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commonh- used in the home such as frying, mashing, and holding boiled potatoes
overnight in a refrigerator to be used in potato dishes the following day. These
data are all summarized in Table 10. All values are based on an average of ap-
proximately eight tubers. The values obtained in this investigation are generally
lower than those reported in a similar study by Richardson, Davis, and Mayfield
(37). This difference may be accounted for by the fact that the potatoes used
in this study had been in cold storage for six months as compared with thirty
days' storage in the case of the above authors. It is felt that the data obtained



NUTRITIVE VALUE OF POTATOES



15



in the present study represent average conser\"ati\e figures which may be used
in evaluating the potato nutritionally throughout the winter.

All methods of cooking caused some destruction of the ascorbic acid of potatoes.
The amount of destruction, which varied with the cooking method, ranged from
31 to 80 percent. It appears that the speed with which the internal temperature
is raised, which in turn determines the activity of the oxidizing enzymes, may
be a controlling factor. Boiling whole in the skin, baking, and French frying
appear to be the best methods of cooking potatoes from the standpoint of \'ita-
min C retention.

Table 10. — Effect of Various Cooking Methods on Vitamin C Content

OF Potatoes*



Cooking Method



Ascorbic
Acid



Loss of

Ascorbic

Acid



Vitamin C in an

Average Serving

(5 14 ounces)



Mg. per gm. Percent Mg. LU.**

Raw 0.100 — 14.88 297

Baked 0.069 31 10.26 205

Boiled whole, salted water 0.073 27 10.86 217

Boiled peeled, cut in half 0,053 47 7.88 157

Boiled peeled, sliced . 040 60 5 . 95 119

Boiled peeled, salted water 0.055 45 8. 18 163

Boiled peeled, unsalted water 0.051 49 7.58 151

Boiled whole, salted water; held 24

hours in refrigerator 0.026 74 3.86 77

Boiled, salted water, mashed 0.046 54 6.84 137

Boiled, unsalted water, mashed 0.031 69 4.61 92

Boiled, creamed . 020 80 2 . 97 59

Boiled, fried 0.021 79 3.12 62

Scalloped 0.036 64 5.35 107

French-fried 0.067 33 9.96 199

Boiled whole, cold— salad 0.026 74 3.86 77



*The Green Mountain potatoes used had been stored at 38° F. for 180 days.
♦♦International Units.

In the fall and early winter approximately one fourth of man's dail\- requirement
of ascorbic acid can be obtained from one average serving of boiled, baked, or
French-fried potatoes. In the spring it would be necessary to eat approximately
one and two thirds average servings to obtain the same amount of vitamin C.
The daily requirement of vitamin C for an adult is estimated at approximately
75 milligrams of ascorbic acid or 1500 international units (46). Warmed-over
potatoes and potato salad contained so little ascorbic acid that they cannot be
considered a source of vitamin C.

Tests have recently been conducted at this laboratory^ on the effect of re-
frigerator storage on the vitamin C and moisture content of foods. The foods



'McConnell, J. E. W., and Fellers, C. R. Mass. State College. Personal communication, 1942.



14 MASS. EXPERIMENT STATION BULLETIN 390

were stored in covered and uncovered dishes in home electric refrigerators at a
temperature of 40°-42° F. After two days mashed potatoes had lost 40 percent
of their vitamin C in covered dishes and 50 percent in uncovered dishes. After
four days they had lost 90 percent of their vitamin C in both covered and un-
covered dishes. The loss of moisture was negligible in covered dishes and in-
creased regularly with the length of storage in uncovered dishes. These results
indicate the advisability of keeping mashed potatoes and other vegetables in
covered dishes when stored in a refrigerator in order to conserve their vitamin C
and to prevent them from drying out.

Other Effects of Cooking on Potatoes

, Weibull (53) found no appreciable loss of minerals and solids when white
potatoes were cooked in the peel, but there was a definite loss when potatoes were
peeled before boiling. Griebel and Miermeister (16) conducted similar experi-
ments on boiling and steaming whole and peeled potatoes. The smallest loss in
mineral matter occurred in the steaming of whole potatoes. The losses in total
mineral matter were: — from steaming, whole potatoes 1.4 and peeled potatoes
7.1; from boiling, whole potatoes 5.8 and peeled potatoes 17.0 percent. When
peeled potatoes were boiled in salted water the mineral loss was reduced to about
10 percent. Hill (19) reported that in discarding the water in which peeled
potatoes are cooked about 70 percent of the minerals and antiscorbutic constit-
uents were lost. These losses of water-soluble constituents of the potato during
cooking are due to the leaching action of the cooking water. For this reason it is
to be recommended that potatoes be boiled or steamed with their skins on,
baked, or fried in order to prevent an excessive loss of minerals.

