreme care is used to make the sample composite and representative of the entire area. MOISTURE PERCENTAGES IN GREEN FORAGE AND IN FIELD-CURED FORAGE, AS SHOWN BY SAMPLES. Farrell, in an article in the American Journal of Agronomy,’ sug- gests the desirability of expressing alfalfa-hay yields in terms of green weight. In the article referred to above, he reports 76.5 per cent of moisture lost in air drying, which would be approximately equivalent to 79.5 per cent of total moisture. The average percentage of moisture in the 23 analyses of green alfalfa reported by Jenkins and Winton ? was 71.8. At Arlington Farm, Va., green alfalfa averaged 75.2 per cent of moisture in 20 samples. This percentage is probably near the aver- age for moderately thrifty alfalfa grown without irrigation in the Central and Eastern States. Alfalfa grown under irrigation and cut when one-tenth in bloom at Chico, Cal., averaged in 1914, 76.9 per cent of moisture. In 1911 McKee? found at this station as the average of 28 determinations in alfalfa not quite in bloom 85.8 per cent of moisture. The 1914 results indicate that the condition of crowth affects the moisture content very decidedly. Owing to excessive heat and scarcity of water, the alfalfa used for the 1914 samples was less vigorous than that of 1911 and correspondingly less succulent. These differences indicate very clearly the danger of basing yields on the green weight, as suggested by Farrell, or of using some arbitrary percentage of moisture in making corrections on the green weight. Samples should always be taken in experimental work when the crop is harvested and the amount of moisture in the forage at that time determined from them. Field-cured alfalfa at Chico in 1914 had 22.3 per cent of moisture, while Jenkins and Winton ” report as the average of 21 analyses only 8.4 percent. The samples of Jenkins and Winton had probably dried out to some extent after being brought into the laboratory. 1 Farrell, F. D. Basing alfalfa yields on green weights. In Jour. Amer. Soc. Agron., v. 6, no. 1, p. 42-45, Gio E. H.,and Winton, A. L. A compilation of analyses of American feeding stuffs. U.S. Dept. Agr., Office Exp. Stas. Bul. 11, p. 22-75, 1892. *’ McKee, Roland. Arabian alfalfa. Jn U.S. Dept. Agr., Bur. Plant Indus. Cir. 119, p. 25-30, 1913. MOISTURE CONTENT AND SHRINKAGE OF FORAGE. 19 The bulk of the timothy samples taken at New London, Ohio, in 1914 were overmature for hay, being past bloom and with many of the lower leaves dead. In this condition the green timothy con- tained only 58 per cent of moisture, but when cut at the proper time (in bloom) it contained 71.4 per cent. The timothy which contained 58 per cent of moisture when green contained 20.3 per cent when field cured. Jenkins and Winton ! report an average of 61.6 per cent of moisture for green timothy and 13.2 per cent for field cured. Meadow hay at Arlington Farm, Va., containing a mixture of tall oat-grass and orchard grass had when green 72 per cent and when field cured 29 per cent of moisture. Although the field-cured samples were taken after the hay had dried sufficiently so that moisture could not be wrung from the stems by twisting a bunch of hay in the hands, » still it was adjudged not quite dry enough to stack. Red Amber sorghum in fairly thrifty condition at Amarillo, Tex., had 71.2 per cent of moisture when green and 43.2 per cent when field cured. The percentage of moisture, though about the same as that of other crops for the green material, was much higher in the field-cured state. Undoubtedly this was due to the moisture carried in the stems. Jenkins and Winton ! report 79.4 per cent of moisture in green sorghum, but give no figures for the field-cured material. In corn, however, which should be much the same as sorghum, the average of 126 analyses of green material showed 79.3 per cent of moisture, while 35 analyses of field-cured material gave an average of 42.2 per cent of moisture. These results go to show that forage crops when ready to harvest average about 70 to 80 per cent of moisture in the fresh material. Field-cured material of different crops varies so widely in moisture content that the percentage to be expected in any one case can hardly be foretold. MOISTURE LOST IN AIR DRYING SAMPLES. Consideration of the means in Table III shows that irrigated alfalfa at Chico, Cal., lost in air drying 74.5 per cent of moisture out of a total of 76.9 per cent. Unirrigated alfalfa at Arlington Farm, Va., lost 72.2 per cent out of a total of 75.2 per cent. Timothy at New London, Ohio, lost 50.5 per cent out-of a total moisture content of 58 per cent, but, as shown in Table VI, the loss was 68.8 per cent when the total moisture content was 71.4 per cent; the mixture of tall oat-grass and orchard grass at Arlington Farm, Va., lost 66.3 per cent out of a total of 72 per cent; and the Red Amber sorghum at Amarillo lost 54.2 per cent out of a total of 71.2 per cent. At Hays, Kans., sorghum lost 65.8 per cent in air drying. This differ- ence is no doubt due to the fact that the stems of the sorghum 1 Jenkins, E. H., and Winton, A. L. Op. cit. 20 BULLETIN 353, U. S. DEPARTMENT OF AGRICULTURE. were split in the Hays samples, while in the Amarillo samples the stems were left entire. Splitting the stems when collecting sorghum samples greatly accelerates air drying and probably adds to the uni- formity of the dried samples. This practice is recommended in the preparation of sorghum samples for correcting yields. AMOUNT OF MOISTURE IN AIR-DRY SAMPLES. The amount of moisture in the air-dry material depends not only upon the humidity of the atmosphere but also on the nature of the matcrial in the sample. The sorghums, unless allowed to remain an extraordinary time under conditions suited for drying, retain a considerable percentage of moisture because of their large stems with the hard outer walls. Alfalfa, on the other hand, being quite succulent and leafy, loses its moisture rapidly and rather completely. Alfalfa at Chico had 9.7 per cent of moisture in the air-dried mate- rial, while at Arlington Farm, Va., there was 10.4 per cent. This difference probably represents the effect of the different degrees of humidity at the two places. Timothy at New London, Ohio, retained 14.7 per cent of moisture in the air-dried material, while the mixture of tall oat-grass and orchard grass at Arlington Farm, Va., retained 17.9 per cent. Sorghum at Amarillo, where the stems were not split in the samples, retained an average of 32.7 per cent. It is unfortunate that dry-matter deter- minations were not made on the samples collected at Hays, Kans., as this would have given an