f\ 1 1 1 r ' if G L910. ( . S. DEPAR rMENT OF AGRICULTURE, Bl i; I A l OF PLANT INDUSTRY— Circular No. 47. (JALLOWAY, Chiel of Bureau. PRICKLY COMFREY AS A FORAGE CROP. II. \. VINALL, Scientific Assistant, Office of Forage-Crop i \\ ESTIG ITIONS. WASHINGTON ! GOVERNMENT PRINT!' UNIV OF FL LIP DOCUMENT^ Dp OEPOSITORY BUREAU OF PLANT INDUSTRY Chief of Bureau, Beverly T. Galloway. As$ista7it Chief of Bureau, Albert F. Wi Editor, J. E. Rockwell. Chief Chrk, James E. Joni s. [Cir. 47] PRICKLY COMFREY \S A FORAGE CROP." INTRODUCTION Prickly comfrey {Symphytum asperrimum Donn) is a perennial herbaceous plant, a native of the Caucasus region of Europe, which was introduced into England as early as 1801. Apparently it was first grow n in the United States near Richmond, Va., in I s 7 ( ; . The only recorded importation of this plant by the Department of Agri- culture was made in February, 1899, from France, in L830 it attracted attention in England as a forage plant, and from thai date until 1876 or later some little interesi was exhibited in its dissemina- tion by agriculturists. Thomas Christy, jr., of London, was especially prominent in it's advertisement and published a lengthy article6 descriptive of its value as a food for hogs, sheep, and dairy cows, especially as a soiling crop and in the form of ensilage. Although prickh comfrej was grown rather extensively years ago in Europe and to some extent in the United States, it has never attained any considerable importance in either country as a forage crop. At the present time it is probably grown more generally in Germany than in an\ other country, and its success there may be ascribed to the intensive methods of cultivation employed on small farms, a practice which calls for some crop that will re-pond with \ ields to heavy applical ions of fertilizer. Only under such meth- ods can the yields of forage mentioned in reports from Germany be expected. None of the government experiment stations in European countries have seen lit to commend prickly comfrey in their reports -" far as noted. f Prickly comfrey has been grown a- a forage crop to .-nine extent in Europe, and in scattered instances with success in this country, Its general standing, however, lias not seemed to warrant an extended trial by the Department of Agriculture. Recently advertisements making exaggerated claims regarding its value as a forage crop have appeared in newspapers ami circulars, it is therefore deemed advisable to pub- lish in a concise form the results of tesis of this crop at several state experiment sta 1 ions, together with a brief description of tin- plant ami directions for its culture. This will enable intending growers to draw their own conclusions as to its probable value for their purposes. I'. T Galloway, Chiefo/Bu ^Christy, Thomas, jr. Forage Plants and Their Economic Conservation li New System of "Ensilage," Part 1. London, is;;. [Cli 4 PRICKL5 COMFREY AS A FORAGE CROP. DESCRIPTION OF PRICKLY COMFREY. The seed stalks of prickly comfrey reach a height of 2 to 4 feet and are surrounded by numerous long, heavy, rough leave- of a dark- green color somewhat mucilaginous in texture. (See fig. 1.) The bright-blue flowers are borne in nodding, one-sided cluster- (fig. 2, .1 . The roots are large and fleshy and in loose soil will reach a depth of Sot* WmMmmm j^K-SBsppip Fig. I a planl »f prickly cotufrey in bloom. 8 or 9 l'eet. The plant is hardy and will endure considerable cold or drought, making a very rapid growth when conditions are favorable. PROPAGATION OF THE PLANTS. A.lthough the prickly comfre} produces targe crops of seed, only a small percentage of this seed will germinate, so it is generally found more practicable to plant new held- by division of the roots than by l< if. 171 PBK KL^ I i'\| ! HE\ A.S \ l , h; \i,|. ri;,.|' 6 PRICKLJ COMFREY \s A FORAGE CROP. seed. These root cuttings may be cither crown cuttings (fig. 2, J! I or transverse sections of the lower taproots (fig. 2, C), and they may be quite small, so that the number secured from a single plant will be considerable even in one year. They are planted in rows, usually about 3 feet apart each way, or 3 feet between the rows and l\ to 2 feet apart in the row, the distance depending on the fertility of the soil. When first planted, the young sets must he given frequent and thorough cultivation. The sets made from crown cuttings usually bloom the first year, while those made from pieces of the taproots will not bloom as a rule until the second reason. CULTURE OF THE CROP. Cultivation should be continued after each cutting until the plants are large enough to shade the ground, and a light top-dressing of manure should be given the field after each cutting if large and fre- quent crops are to be expected. The cuttings should always be made before seed has formed. From three to six crops a year may be ob- tained, and in good soil a field is supposed to last from fifteen to twenty years without replanting, returning a yield of 10 to 40 tons of green feed per acre each year. VALUE OF PRICKLY COMFREY AS A SOILING CROP FOR DAIRY COWS. It is as a soiling crop for dairy cows that comfrey has proved of most value. Dr. Henry Foster, of Clifton Springs, X. Y., has been in the past the most enthusiastic advocate of comfrey for this pur- pose." Doctor Foster top-dressed his fields with manure after each cutting and cultivated thoroughly. In this way he claimed to have secured a, yield of 50 tons per acre in five cuttings. According to his statement the cows ate it greedily, and no other crop equaled it in producing quantity and quality of milk. At the New York Agricultural Experiment Station'7 dairy cows at first refused to eat green comfrey. Coin meal was then sprinkled over the comfrey ill the manger, hut it was knocked oil' and licked up from the bottom of the feed boxes. As a last resource, salt was scattered oxer the comfrey and the animals were thus induced to eat it. They soon became fond of it and afterwards ate it readily with- out salting. VALUE OF PRICKLY COMFREY FOR FEEDING HOGS. Experiments were carried on at the New "> oik Agricultural Experi- ment Station'' in which two lots of hogs, averaging 64 pounds each, were led during three weeks all the comfrey they would cat. in addi- a Report, New York Agricultural Experiment Station, L887, \> 72. 