In discussing physicochemical changes produced by the cooking of potatoes,
Sweetman (47) reported that cooking is characterized by partial gelatinization
of the starch, solution of some of the pectin substance, increased digestibility of
the cellulose, coagulation of most of the protein, and more or less caramelization
of the sugar.

Diemair (11) reported that the flavor of baked or roasted foods is largely due
to the formation of histidine bases from the decomposition of proteins. With
baked potatoes the optimum temperature for the formation of these flavoring
constituents was 175° C. (347° F.)

THE PLACE OF POTATOES IN THE AMERICAN DIET

From the above discussion on the composition and nutritive value of potatoes
it is evident that they are a particularly good source of certain of the essential
nutritive elements of the diet. This is particularly true in the case of low-cost
diets where potatoes enjoy a prominent position. Potatoes are primarily important
as a source of energy, vitamin Bi, vitamin C, and iron. Their low cost and the
relatively large amount eaten make potatoes a very economical source of these
elements.

In classifying winter vegetables as sources of vitamin C, Richardson and
Mayfield (38) consider stored potatoes which have been boiled as a good source.
One average serving contained 10 milligrams of ascorbic acid.

According to Stiebeling and Clark (46), the percentage of total specified nu-
trients contributed to the diet by potatoes when 5 percent of the food money was
spent for them, based on families of city workers. East North Central region,
spring 1936, is:



NUTRITIVE VALUE OF POTATOES



15



Percent

Calories 13.9

Protein 10.5

Calcium 8.4

Iron 28.4

Vitamin Bi 35 .0

Vitamin Bg (G) 17.5

Vitamin C 53.9

They consider potatoes one of the cheapest sources of iron, vitamin Bi, and
vitamin C; one of the next cheapest sources of calories, protein, and vitamin
B2 (G); and an economical source of calcium. Potatoes, which were formerly
considered only as a pleasant-flavored vegetable included in most menus, are of
very definite importance to the nutritional well-being of the individual.

In Table 11 the amount of nutrients supplied by an average serving of potatoes
is presented. Many people doing active physical work or on low-cost dietaries
would ordinarily include at least two servings of potatoes in their daily ^ meals.
Potatoes are very good sources of vitamins Bi and C and of iron, for one^serving
supplies over 10 percent of the daily requirement of these nutrients.

Table 11. — Amount of Nutrients Supplied by One Average Serving of
Potatoes (5J^ ounces or 150 grams)



Nutrient



Daily
Requirement*



Amount Supplied
In One Serving



Percent of

Daily Requirement

In One Serving



Energy 3000 calories 127.5 calories 4.2

Protein 70 grams 3 .0 grams 4.3

Calcium 0.8 gram 0.019 gram 2.4

Iron 12 milligrams 1 .65 milligrams 13.7

Vitamin Bi 1.8 milligrams 0. 195 milligram 10.8

Vitamin B2 (G) 2.7 milligrams 0.090 milligram 3.3

Vitamin C 75 milligrams 10 milligrams 13.3



*Man (70 Kg.), moderately active. Recommended daily allowance for specific nutrients. Com-
mittee on Foods and Nutrition. National Research Council. (8).



16 MASS. EXPERIMENT STATION BULLETIN 390

SUMMARY AND CONCLUSIONS

It is the purpose of this bulletin to analyze the published information on the
composition and nutritive value of potatoes and make it available in a con-
venient form for the use of nutritionists, home economists, extension workers,
and other interested persons. In addition, research work carried on in this de-
partment on the vitamin C content of potatoes is reported.

Potatoes should enjoy an important place in the diet because they are good
sources of vitamins Bi and C and of iron. Furthermore, they can be considered
a very economical source of these nutrients and of energy. Most important of
all, perhaps, potatoes possess a pleasing flavor and are eaten with relish by almost
everybody. They lend themselves well to the culinary arts and can be prepared
for the table in many attractive waNs.

The vitamin C content of potatoes seemed to be dependent upon variety.
The amount of this vitamin contained in one variety of potatoes bore the same
relationship to that contained in other varieties whether the samples under con-
sideration were from a single geographical region or a composite from several
states. In general, there was no significant difference in the vitamin C content
of the same variety of potato grown in widely separated states in the United
States. Varietal differences became less significant during storage. Common
and cold storage for 6 months caused the loss of from 16 to 50 percent of the
ascorbic acid of potatoes. Boiling potatoes whole and unpeeled in salted water,
steaming, baking, and French-frying provided the best methods of cooking
potatoes insofar as retention of vitamin C is concerned.