opportunity to compare with the Ama- rillo samples others in which the stems were split and the drying was much more complete. The above percentages no doubt represent fairly accurately the moisture percentages which may be expected in the air-dry samples of these different crops. EFFECTS OF DRYING SAMPLES IN THE SUN AND IN THE SHADE. To compare the relative moisture content of air-dry material allowed to cure in the shade with that cured in the direct sunshine, two sets of alfalfa samples were taken at Chico, Cal., and two sets of the mixture of tall oat-grass and orchard grass were prepared at Arlington Farm, Va., one set at each station being placed in the shade to cure, while the corresponding set was cured in the sun. The results, as given in Table V, show that while the total shrink- age was greater in the shade-cured samples at both places the mois- ture content of the air-dry material was a little less in the sun-cured samples at Chico and a little greater in those cured in the same way at Arlington Farm. MOISTURE CONTENT AND SHRINKAGE OF FORAGE, Pep’ TaBLE V.—Comparison of sun-dried and shade-dried samples of green material of alfalfa and of a mixture of tall oat-grass and orchard grass. Moisture, | Moisture, | Moisture Place. Crop. Treatment. original air-dry lost in material. material. | air drying. Per cent. Per cent. Per cent. Arlington Farm, Va....| Tall oat-grass and or- | Cured in shade. .| 71.540. 268 | 17.440. 145 | 65.5140.353 chard grass. HD ORS serene ie ee eee ee (AV SRG e ee A Cured in sun....| 70.8+ .391 | 19.8+ .204 | 63.5+ .558 Chico, Cal. NE a aes PAN alia wes Ss eh Fe ee Cured in shade. .| 75.9+ .267 | 11.64 .486 | 72.74 .314 Bowen, at os GOn eer ae ee Cured in sun....| 74.0+ .061 | 10.74 .180 | 70.84 .120 1 The detailed record of these samples is given in Table XII. Samples 549, 550, 551, 554, 555, 556, and 557 were cured in the shade; Nos. 552, 553, 559, and 569 were cured in the sun. The differences indicated in Table V are too small to warrant any conclusions, even if the results at the two stations agreed. It would seem, therefore, that so far as the moisture content of the air-dry material is concerned it makes little difference whether the samples are dried in the sun or in the shade. The greater shrinkage in the shade-dried samples was perhaps due to loss of dry material on account of fermentation, which might well be greater in green ma- terial dried in the shade than that dried in the sun on account of the more favorable conditions for the development of fermentation organisms. VALUE OF CORRECTING FIELD WEIGHTS BY THE SAMPLE METHOD. The work so far done in correcting forage yields by samples makes it apparent that the method is of greatest importance with crops that lose their moisture slowly, such as the sorghums and Sudan grass. It is also valuable in comparative work where the treatment accorded different plats of the same crop differs widely, or in a com- parison of varieties that lose moisture at different rates. The use of this method of correcting yields by samples, if it should become general, would be of much value in standardizing agronomic data obtained in different countries and different parts of the United States, where conditions affecting a crop during the growing and harvesting period differ greatly. | The use of the sample method and the differences which may be expected from corrections made in this way are well illustrated by the following results obtained on the forage-crop field stations in the regular plat work. Sorghum.—At Chico, Cal., the corrected weight of sorghum, as determined by the use of air-dried samples, was 41.6 to 47 per cent less than the weights taken in the field at the time of stacking the crop. This fodder was not as dry at the time of taking the field weights as is desirable, yet it may fairly have been called field cured in the ordinary meaning of the term. At Hays, Kans., the corrected weights, as computed from air-dried samples, average 20 to 30 per cent 22, BULLETIN 353, U. S. DEPARTMENT OF AGRICULTURE. lower than the field weights, even when the sorghum had been curing through seven weeks of good drying weather after harvest. The dif- ferences in field-cured and computed air-dry weights for different varieties and different dates of planting varied from minus 3.7 per cent to plus 31.3 per cent. It would seem, therefore, that maturity at harvest, size of shock, and succulence of the variety are factors affecting the moisture content of field-cured sorghum almost as much as different lengths of drying periods. At Amarillo, Tex., the differ- ence in the percentage of moisture in field-cured material of Red Amber sorghum and air-dry samples of the same varied from 12 to 33 per cent, while the total moisture in the samples varied from 35.8 to 55.7 per cent, as determined by oven drying. Such differences are enough in many instances to change the conclusions of the value of different methods of treatment or different dates of planting. Sudan grass.—At Hays, Kans., after Sudan grass had been cured three days, the field weights were 25 to 40 per cent greater than the computed air-dry weights based on samples, and there was 21 to 40 per cent difference after a similar period of curing at Chillicothe, Tex. Many of the phenomenal yields of Sudan grass and sorghum that are reported by newspapers can be explained in part by this excessive moisture content. Alfalfa—The computed air-dry weights of alfalfa at Chico, Cal., were 10 to 15 per cent less than the field-cured weights, while at Hays, Kans., in good curing weather, there was a difference of only 2 per cent. Different methods of culture affect the moisture content quite decidedly, as shown with alfalfa at Chico, where in the May 15 cutting the hay from drilled plats showed only 10.9 per cent loss in air drying, while in the 35-inch rows the loss was 24.3 per cent. Cuttings of alfalfa made at different stages of maturity can not be compared accurately unless they are checked by the sample method. The difference in moisture content of the field-cured material has been found in a number of instances to be as great as 30 per cent. Millet —Of all the crops tested, millet showed the least difference between the air-dried and the field-cured material. The loss at Hays, Kans., averaged about 9.3 per cent. RELATION OF THE STAGE OF GROWTH OF FORAGE PLANTS TO THEIR MOISTURE CONTENT. It has long been known that plants when young contain a larger percentage of water than they do when mature, but no great amount of data on this point, even for our principal crop plants, is to be found. A compilation’! of all the data available on this subject indicates the average percentage of moisture in alfalfa to be as follows: 1 Vinall, H. N.,and McKee, Roland. A digest of literature relating to the moisture content and shrink- age of{forage. In Jour. Amer. Soc. Agron., v. 8, no. 2, 1916. MOISTURE CONTENT AND SHRINKAGE OF FORAGE, 23 Height of 18 inches, 83.3; in bud, 79.1; early bloom, 77.8; half in bloom, 74.3; in full bloom, 70.6; bloom fading, 68.3; leaves drying, 65.1; fully ripe, 55.9. For timothy: Heads not yet visible, 74.4; heads just appearing, 72.9; heads fully out, 70.8; beginning to bloom, 66.7; in full bloom, 64.3; past bloom, 59.8; seed fully formed, 54.3; seed becoming hard, 49.2. Investigations on this point were made with the following crops: At Chico, Cal., alfalfa; at Hays, Kans., and Amarillo, Tex., sorghum; and at New London, Ohio, timothy. In the alfalfa several cuttings were made at intervals early in the season, so that later all the differ- ent stages of maturity could be secured on the same date. The same result was accomplished in the annuals by using plats of sorghum which were planted at different dates. The intention was to handle the timothy in the same way as the alfalfa, but such arrangements were found impossible, and the cuttings of timothy were made on different dates. Samples of all these crops were secured, representing approximately the following stages of development: (a) Very young, intermediate between the beginning of growth and budding. (6) In bud, before bloom began. (c) About one-tenth in bloom. (d) Full bloom. (e) Fully mature, seed hardening. EKight-pound samples representing each stage of development were taken immediately after cuttmg. Each sample was placed in a sack and kept for 20 days or more until it became perfectly air dry. The amount of moisture lost in air drying was then determined and the sample was sent to Washington, D. C., where it was reduced to a water-free basis in the drying oven. The results obtained with the different crops are given in Table VI, the averages for each crop being also set forth in a separate summary (Table VII). TasLE VI.— Moisture in growing forage at different stages of development and in the air- dry material. SECTION A.—ALFALFA SAMPLES COLLECTED AT CHICO, CAL. [Dates of weighing: Original material, July 2; intermediate, Aug. 19; air-dry material, Aug. 24.]} Weight. Moisture. Sample and jstaze of ay growth. et! Air | Oven! Original Air-dry Lost in air Green meat dry dry. material. material. drying. Rety young; 12inches high: |Ounces.|Ounces.|Ounces.|Ounces.| Per cent. Per cent. Per cent. 0. 58 : 9 7.95 24 80.5 14.1 = OF Sasa seansvosso ee 123.2 | 27.95) 27.95 .0 77 INDE Siecta- eo Secutee ce 123.2] 29.45) 29.45 26.0} 79.0 11.8 76.1 NDS S a eco. st 123.2] 31.70) 31.95 77.3 12.3 74.1 LTR oA a ne ee 123.2} 31.45} 31.45 28.0 | 77.3 11.1 74.5 i) Teel, OS Se eg Se 123.2 | 27.95) 28.20 24.5} 80.2 13.1 Cig! AN ELAY O ores ca csc h eel oasise foc|semeeccd ecwedcs<|eobteceoe 78.9+0.412 | 12.540.314| 75.8+0.395 ee 94 BULLETIN 353, U. S. DEPARTMENT OF AGRICULTURE. TaBLe VI.— Moisture in growing forage at different stages of development, ete—Cont’d. SEcTION A.—ALFALFA SAMPLES COLLECTED aT CHiIco, CaLt.—Continued. Weight. Moisture. Sample and stage of id Saal ae Erowth- Gran inter, Air | Oven Original Air-dry Lost in air times dry dry. material. material. drying. One-tenth bloom: Ounces. keeclouee Ounces.| Per ING S5Sieen 2 at sea See 123.2} 30.95} 30.95 26.0} 78.9 ING Sons Sean sn es ao ee 123.2.) 32:20) 31-95 28.5] 76.9 ING DSS ees tse ee 123.2} 30.95] 30.95 2hoa|) adda INOP S42 oa ssc 2 eee eee 123.2} 34.7 34. 20 31.0] 74.8 ING 585 at ce a ee $23.2 |. 31.95 | (Siz 282 Olas AV CFALO 55.5 caciteie ooe ece a eee fice se ee GW7.1 Full bloom: NOr5162 soe (PAPA Sith) Bue Stes (424 INOI5 Mes. hos sae 123.2} 35.45] 35.45 31.5} 74.4 INOS D1Ste. eee SALE Ts 123.2] 35.20) 34.95 31.0| 74.8 INO 5710! oo ie ee ee 123.2) | «3457 34.95 31.0] 74.8 INO 5S0S Pats ee 123.2 | 35,45 | 35.20 31.0] 74.8 INVETALO sso 4-5 - Gea smectic cs |e Sse sc ee] 2 acece c|eaees cee 74.6 Past full bloom: INOS (lesen ee eee 123.2} 38.20} 37.95 33.5] 72.8 : 69.2 INGSDI2: eee 123.2 | 37.45] 36.95 S300) = fase 10.6 70.0 INOS Dio see hae ener eee 123.2} 35.95] 35.70 31.5} 74.5 11.8 71.0 INOfST4- Eee ee 123.2} 36.70) 36.70 32:5). 73. % 11.5 70.2 INOS O( anes ae eee eee 123.2 | 37.95 | 37.70 33.5 | 72.9 aie, 69.5 Average.....--- SUVE Si eseb ee eEeES Paes = bow 73.44 .188| 11.44 .131] 70.04 .188 SECTION B.—SORGHUM SAMPLES COLLECTED AT AMARILLO, ‘TEX. [Dates of weighing: Original material, Aug. 17; intermediate, Nov. 2; air-dry material, Dec. 17.] No oii ener eee | 135 25 15.5 13.0} 90.4 16.1 88.5 Now Gennes eae | 136 30 15.0 11.5] 91.5 23.3 89.0 No es > ae ee | 134 25 15.0 13.0] 90.3 13.3 88.8 No 24421. 426 22h dee 138 23 15.0 13.0} 90.6 13.3 89.1 INGioi5 28 er ee Te | 135 24 15.0 13.0] 90.4 13.3 88.9 AWerages = tn ene [EEE CLOT lo Teee ae oe Ae ae | 90.640. 134 | 15.941.169 | 88.940.063 Heads in boot: | NO! 2462. dejan tes = 139 40 7.0 19.0| 86.3 INO: 247-20 Sipe ae 138 39 24.0 18.0} 87.0 NO G248s.8 eck. see ee | 138 36 | 22.0 17.0) Syor NGC Dae Bek et ee 140 39 25.0 18.0] 87.1 INOS 250 os Bene eae ee | 140 38 24.0 17.5 | 87.5 ANCIAL O =o. o2)in mw piscise oe | Scoscies|sooscee =| ba ceesee loseeete 87.1+ .146 Beginning to head: | INO od ha ee ae 135 40 28.0 20.0 | 85.2 28.6 79.3 ING 52 3 aa 113 42 29.0 21.5] 84.0 25.9 78.4 ING 25O oa ee 134 39 27.0 21.0| 84.9 22.2 80.6 INGSosiks Scere 389 41 29.0 21.0| 84.8 27.6 79.0 IND aed ae 140 40 28.0 21.0 | 85.0 25.0 80.0 I. TI YS el (5 RR UE a es = 8 | RST 84.84 -124 | 25.94 .670| 79.54 .232 Heads in bloom: | IE a fe ipa aaa 138 48 34.5 26.0} 81.2 24.6 75.0 i oy AL Cte terete SBS 138 48 35.0 26.0 | 81.2 25.7 74.6 ING HOSS Fe SAS HE 138 49 35.5 28.0| 79.7 21.1 74.3 ING2250 fe. eer ie 139 47 34.5 27.5 | 80.2 | 20.3 75.2 ING 260S er ee ee see 138 47 35.5 28.0 | 79.7 | 2d 74.3 AVOTAPO 255 eee eel sc ton oe] eee eee 80.44 .204 22.64 .652 |) 74.74 .111 Ripe Nasal se. 2c) 2 ee 132 58 43.5 34.0| 74.3 21.8 67.0 ING ee ats eee eee 136 59 45.5 33.0| 75.7 27.5 66.5 Nowa ete Be 135 59 44.0 33.0 | 75.6 25.0 67.4 IN Geeta tise Nes othe 135 58 42.5 33.0 | 75.6 22. 4 68.5 Noor. os are oe 141 62 46.0 35.0 | 75.2 23.9 67.4 RSVGragece. Moa sfotekioe. «[aserintes 84.5 + .185 | 15.38 + .572 | 81.6 + .192 Soft dough: RS Ty ya o. 311 38.25 | 28.75] 24.75 | 83.5 13.8 80.9 No. 312... 37.00 | 31.50] 26.50 | 81.4 16.0 77.6 No. 313... 