All methods of cooking potatoes caused some destruction of ascorbic acid.
The amount destroyed varied from 3i to 80 percent, depending upon the method
of cooking used.



Nutritionists are in general agreement that many American diets are low in
some important nutrients, including those of which potatoes are good sources.
For this reason the generous use of potatoes is to be recommended, particularly
because of their low cost. During the present emergency every effort is being
made to improve the health of the nation and to economize on all things, includ-
ing foodstuffs. It would thus seem that potatoes have a definite role to play in
our state and national nutrition program.



NUTRITIVE VALUE OF POTATOES 17

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6. Buck, R. E., and Ritchie, W. S., 1938. A new method for the standardiza-

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7. Chatfield, C, and Adams, G., 1931. Proximate composition of fresh vege-

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8. Cummings, R. O., 1941. The American and his food. 2nd Ed. 291 p.

The University of Chicago Press, Chicago, 111.

9. Dam, H., and Glavind, J., 1938. Vitamin K in the plant. Biochem. J.

32:485.

10. Denny, F. E., and Thornton, N. C, 1940. Factors for color in the produc-

tion of potato chips. Contrib. Boyce Thompson Inst. 11(4):291.

11. Diemair, W., 1939. Physiologically active flavoring substances in nutrition

and the possibility of chemically showing their presence. Atti X° congr.
intern, chim. 4:494. C. A. 34:3391.

12. Eddy, W. H., 1929. An improvement in the quantitative assay of the anti-

scorbutic vitamin (C). Amer. J. Pub. Health 19:1309.

13. Fixsen, M. A. B., and Roscoe, M. H., 1938. Tables of the vitamin content

of human and animal foods. Nutr. Abs. and Rev. 7:823.

14. Freas, D. E. H., 1934. A study of the iodine content of Pennsylvania

potatoes. J. Agr. Res. 48:171.

15. Freeman, M. E., and Ritchie, W. S., 1940. Pectin and the texture of cooked

potatoes. Food Research 5:167.

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potatoes by the usual culinary preparation. Z. Untersuch. Lebensm.
52:458. C. A. 21:2341.

17. Hayne, J. A., 1929. Endemic goiter and its relation to iodine content of

food. Amer. J. Pub. Heahh 19:1111.

18. Heller, V. G., Jones, M., and Pursell, L., 1935. Iodine content of Okla-

homa vegetables. Okla. Agr. Expt. Sta. Bui. 229, 8 p.

19. Hill, J. R., 1918. Food wastage in potato cooking. Pharm. J. 100:149.

C. A. 12:2631.

20. Holland, E. B., and Ritchie, W. S., 1941. Trace metals and total nutrients in

human and cattle foods. Mass. Agr. Expt. Sta. Bui. 379, 31 pp.

21. H0ygaard, A., and Rasmussen, H. W., 1938. Inhibiting effect of NaCl on

oxidation of ascorbic acid. Nature 142:293.

22. Ijdo, J. B. H., 1937. Vitamin C content of different species of potatoes.

C. R. Ve Congr. internat. tech. chim. indust. agric. Scheveningen, Holland
1:127. Nutr. Abs. and Rev. 7:612.



18 MASS. EXPERIMENT STATION BULLETIN 390

23. Jukes, T. H., 194L Distribution of pantothenic acid. J. Nutr. 21:193.

24. Kaho, H., 1935. Studies on the potato protein in healthy tubers. Biochem.

Z. 278:235. C. A. 29:8026.

25. Lampen, J. O., Bahler, G. P., and Peterson, W. H., 1942. The occurrence

of free and bound biotin. J. Nutr. 23:11.

26. Lanman, F. R., and Minton, E. S., 1927. The effect of the use of salt in

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27. Levy, L. P., 1937. The effect of cooking on the antiscorbutic value of

vegetables. S. African Med. J. 11:474. Nutr. Abs. and Rev. 7:612.

28. Lyons, M. E., 1939. A study of ascorbic acid in potatoes. Doctor's thesis,

Massachusetts State College. 73 p.

29. Lyons, M. E., and Fellers, C. R., 1939. Potatoes as carriers of vitamin C.

Amer. Potato J. 16:169.

30. Mack, G. L., and Tressler, D. K., 1937. A critical investigation of the

volumetric oxidation method for determination of ascorbic acid. J. Biol.
Chem. 118:735.