37.50 | 34.50] 29.25 | 81.4 15.1 78.1 No. 314 39.75 | 35.75 | 30.00 | 80.2 16.0 76.4 No. 315 45.75 | 40.25 | 33.50 | 79.2 16.7 75.0 PAV CTARO tas case cet sees eee ceed eee eo aeafiodeesd. |. See ee 81.1 + .434 | 15.5 + .302 | 77.6 + .593 Hard dough: Spies 2 oe eesee eae RS) INOW SIG seer osccenccctccs 159.75 | 46.75 | 41.25] 34.00 | 78.7 AES 74,2 INOS STEERS E esas oss 166.75 | 57.75 | 38.25 | 32.75 | 81.4 14,4 77.1 INQSISE ss ccacccesteaenc: 131.75 | 42.75 | 40.25 | 33.50 | 74.6 16.7 69.4 INO3519 ss fo ssc een ews 149.75 | 46.75 | 48.75 | 36.50 | 75.6 16.5 70.8 INGn S20 ese wcne sate caciecste 160.50 | 49.50] 45.50] 38.50 | 76.0 15.4 71.6 INVOLAUO wena caceocseex ain sl sess sccasec|eccsees<]-aeeacins 77.3 + .746 | 16.1 + .326 | 72.6 + .823 Seed ripe: Pia Cie | a IN@HSALoel a. ete ote 151.00 | 54.00 | 42.2 36.75 | 75.7 13.0 72.1 NOUS 22F eee esets sesiee ots 149.25 | 53.25 | 41.75 | 34.75 | 76.7 16.8 72.0 INOS O2a senses coccee ec 139.25 | 50.25 | 48.75] 39.75 | 71.5 18.5 65. 0 INOS S24 ace cise sacs 157.00 | 61.00] 56.5 47.75 | 69.6 1555 64.0 INOS 3202s miek Sone as oeee 141.50 | 49.50 | 46.5 38.75 | 72 6 16.7 67.1 PACE REO apse essere ia cicia cinioeic wcia scisis cilaicte cence | omeeicisins 73.2 + .795 | 16.1 + .549 | 68.0 +1.033 SECTION D.—TimmoTHY SAMPLES COLLECTED AT NEw LONDON, OHIO. [Dates of weighing: Original material, May 20 to July 20; intermediate, Sept. 2; air-dry material, Sept. 28.) Very young, May 20, 10-12 inches high: ING: 449 Soe oot Se B24 eee ee 31 28.0 | 77.5 9.6 75.0 Just heading: i ee ea INO S4D0 Mas soon cece cee soe 138 37 35 32.5 | 76.5 ia: 74.6 INO ADL ako ocan one n ae os 158 42 41 37.0 | 76.6 9.7 74.0 JST He CRS SEE eCE ROO 4 B5S5O00R DOC BASS BOGbcoas EHoaBose 76.6 +0.034 | 8.4 40.620 | 74.3 +0. 143 Eee pico, June 20° | fee ie ee 137 A 43 39.0 | 71.6 9.3 68. 6 No. BOS ce SOS e aes cine cals 135 43 42 39.0 | 71.2 dak 68. 9 ACTA LO sotca sacccccces|s Saocacd ceccesd ecanaodod Kesessce 71.4 + .095| 8.2 + .525 | 68.8 + .076 putt bloom; June 26; [ae ae be aan aes eae Be eee tie note alee wie 131 47 46 42.0 | 68.0 8.7 64.9 No. 455 Eaten woecne sce 132 51 49 44.5 | 66.3 9.1 62.9 FAN CERUO Seren Stine Baclnc|siccicebicclsooodsiwmclocesccea|seceness 67.2 + .406 | 8.9 + .095 | 63.9 + .337 Reaves drying, July 7: i = San Tes aan ep Ee ee 119 56 54 48.5 | 59.3 10.1 54.5 No. 487 So ee ee 127 62 60 53.5 | 57.9 10.8 52.8 4 SIGGTNT RaSR eS ea CeABCel BESCREEE Seae scéd be Suodaals eeteoe 58.6 + .334 | 10.5 + .169 | 53.7 + . 406 Reed anere, July 20: FS Ppa] Peete tie ap ae Seine clei 2 131 75 70 64.0 | 51.2 8.5 46.6 No 2 ae eee 131 74 71 64.0 | 51.2 9.8 45.8 ASTGRIEO oh GE A SEE eS aes [oats (Pateeetemine] [ion nee 51.2 + .000] 9.2 + .311 | 46.2 4+ .191 26 BULLETIN 353, U. S. DEPARTMENT OF AGRICULTURE. These results, which agree fairly well with the averages for timothy and alfalfa cited on page 23, show a decided decrease in moisture per- centage as the crop approaches maturity. This difference is least in alfalfa and greatest in timothy, although in sorghum it was also con- siderable. The exact relation of the three crops as regards the moisture content at different periods of their growth is not apparent, because the stage of maturity when samples were taken was not identical in the three crops. It is quite probable that the mature seed stage of timothy, when the moisture content reached the very lowest figure, 51.2 per cent, was relatively later in the life period of the crop than was the ripe stage in the sorghums. This may account partly for the rather decided difference in the amount of moisture contained by the two crops at this stage. It appears, however, that sorghum has an unusually high moisture content throughout its entire life period. The fact that the very young sorghum plant is approxi- mately 90 per cent water, while the young timothy is only 77 per cent and the young alfalfa 79 per cent water, suggests one reason why cutting sorghum when it is very immature affects the feeding value of the resulting hay so much more seriously than a like treatment does timothy or alfalfa. These results are more apparent in the summary (Table VII), where the averages are brought together so as to make comparisons easier. TaBLeE VII.—Summary of numa percentages of moisture in sorghum, timothy, and alfalfa at different stages of growth. Moisture. Place, crop, and stage of growth. Original Air-dry Lost in air material. material. drying. Amarillo, Tex., Red Amber sorghum: Per cent. Per cent. Per cent. VICES YOUNG: 2 Saas jan ceeccin chee eee ek one eee eeeoer 90.640.1384] 15.9+1.169 88. 9+0. 063 Shooting for h eads* sina aes Noe enema 87.14 .146| 26.54 .725 82.54 .347 iBerinning, to head's=ss- esos seen cae eee eee ee ..-| 84.84 .124] 25.94 .670 79.5% .232 UIE DOOM wine Bee sec Ce ae ee ae eee 80.4+ .204] 22.64 .652 74.74 .111 12 OY STi OER EERE Se a ae ee Pao LR ae! SS Ok aa ae 75.34 .157| 24.14 .612 67.44 .199 Hays, Kans., Red Amber sorghum: Very young . Sieleaiewiniels seo me rEE cis ae Nation = See eee mrsinert 89.24 .344] 15.44 .349 87.0-+ .270 OOM S as Se laen a aisinis awe os ooie nal = eee eee Saree 84.54 .185| 15.34 .572 81.64 .192 Softidougneecrs. sos oc chiens Scere oe bee es ee eee 81.1+ .484] 15.54 .302 77.64 .593 HMardidoughis 2 oe eee ke SS. 5. A ee ee 77.34 .746] 16.14 .326 72.64 .823 TRU shee eas aioe wrerseysiee ote wis nse is Sa ae Re Res Sree oar 73.2+ .795} 16.14 .549 68.0+1. 033 New pondoU, Ohio, timothy: ! Maye 202 Bee dais closten bal wiae Seite OS 2. ot ee epee stemieneie me ee 9.6 75.0 Very ee PAIN CHES hi Sh VUNO Geen 2 5 Hee eee 76.64 .034 8.4+ .620 74.3+ .14 Barlysploom:; June) 20 sere ae tee cto eee eee aoe ee 71.4+ .095 8.24 .525 68.8+ .076 Mull bloom une; 26s .ce =o ee sone ts ee eee eee 67.2+ .406 8.9+ .095 63.9+ .337 Leaves drying, a DUA Ae sOO ciate ARENA hs GABE SRT 58.6+ .334} 10.54 .165 53.74 .406 Seedsmature, Sully 20m eer ee oe care ors hoes eee een cee 51.2+ .000 9.24 .311 46.24 .191 Chico, Cal., alfalfa: Plants 12 inches lott DS OSS ha a i Ree SO eau see 78.94 .412} 12.54 .314 75.84 .395 First bloom to one-tenth in bloom.....................--- 77.14 .393} 11.74 .689 74.14 .289 ull blooms 3235). Bae eee aos dine inan eek Reece aces 74.64 .060] 11.24 .124 71.54 .045 Pastifull bloom s..\. ce steeteesiees os ookce sen eee cio aces 73.4+ .188] 11.44 .181 70.0+ .188 1 Only 1 sample taken on May 20; on other dates 2 samples were taken. MOISTURE CONTENT AND SHRINKAGE OF FORAGE. 27 The effect of the stage of development on the amount of moisture remaining in the air-dry material, as shown in Table VII, is also a matter of interest. In the case of alfalfa at Chico, Cal., the young plants air dry contained a little more moisture than the older plants. At New London, Ohio, timothy showed practically no difference. Red Amber sorghum at Hays, Kans., showed no difference, while at Amarillo, Tex., the young plants contained decidedly less. The uniformity of the moisture content at Hays and the lack of uniformity at Amarillo (Table VI) is accounted for by the fact that at Hays the stems of each sample were split, thus allowing the complete drying of the mature samples, while at Amarillo the stems were not split, and the immature specimens dried out more completely than the mature ones. LOSS OF MOISTURE IN FORAGE DURING THE EARLY STAGES OF CURING. To determine the rate ot loss of moisture in different crops during the period directly following the cutting in different localities and under different weather conditions, the following crops were used: At Arlington Farm, Va., alfalfa and a mixture of tall oat-grass and orchard erass; at Chico, Cal., alfalfa; at New London, Ohio, timothy; and at Hays, Kans., sorghum. The material was cut as quickly as possible and weighed immediately, using about 100 pounds green weight. This 100 pounds of green forage was placed on a canvas and weighed every 10 minutes through 1 hour, and every 30 minutes thereafter until 4 hours had elapsed. At Hays and New London determinations were made under both clear and partly cloudy con- ditions, but at Chico and Arlington Farm determinations were made for each crop under one condition only. At Hays, Kans., the experiment was carried out with Red Amber sorghum in the soft-dough stage, and records of moisture loss were secured both for forage scattered as it would be in the swath, and also bunched, as it would be if raked into windrows. On August 18 the sky was partly cloudy, the wind was blowing but little, and the maximum temperature was 104° F. On September 25 the first weights were taken at 1.40 p. m., and the last at 5.40 p.m. The day was bright, with a gentle breeze and a maximum temperature of 82° F. Table VIII gives the rate of loss of moisture in these experiments. The rate of loss was greatest in the scattered material, but the difference is not as great as one might expect. In the first 30 minutes the loss ranged from 1 to 2 per cent. The difference in the amount of moisture lost by the bunched and the scattered lots was 4.89 per cent on August 18 and 4 per cent on September 25. The greatest loss in 4 hours in the bunched lots was 8.2 per cent and in the scat- tered lots 13.1 per cent. 28 BULLETIN 353, U. S. DEPARTMENT OF AGRICULTURE. TaBLeE VIII.—Rate of loss of moisture in Red Amber sorghum during the early stages of curing at Hays, Kans., in 1914. On August 18. On September 25. Time of Time Bunched. Seattered. Bunched. Scattered. weighing. |elapsed. Weight. | L0ssin | weignt, | Loss in | weignt. | Lessin | weignt. | Lossin weight. weight. weight. weight. Hr. m.| Pounds. | Per cent.| Pounds. | Per cent.| Pounds. | Per cent.| Pounds. | Per cent. AAD ye Tens evel yee emcees 110.0 0 99.5 100.0 0 100.0 ILS HTSUS Sales, LW 109.5 sik 99.0 5 99.5 25 100.0 0 20S pales cele 20 109.0 9 98.0 1.5 99.0 1.0 99.5 0 PART O18 Sonos ol) 108. 0 1.8 97.5 2.0 98.5 1.5 99.0 1.0 PPS UN sooolese. oD) 107.5 2.3 97.0 2.5 98.5 15 98.0 2.0 ARs i sssaicon Fl) 106.5 3.2 95.5 4.0 96.0 4.0 97.5 2.5 PAS TRIS e aed bos 106.0 3.6 94.5 5.0 97.5 255 . 97.0 3.0 SATs ool Ly SW 104.5 5.0 93.5 6.0 97.0 3.0 96.0 4.0 3249 Dede. = 104.0 5.5 90.5 9.0 96.5 3.5 95.0 5.0 CF ay ore 1 « ees eae 0) 103.0 6.4 89.0 10.6 96.5 3.5 94.0 6.0 4545) meee | ome 102.5 6.8 88.0 11.6 95.5 4.5 93.0 7.0 Held Pedeeeel aso 102.0 7.3 87.0 12.6 95.5 4.5 92.0 8.0 BAS Domes ele 4 vec ce 101.0 8.2 86.5 13.1 95.0 5.0 91.0 9.0 The striking point to be noted in connection with Table VIII is the great difference in the rate of moisture loss between sorghum and alfalfa or timothy, as indicated in Tables VIII to XI, inclusive. At New London, Ohio, determinations were made of the rate of loss of moisture in timothy cut when in full bloom on July 4 and again on July 6. Thesky was partly cloudy on July 4 and the temperature was 76° F. at noon. On July 6 the sky was clear and the thermome- ter registered 80° F. at 11 o’clock a. m., 79° at 1 o’clock p. m., and 76° at 4 o’clock p.m. In each case the samples were scattered in drying. TABLE IX.—Rate of loss of moisture in timothy during the early stages of curing at New London, Ohio, in 1914. Time of weighing. ae. Weight. Loss in || Time of weighing. one Weight. es elapse weight. elapsed. weight. July 4: Hr. m. | Pounds. | Per cent. || July 6: Hr. m. | Pounds. | Per cent. TOO MES ese eee 115 0 UNAUUES enae shee AS ieee 115 0 2 ON aM tere <= 551) 112 2.6 HPO ae meee elo 112 2.6 2 S20 Dean ee Sonal) 110 4.3 P20 ASM ere BSA 24) 110 4.3 12230 Pome a. ee -- 30 107 7.0 L130 ahme os oes sa ro) 108 6.1 L240 pemMssae- == -- 40 106 7.8 11.40 a.m...... -- 40 106 7.8 TUS UTS Mac Shae- sey POO 105 8.7 ASO AS MNS secre se 50 104 9.6 LOOM ames ae 1 103 10.4 IPA Meas Soa aee Law 103 10.4 1:30 Damas ot 1 30 99 13.9 12:30). 2-5 4. 1 30 98 14.8 BlOOpamee. Doe 96 16.5 TOO prmicees. ae 94 18.3 2:30: Dome ances 2 30 92 20.0 1:30 pemees cee 2 30 89 22.6 S00) pepiteee ee Sige 88 23.5 2.00 pumice see Seae 86 25. 2 3.30 pame- 222: 3 30 85 26.1 2.30 pease asics 3 30 84 27.9 4:00\pS Mise se a 7 ee 83 27.9 3.00 DeImMeeases ye 81 29.6 4-30 pe Mss. 5522 4 30 80 30. 4 Ste a itsle ao 550 4 30 7 32.2 S:00' poms. t OeRSS 80 30. 4 200 p.Wh: oo 0.6 Dae 77 33.0 The data given in Table IX show that in the first 30 minutes after cutting on July 4 there was a loss of 7 per cent and on July 6 m the same time a loss of 6.1 per cent. In the first hour on both dates the loss was 10.4 per cent, and in 5 hours the loss was 30.4 per cent on MOISTURE CONTENT AND SHRINKAGE OF FORAGE. 29 July 4 and 33 per cent on July 6. These results show the rate of moisture loss in timothy at New London, Ohio, to be very nearly the same as that of alfalfa and the mixture of tall oat-grass and orchard grass at Arlington Farm, Va. (Table X), where the atmospheric humid- ity and the temperatures are very similar to those at New London. Determinations of the rate of loss of moisture in amixture of tall oat- grass and orchard grass and in alfalfa during the early stages of curing were made at Arlington Farm, Va., on June 3 and on October 16, 1914, respectively. The data secured in this work are given in Table X. TABLE X.—Raite of loss of moisture in a mixture of tall oat-grass and orchard grass and in alfalfa during the early stages of curing at Arlington Farm, Va., in 1914. Tall oat-grass and orchard grass. Alfalfa. s Pei im Fs Loss i 3 see im 5 Ie Time of weighing. Sea. Weight. arash: Time of weighing. ane aL Weight. TOKE. June 3: Hr. m. | Pounds, | Per cent. || Oct. 16: Hr. m. | Pounds. | Per cent. 12°30) ps Mes. = Se 100. 0 0 12.40 p. m...... Cee yi 100.0 0 12:45 p. M.-.-.-. 