31. Mayfield, H. L., Richardson, J. E., Davis R. J., and Andes, E. J., 1937.

The effect of winter storage on palatability and vitamin content of pota-
toes grown in Montana. Mont. Agr. Expt. Sta. Bui. 346, 23 p.

32. McCance, R. A., and Lawrence, R. D., 1929. The carbohydrate content

of foods. Brit. Med. Res. Council Spec. Rept. Series No. 135, 73 p.

33. McClendon, J. F., Barrett, E., and Canniff, T., 1934. The iodine content

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34. McHargue, J. S., 1913. The occurrence of barium in tobacco and other

plants. J. Amer. Chem. Soc. 35:826.

35. Metzger, C. H., Tobiska, J. W., Douglass, E., and Vail, C. E., 1937. Some

factors influencing the composition of Colorado potatoes. Proc. Amer.
Soc. Hort. Sci. 35:635.

36. Mitchell, H. H., and Hamilton, T. S., 1929. The biochemistry of the

amino acids. 619 p. The Chemical Catalogue Co., Inc., New York, N. Y.

37. Richardson, J. E., Davis, R., and Mayfield, H. L., 1937. Vitamin C con-

tent of potatoes prepared for table use by various methods of cooking.
Food Res. 2:85.

38. Richardson, J. E., and Mayfield, H. L., 1941. Vitamin C content of winter

fruits and vegetables. Mont. Agr. Expt. Sta. Bui. 390, 16 p.

39. Rolf, L. A., 1940. The effect of cooking and storage on the ascorbic acid

content of potatoes. J. Agr. Res. 61:381.

40. Schneider, H. A., Ascham, J. K., Platz, B. R., and Steenbock, H., 1939.

The anti-acrodynic properties of certain foods. J. Nutr. 18:99.

41. Sherman, H. C, 1941. Chemistry of foods and nutrition. 6th Ed. 611 p.

MacMillan Co., New York, N. Y.

42. Sherman, H. C, LaMer, V. K., and Campbell, H. L., 1922. The quantita-

tive determination of the antiscorbutic vitamin (vitamin C). J. Amer.
Chem. Soc. 44:165.

43. Smith, M. C, and Otis L., 1937. Hemoglobin regeneration in anaemic

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44. Smith, A. M., and Paterson, W. Y., 1937. The study of variety and virus

disease infection in tubers of Solarium tuberosum by the ascorbic acid test.
Biochem. J. 31:1992.



NUTRITIVE VALUE OF POTATOES 19

45. Stewart, J. J., 1938. Foods. Production, Marketing, Consumption.

739 p. Prentice Hall, Inc., New York, N. Y.

46. Stiebeling, H. K., and Clark, F., 1939. Planning for good nutrition. U. S.

Dept. Agr. Yearbook 1939, 321-340.

47. Sweetman, M. D., 1933. Physico-chemical changes produced by the cook-

ing of potatoes. Amer. Potato J. 10:169.

48. Thiessen, E. J., 1936. Effect of storage upon the vitamin C content of

Wyoming potatoes. Wyo. Agr. Expt. Sta. Bui. 213, 24 p.

49. Tillmans, J., Hirsch, P., and Hirsch, W., 1932. The reduction capacity of

plant foodstuffs and its relation to vitamin C. Z. Untersuch. Lebensm.
63:10.

50. Underhill, F. P., Peterman, F. I., Gross, E. G., and Krause, A. C, 1929.

The metabolism of aluminum. VII. The aluminum content of some fresh
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Vol. 17, No. 7, July.

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57. Wright, R. C, Peacock, W. M., Whiteman, T. M., and Whiteman, E. F.,

1936. The cooking quality, palatability and carbohydrate composition
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Publication of this Document Approved by Commission on Administration and Finance
5m-3-42-9104.



MASSACHUSETTS
AGRICULTURAL EXPERIMENT STATION

Bulletin No. 391 April 1942



A Survey and Study of

Spontaneous Neoplastic Diseases

in Chickens



By Carl Olson, Jr., and K. L. Bullis



Neoplastic diseases (tumors) cause much loss to the poultry industry. This
collection of cases of neoplasia gives information of the characteristics and
relative incidence of the different types.



MASSACHUSETTS STATE COLLEGE
AMHERST, MASS.