15 96.5 oD PAS OS OS sR aae 10 98.0 250 1 P4335) FONE Sea eee 25 95.0 5.0 100 pemes eee. 20 96.0 4.0 IL) Ds itleaAoake 40 92.5 7.5 A ios lesae ae 30 94.0 6.0 20) s ses 50 90.0 10.0 E20 sp HIE ee 40 91.0 9.0 1S0i pam ee lars 88.5 11.5 JES ORO ee ae 50 89.0 11.0 11 25] Os ee oe etd 86.0 14.0 140) Fe = ee 86. 0 14.0 PONT Tit aoa se 1 45 80.5 19.5 ZO We Mies ee 1> 30 81.0 19.0 24D Wes. aos 2A5 76. 5 23.5 2.40 p. M...-.- Ie Pe CW) 23.0 ays) TOs lee oe 5 2245 73.0 27.0 3520) Deeks eee 2 40 75.0 25.0 340)Ds We 225. Sheal'5 70.0 30.0 3405s Ws sae By: bse (PS 27.5 2. Vs) ptt eae 3 45 66.5 33.5 410 pam: tea-- 3 30 69.5 30. 5 4,40p.m...... 4G 68. 0 32.0 The afternoon of June 3 was bright and fairly free from cloudiness, with a maximum temperature of 82° F. Under these conditions the mixture of tall oat-grass and orchard grass which was scattered on a tarpaulin lost 5 per cent of its weight in the first 25 minutes, 11.5 per cent in 1 hour, and 33.5 per cent in 3 hours and 45 minutes after cutting. The weights were taken as quickly as possible and the material scattered each time as soon as the tarpaulin was lowered. It will be noted that the loss of moisture was quite rapid, exceeding shghtly that of the timothy at New London, Ohio. The afternoon of October 16 was partly cloudy, but very warm for that season, the maximum temperature for the day being 73° F. Alfalfa under these conditions lost 6 per cent of its weight in the first 30 minutes, 14 per cent in 1 hour, and 32 per cent in 4 hours after cutting. On a bright day and with the same temperature as that prevailing on June 3 it is probable that the loss of moisture would have exceeded that of the mixture of tall oat-grass and orchard grass. Determinations of the rate of moisture loss in alfalfa at Chico, Cal., have been made during several years, and these results are given in Table XI. These data appeared in slightly different form in an earlier 30 BULLETIN 353, U. S. DEPARTMENT OF AGRICULTURE. publication by McKee,! who called attention at that time to the fact that because some varieties of alfalfa after cutting lose moisture more rapidly than others the field weights will be incomparable unless sufficient time has elapsed to insure a uniform moisture content. Taste XI.—Rate of loss of moisture in alfalfa varieties during the early stages of curing, at Chico, Cal., in 1910, 1911, and 1912. Time elapsed. Arabian. Peruvian. Ordinary. Weight Weight. Time of weighing. & Lossin 3 - |Lossin x Lossin a: é 2 q E weight. a : weight. Weight. weight a) 3S eS |lrtey {BAe s 5 g 5 A aa = io) Ay ie) nS Test A: Per ct. Per ct. | Grams.| Per ct. June 22-3191 Oe teases ster | osrec eaters 254. Oil Peeeeee 0 216: Osean ee 0 240.0 0 ToT) PRY MONO = Se Sal bose 24) eee 98 Salons eee. ae abel pete) Rages 58.0] 107.5 55. 2 June 25 O1O Mees leeece 7 PAal aaees ThOSy hed Seeciee 69.8 | 91.6 ].....-. 66.8 83.3 65.3 Test B:1 June 9, 1911 2— OL22 ia trrs Saie rae | agen ce | part a 0050) |B2=aeee 0 A000 2eeeeee 0 400. 0 0 IDES AGM ee eS olisanes Gls One 243= Onl eeeee aoa OAS eS oas5e 32.2} 269.3 32.7 LED DDN eee ale ae ee 3 IC Rae eee coe 5654s ete alee 46.9] 205.8 48.6 Aspe ees od ee | ee Ble Bis PIG coous Te PSO ce ooe 56.8 175.9 56.0 Septe2 (onl eee eee TOU Saaeelaeeee S8h6" Sees 79.1 SaHe) | Eooneos 79.2 82.5 79.4 Test C: June 9, 1911— OO Way as NE ea ee ea ae ed 2 100 (Uae aoe ae 00 (tee fee eee ee Se 1 BOE 01 eee. st eee Tlie GE YS: 2 ree 73 ZisOisaeecee 78 22. Once cette a eee 2M Ee asecsce| sss A OSM ER eS 41 595.0: |Reeeee 48 52:10) |seeeweda cemeene 0 Tie ee Sg Gi ilosa| ase 36 6420 Bess 42 58:0) |. cee a eee June 129191. ese 34: ESSE enon lasceaee 24 (CONOR Ree 1650: asec eee Aug 8) 19M eso GO! See S| ae Re 2 22 (BONE ae 22 183.0). se ccee ee Bees ees Test D: June 4, 1912— Oras bee ere ee Sa eee | eee esd 100 Oa Saas ee 100 OF. RoR a ee TU ers rien Ve ee ee ate | ee 1 Ds ee eS 78.5 7G) Oar 83.5 16 ee eee TAS 0 Old ee, Sia oe aN Neer | get eae 60.5 BOr lect 65.5 34250 esse ee epee PAN OS 8 Vesey iene ey Sia Lesa A ee yet ra esse 34.5 5) BS SEGSS 31.5 G855 0S Se eee Apri eee ==>: GU SUES ac ey 26 TERN Berges c OA) 55 007575) cee See ogee 1 The weights oftest B arean average of two samples in each case. Theleaves constituted 56.4 percent of the weight in the Arabian variety, 52.5 per cent in the Peruvian, and 49.8 per cent in the ordinary. 2 First weight was taken about five minutes after cutting. These data indicate very clearly that the rate of loss during the first four or five hours at Chico, Cal., greatly exceeds the loss during a like period at Arlington Farm, Va. This is doubtless due to both the higher temperature and the lower humidity of the atmosphere at Chico, the loss during the first 14 hours at Chico being nearly equal to that during the first 3 hours at Arlington Farm. In connection with these results it is well to note that the weighings of alfalfa at Chico were made in the month of June, while those at Arlington Farm were made in October. It is also interesting to note that in tests B and C the Arabian variety lost moisture faster for the first few hours after cutting than the Peruvian or the ordinary alfalfa, but that in the end it had prac- tically the same percentage of dry matter. A high percentage of leaves is usually thought to indicate a high moisture content, but the Arabian has 6.6 per cent more leaves than the ordinary, and yet the total moisture content is about the same for the two varieties. 1 McKee, Roland. Arabian alfalfa, In U.S. Dept. Agr., Bur. Plant Indus. Cir. 119, p. 25-30, 1913, MOISTURE CONTENT AND SHRINKAGE OF FORAGE. 31 VARIATION IN THE MOISTURE CONTENT OF GROWING ALFALFA DURING A SINGLE DAY. In order to determine whether a different percentage of moisture is to be expected in forage plants cut at different times of the day, five samples of alfalfa were cut at 8 o’clock in the forenoon and six samples at 3 o’clock in the afternoon. The alfalfa was in a fairly vigorous condition and about one-tenth in bloom. The day was warm and sunny. A detailed statement of the results with each sample is given in Table XII. Taste XII.— Moisture content of growing alfalfa at 8 a. m. and at 3 p. m., at Chico, Cal., in 1914. Weight. Moisture. ee G Air dr O Original Air-dry | Lost in ai Treen, ir Y> ven rigina -ary OSt 1n alr June 13. June 30. July 27. | dry. material. material. drying. Cut at 8a. m.: Ounces. | Ounces. | Ounces. | Ounces. Per cent. Per cent. Pef cenit. INOS 5495 fo oases 123.2 33. 70 31.95 8.5 | 76.9 10.7 74.1 INOS 550 ee ee ee 123.2 35.95 33.70 29.0 | 76.5 13.8 C745 7i INGY SSA coe 123.2 35.70 32. 45 29.5 | 76.1 9.1 TBC! INOM55 22 ce acon eens 12552; 34.95 35. 20 Sa 450 10.5 71.4 INQ'boSisc sels aoe was = IDAK- 34. 95 34.95 31.5 | 74.5 9.7 71.6 MIGRATE Sco SSeSUCOs se Bode ated Bae Geen Ss ES enaean mea saaceas 75.740. 216 | 10.8+0.346 | 72.740. 231 Cut at 3 p. m.: OF OOaP eee es cece 91.2 26.95 26. 95 24.0 | 73.6 10.8 70.4 INOS55 See ceowc see 91,2 26. 45 25.70 VARS |) TRB IPA Y 71.8 INOw5b6 sect eee sees 91.2 24.70 23.95 ZAUOUTCeO R2S2 73.7 INOS 557 sacs en see cee 91.2 26. 20 25.70 222 OWN One 12.3 71.8 INO} 5nO ee cece 91.2 27.45 27.70 PERT Uta | eS 69.6 INOS O00 na setae ee 91.2 26. 70 26.95 24.0 | 73.6 10.8 70.4 Meanie mepeme tir 2 ale ets lead ae. 74.74 .263 | 11.64 .127 | 71.84 .261 The mean for the two methods of treatment shows 1 per cent more moisture in the alfalfa at 8 a. m. than at 3 p.m. While this differ- ence is not large, there is a sufficient number of samples so that the results are dependable. In actual practice this result has little sig- nificance, but it is of interest to find that in the open field under favorable moisture conditions transpiration may exceed the absorp- tion of water by the roots sufficiently so that the moisture equilibrium in the plant tissues is not maintained. MOISTURE CONTENT OF BALED HAY. In order to give some idea of the amount of moisture in ordinary baled hay, samples were taken from oat hay in the bale at Chico, Cal., at two dates, the first about one month and the second about two months after the hay was baled. Ordinary commercial hay was used in this experiment, so the moisture percentage may be con- sidered as fairly representative of that in the grain hays on the market in California. The moisture content, as determined by two sets of samples, is given in Table XIII. 32 BULLETIN 353, U. S. DEPARTMENT OF AGRICULTURE. TaBLE XIII.— Moisture conteni of baled oat hay and moisture lost in air drying at Chico, Cal., in 1914. Weight. Moisture. Sample. Orig- P July | July | July | July | Aug. | Aug. | Aug. | Oven | inal mae 1. 10. 20. 27: 4, 19. 24. dry. sam- | grvi ple ying: Ounces. |Ounces. |Ounces. | Ounces. |Ounces.|Ounces.|Ounces.|Ounces.| Per ct. | Per ct INORG lee ee ee AA 5345200) |443525.1) GAZ aiO eee eal eee ae eee eee 39.0 12.4 4.0 INON5O2 eee eee 44.5 | 43.00} 438.25 Z SITS 0 We cee | ee |S ne 39.0 12.4 4.5 INOS O63 See ae eae ees 7 Ws Beta ye| bases: Day da yol teste: 30 Oat ge: 2G Wa Sone 39.0 12.4 4.5 INOS GAS eee oe ae 44.5 43.25 43.50 ZH oc] Deere eseree 39.5 11.3 3.2 INO: DOS soos So ee 44 eH AQ SOM weight approximately 6 per cent. The shrinkage in loose timothy hay and the variation in its weight because of changes in atmospheric humidity are shown in Table XV. The hay used in both lots 1 and 2 was practically pure timothy which was cut July 10. The hay in lot 1 was allowed to cure in the field and the 108.5 pounds were taken from the windrow July 11, when it appeared to be in about the right condition for placing in the mow. The hay in lot 2 was taken immediately after cutting and weighed, while green, 512 pounds. After weighing, it was spread out on a canvas and allowed to cure until the following day, being turned or stirred several times to hasten the drying process. On July 11 it was placed in burlap sacks and removed to a barn, where it was kept under the same conditions as lot 1. The first weighing of lot 2 was made on July 17, and even at this date it was evidently not so dry as lot 1 had been on July 11, although both lots appeared 1Jordan, W. H. Experiments and investigations conducted at the Pennsylvania State College, 1881-2, p. 7-14. Harrisburg, Pa. MOISTURE CONTENT AND SHRINKAGE OF FORAGE. 85 dry enough on that date to place in a mow. The weight of the hay at this stage, when it was supposedly ready to be placed in a barn, is used as the base for figuring all percentages. TaBLE XV.—Shrinkage of timothy hay after storing and variation in weight due to changes in atmospheric humidity, New London, Ohio, 1914. Lot 1. Lot 2. Date of Percent Percent Weather conditi weighing. ercent- ; ercent- j eather conditions. Weight age of Loss in Weight age of Loss in * | original | weight. * | original | weight. weight. weight. 4 Pounds Per cent.| Pounds. Per cent YORK WO asa le eae aed ees sense Bemeame rm OSE UE SEO ene ose | ae ee a, lear. fulysie a 108. 5 100. 0 (1) saa] aspera tay a wake el ea ae Do. Salva 103.5 95.4 4.6 295. 25 100. 0 0 Do. INES PW 5 S502 97.5 89.9 10.1 246. 00 83. 4 16.6 | Rain, Aug. 6. Shyer ns 101.0 93.1 6.9 250. 00 84.7 15.3 | Rain. Sept. 11... 99.5 91.7 8.3 250. 75 85. 0 15.0 Sept. 21... .. 97.5 89.9 10.1 242. 25 82.1 17.9 | Very dry. Sept. 28:.... 97.5 89.9 10.1 244.75 83.0 17.0 | Clear. Octzo eee 96.5 88.9 ible al 243. 75 82.6 17.4 | Cloudy. Octoisen-e- 99.0 91.2 8.8 251. 75 85.3 14.7 | Rain on several preceding ays. Oct: 198s. 21 100. 5 92.6 7.4 255. 50 86.6 13.4 | Cloudy and some rain on every day since Oct. 13. Octs26302) |S Se SES earns | Eee ereene 253. 00 85.8 14,2 | Clear from Oct. 20 to 23; Oct. 24, rain; Oct. 25, clear; Oct. 26, rain. INCOM Aree eens cee fee [ea eye Tee 250. 75 85.0 15.0 | Weather clear nearly all the time since Oct. 26. WIGS Lobes ESS ae Bose BOSE Sea oe e Seceaeeee 247. 75 84.0 16.0 | Weather clear since Nov. 2. TD EOS PAS Steel [era bee Min Se ese begun 252. 00 85. 4 14.6 | Cloudy for four or five days preceding Dec. 2. Rain on two days. The seasonal effect is not so marked in this instance as it was in the alfalfa at Chico, Cal., but the more frequent weighings provide an opportunity to observe the almost immediate response of loose hay to changes in atmospheric humidity. This point is illustrated best by the increase in weight during the period from October 13 to October 26, a maximum increase of 4 per cent over the weight reg- istered on October 5 being noted on October 19. This decided increase in weight is accounted for by a period of almost continuous rain between these dates. Clear, sunny weather after October 26 caused sufficient loss of moisture to reduce the weight 2.6 per cent by November 11, showing that even as late as this in the season dry, sunny weather would affect the moisture content noticeably. The average amount of shrinkage from a field-cured condition in lot 1 was 8.6 per cent, while in lot 2 the shrinkage was 15.6 per cent. A compilation ! of the results obtained at several experiment stations showed an average shrinkage of 17.9 per cent in timothy when it was stored in a barn from 5 to 10 months. These figures represent fairly well the shrinkage that is to be expected in timothy hay which has been stored in a haymow, but more data on this point are needed. 1Vinall, H.N.,and McKee, Roland. A digest ofliterature relating to the moisture content and shrink- age of forage. In Jour. Amer. Soc. Agron., v. 8, no. 2, 1916. 