A SURVEY AND STUDY OF SPONTANEOUS NEO-
PLASTIC DISEASES IN CHICKENS

By Carl Olson, Jr.,' Research Professor, and K. L. BuUis, Assistant Research
Professor of Veterinary Science



CONTENTS



Page

Introduction 2

Source of material and methods 3

Descriptions of specific forms of neoplasia

observed 5

Lymphocytoma 5

Myelocytoma . . . \ 18

Fowl leukosis 20

Fibroma 21

Myxoma 22

Fibrosarcoma 23

Osteochondrosarcoma 24

Fibrochondrosarcoma 24

Histiocytic sarcoma .24

Neurogenic sarcoma .25

Epithelioblastoma .27

Hepatoma. . .50

Cholangioma 30

Thymoma . . 31



Page

Hemangioma 32

Lymphangioma 34

Leiomyoma 34

Rhabdomyoma. 36

Mesothelioma. . . 37

Melanoma 38

Embryonal nephroma 38

Carcinosarcoma 30

Teratoma 42

Discussion 43

Incidence 4.5

Distribution of lesions 4")

Correlation between tentative and final

diagnoses 49

Concomitant tumors 54

Summary and conclusions 55

References 55



INTRODUCTION

Neoplastic diseases among animals take their greatest toll from the domestic
chicken, where they represent a serious economic problem. This fact has led
to the development of many research programs seeking a solution to the prob-
lem. A number of types of neoplasia may occur in the chicken, although it is
generally recognized that those involving the cells of the hmphoid system are
the more common and, therefore, the more serious to the poultry industry. Such
recognition, however, tends to overemphasize the importance of the hmphoid
type of tumor and to minimize the significance of the other tumors. Even though
the other types are relatively infrequent in chickens, they should not be dis-
regarded, because as a group they are responsible for a share of the loss. Another
important rea.son why all types of tumors should be considered is the problem
of differential diagnosis. Modern science is devoting much time and energy to
the study of the causes, cure, and prevention of neoplastic diseases in animals,
as well as in man. The study of spontaneous cases of neoplastic diseases in chickens
is an important phase which has perhaps suffered from lack of attention and
careful investigation. The usual practice of investigators has been to collect
and describe a group of cases dealing with a specific neoplastic disease. Such
data do not give information on the relative frequency of different types of tumors
in chickens. The reports of Schneider (29) and Curtis (3) provide some informa-
tion on the general incidence of neoplasia, but they lack details as to the specific
types of disease encountered. Eber and Malke (4) have reported on 371 cases
of neoplasia found in 11,903 chickens submitted to the University of Leipzig
for examination over a period of 32 years. In the survey made by Goss (11) on
six flocks of chickens totaling approximately 24,000 were 1446 tumors. The
majority of tumors (991) were classified as "leucotic" tumors and no attempt
was made to further subdivide this large group into cases of lymphocytoma,
leukosis, myelocytoma, etc.



'The authors wish to acknowledge the aid of other members of the Department of Veterinary
Science in various phases of this study, particularly Drs. J. B. Lentz and H. Van Roekel, Mr.
O. S. Flint, and Miss M. K. Clarke.



NEOPLASTIC DISEASES IN CHICKENS 3

Cases of tumors have been collected here for a period of several years. This
accumulation has now reached a size sufficient to merit collective study and
constitutes the basis for this bulletin. This study may be expected to contribute
to the knowledge of the morphological characteristics of the various types of
neoplasia as well as to provide information on the relative incidence of the specific
types. No attempt is made to provide a comprehensive review of the literature
since this was adequately done by Heim (12), with reports up to about 1930.

SOURCE OF MATERIAL AXI> METHODS

The cases of tumor were derived from three general sources. The principal
source was the laboratory of the Poultry Disease Control Service maintained
at the Massachusetts State College. Commercial poultry flocks of Massachusetts
submit chickens suspected of disease to this laboratory for examination and
diagnosis. During a two-year period from December 1, 1937, to December 1,
1939, all specimens received by the diagnostic laboratory and suspected of neo-
plastic diseases at the time of necrops>- were examined histologically. Those
cases found to be neoplastic were included in Collection A. A second source of
material was a flock of chickens maintained at the college by the Department of
Poultry Husbandry for genetic study. Some of the chickens that became ill or
died were submitted for e.xamination, and cases of neoplasia observed between
December 1, 1937, and December 1, 1940, were included in Collection B. A
third source of material (Collection C) consists of cases of neoplasia collected at
random from various sources, such as cases found in birds serving as controls
for experimental work and cases studied prior to December 1937 on which ade-
quate information was available.^

A tentative diagnosis of the neoplasm was made at the time of necropsy ia
the majority of cases. These diagnoses were later correlated with the final diag-
nosis, which was arrived at with the aid of histological examination. This was
done in an effort to determine the accuracy of a diagnosis made as a result of a



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