36 BULLETIN 353, U. S. DEPARTMENT OF AGRICULTURE. SUMMARY. The variation in moisture content in field-cured forage often gives rise to errors greater in amount than the differences in yield between improved varieties or different methods of culture. A study of the use of samples in correcting forage yields indicates the following results: (1) Air-dried samples are a little less accurate than oven-dried samples, but the difference is so small that the air drying of samples can be relied upon for all prac- tical purposes in correcting forage yields. (2) Much greater extremes are found in the samples of field-cured material than in the samples of green material, indicating that replication of samples is more important in the former than in the latter. (3) Corrections by means of samples can be accurately made from either green or field-cured material, provided care is used in sampling. (4) Considering accuracy of results, facility of handling, and ease in figuring per- centages, 5-pound samples of field-cured material and 10-pound samples of green material are recommended as the most desirable sizes for practical use. (5) Samples need not be replicated more than three times. (6) The percentage of moisture in the different crops at that period of growth when they are ordinarily harvested for forage was as follows: Alfalfa at Chico, Cal., 75 to 78 per cent; average, 76.9 percent. Alfalfa at Arlington Farm, Va., 74 to 76.5 per cent; average, 75.2 percent. ‘Tall oat-grass and orchard-grass mixture at Arlington Farm, Va., 71 to 73 per cent; average, 72 per cent. Timothy at New London, Ohio, when in full bloom, average, 67.2 per cent. Sorghum at Amarillo, Tex., 70 to 73 per cent; average, 71.2 per cent. These percentages are probably near the average for each crop, but the fact that McKee found 85.8 per cent and Farrell an estimated 79.5 per cent of moisture in alfalfa indicates that it will be impossible to establish any arbitrary percentage of moisture in the green plant as a basis for correcting forage yields. (7) The average amount of moisture in field-cured material was as follows: Alfalfa, 22.3 per cent; timothy, 20.3 per cent; tall oat-grass and orchard-grass mixture, 29 per cent; sorghum, 43.2 per cent. The moisture content of field-cured material varies so widely that it can not be foretold with accuracy. The use of the sample method in correcting forage yields would sreatly assist in standardizing agronomic data and do much to promote greater accuracy in field tests. The system of correcting yield data by the use of air-dried samples is of most value in succulent crops lke sorghum and Sudan grass and is of least value in fine-stemmed plants lke millet, which cure quickly and rather completely. The relation of the moisture content to the stage of development in the plants was studied in alfalfa, timothy, and sorghum. The results were as follows: (1) Alfalfa at Chico, Cal.: Very young (12 inches high), 78.9 per cent; one-tenth in bloom, 77.1 per cent; full bloom, 74.6 per cent; past full bloom, 73.4 per cent. (2) Sorghum at Amarillo, Tex.: Very young, 90.6 per cent; shooting for heads, 87.1 per cent; beginning to head, 84.8 per cent; full bloom, 80.4 per cent; seed ripe, 75.3 per cent. (3) Sorghum at Hays, Kans., varied from 89.2 per cent when very young to 73.2 per cent when seed was ripe, showing practically the same gradations as at Amarillo, Tex. : MOISTURE CONTENT AND SHRINKAGE OF FORAGE. 37 (4) Timothy at New London, Ohio: Very young (10 to 12 inches high), 77.5 per cent; just heading, 76.6 per cent; early bloom, 71.4 per cent; full bloom, 67.2 per cent; leaves drying, 58.6 per cent; seed mature, 51.2 per cent. (5) The excessive percentage of moisture in young sorghum explains the very chaffy character of sorghum hay when the crop is cut too soon, and the 90 per cent loss in weight is an additional reason why sorghum should be fairly mature before it is harvested. (6) The moisture content of any crop at a given stage of maturity is not constant, but may vary with the conditions under which the crop is grown. A study of the rate of loss of moisture in forage during the early stages of curing shows the following results: (1) The approximate losses in the different crops were— Moisture loss. Crop and location. Zhour. | 1Lhour. | 2hours. | 3 hours. | 4 hours. Per cent. | Per cent. | Per cent. | Per cent. | Per cent. 69 BAN a Hata ts © HICO mem rraenciarer a nina eee ere nie oenie me eicen aA cameeeee 17 SOS eee eee AlfalfarateAnlinetonsbanm sca. ens occas eis Seice ccs 6 14 23 28 32 Tall oat-grass and orchard grass at Arlington Farm .. 5 12 24 30 34 mimothyat, Now, London oe. 22. bocce seincinss 6 10 18 25 30 Ore Ruma GHA Sa so eole sa as oe alo ea ae ee et io ae ae 2 5 9 12 13 (2) The rate of loss of moisture after cutting differs in different varieties of the same crop, as well as in different crops. (3) Although the Arabian alfalfa loses moisture faster than the Peruvian or ordinary alfalfa in the first one or two hours after cutting, still the total percentage of moisture is about the same for the three varieties. (4) A high percentage of leaf surface in alfalfa varieties is correlated with a rapid loss of moisture immediately after cutting, but it does not indicate a high moisture content. Studies of the variation in the moisture content of growing alfalfa during a single day at Chico, Cal., show an average of 1 per cent more moisture in the alfalfa at 8 o’clock a. m. than at 3 o’clock p. m. Studies of the shrinkage in hay after storing and variation in moisture content due to changes in atmospheric humidity made with baled oat hay at Chico, Cal., and loose timothy hay at New London, Ohio, indicate results as follows:. (1) At Chico, Cal., where the atmospheric humidity changes radically irom the dry summers to the wet winters, baled oat hay showed a shrinkage in 1914 of 8.1 per cent between June 1 and August 31, and a gain in weight from August 31, 1914, to February 25, 1915, of 5.9 per cent oi the original weight. (2) The results at Chico, Cal., indicate that even baled hay responds noticeably to changes in atmospheric humidity, and that hay dealers are justified in taking into account the shrinkage of their hay when fixing prices. (3) The results secured at New London, Ohio, with loose timothy indicate a shrinkage of 8.6 per cent in one lot and 15.6 per cent in another lot when the hay was stored in a barn for about three months. The effect of a week of rainy weather was indicated by an increase of weight in the loose hay. ADDITIONAL COPIES OF THIS PUBLICATION MAY BE PROCURED FROM THE SUPERINTENDENT OF DOCUMENTS GOVERNMENT PRINTING OFFICE WASHINGTON, D.C. AT 10 CENTS PER COPY V