6 Bulletin 22, n. s., W« fricultural Experiment Station, pp.292 295. I ' Lr. 17 1 i ■ i ; i ■ i \i i'i;i:\ as \ fokaue chop. , t ic hi to "a little com meal.'' The average loss in weight of one lot was 0.9 pound per week, and of the other lot 1.6 pound-. This loss was not due to lack of capacity, since in a similar experiment with mangolds, which contained as great a percentage of water as the eom- frey, the hogs ate twice a> much. Another test with older pigs was made, using for the first six weeks a ration com pose, I entirely of grain : the next four weeks a rat ion t hat was ."ai per cent coin ensilage; and the remaining five weeks of the period a ration containing 50 per cent of comfrey. The comfrey was \'n\ I'reshK cut and contained an average of 86.7 per cent of water. In considering the cost per pound of gain, the green comfrey was rated at 81 a ton. In one pen the comfrey and ensilage were salted, while in another pen the green feed was not salted. Neither lot of j)ii^s made a profitable growth while comfrey was fed, and the cost per pound of gain in live weight for the period they were U'A comfrey was 9.53 cents in the pen where sail was not applied and 6.12 cents in the pen where salt was applied, as against 3.38 cents in the first pen and 3.07 cents in the second pen when ivd the grain ration. VALUE OF PRICKLY COMFREY AS HAY OR ENSILAGE. Regarding the use of prickly comfrey, the New York Agricultural Experiment Station reports" as follows: "Our trials indicate that it is of no value either for hay or ensilage. Its use, therefore, is con- fined to that of a soiling crop." In Europe it has been used to sonic extent for silage, hut the watery and gummy nature of the leaves is apt to cause it to heat in the silo and acquire a disagreeable odor. CROP YIELDS. from i | to 16 tons of green matter per acre are reported by the New York Agricultural Experiment Station." It> tons by the Ver- mont station.'' f>! to 17 ' tons by the North Carolina station/ and .".."» \ tons by t he Wisconsin stat ion. ' In dry matter the Wisconsin Agricultural Experiment Station reports'' u yield of 6,475 pounds of comfrey to the acre, compared to 7,'.»s7 pounds of red clover. The Pennsylvania Agricultural Experiment Station reports' the yield per acre of digestible material in comfrey. Kafir corn, and cowpeas to he as follows: N'ew York Agricultural Experiment Station, 1888, pp 332 and :;.'..'■ IS89, [>p. 221 and 222. Report, Vermont Agricultural Experiment Station, 1889, p lletin 168, North Carolina Agricultural Experiment Station, pp. 129 132. Re] irt, Wisconsin Agricultural Experiment Station, 1889, pp. 207 ami '.'I I. ' Bulletin 6, Pennsylvania Agricultural Experiment Station, pp. lilt; • 7| PRICKLY COMFREY. AS A FORAGE CROP. Fat Crude fiber X i t rogen-Iree extra Protein Total digestible matter Total green matter. . . . Prickly eomfrey. Pounds. 30.5 35.3 623. l 221.0 909.9 1G, 500.0 Kafir corn. Cowpeas. Pounds. 34.2 33.2 ' 907.8 119.4 1.094. 0 1 1 . 000. 0 Pounds. 53. 9 247. 0 090. 0 280.9 1,271.8 14.500.0 These figures indicate that although the yield of green matter is greater in prickly eomfrey, the real food value is likely to be less than that of the commonly grown forage crops. COMPARISON OF PRICKLY COMFREY AND RED CLOVER. At the Wisconsin Agricultural Experiment Station " equal areas of red clover and eomfrey were planted in 1887. The eomfrey was top- dressed heavily with stable manure. Yields of both were determined the second year, the cuttings being made with a scythe. The red clover returned 26 tons of green feed to the acre in three cuttings, and the eomfrey 33J tons. Samples were taken of the cuttings of both crops and the dry matter determined. The red clover pro- duced 23 per cent more of total dry matter and 25 per cent more protein in three cuttings than the eomfrey did in four. A more important difference between the two crops is in the lesser cost of planting and harvesting the red clover and its greater palatability to stock. It would seem that prickly eomfrey can not compete with red clover as a forage crop for the general farmer. COMPARISON OF PRICKLY COMFREY AND ENSILAGE CORN. In Michigan b eomfrey was grown side by side with ensilage coin, and the trials "taught emphatically that in the soil and climate existing at the Michigan station corn is far superior as a forage crop i o eomfrey." COMPARISON OF PRICKLY COMFREY AND ALFALFA. The older planting of eomfrey at the New York Agricultural Experiment Station during 1889 gave a yield of 14 tons of green matter per acre. Alfalfa during the same period yielded more than 1() tons of green matter per acre. DISEASES OF PRICKLY COMFREY AND INSECT ENEMIES. Comfrey has been grown at the North Carolina Agricultural Experi- ment Stal ion since L899.c It grew well hut was injured by both cater- pillars and a fungous disease, which reduced the crop to two Or three a Report, Wisconsin Agricultural Experiment Station, L889, pp. 207 and 211. & Bulletin 47, Michigan Agricultural Experiment Station, pp. 43 and 44. o Bulletin 7:!. North Carolina Agricultural Experiment Station, p. •">!>. [Cir. 47] I'Kli K I . > t'OMFHKJ VS \ b'OKACil CHOP. '.I cuttings each your, while many kills were killed out entirely l>y the disease. When planted on a thin soil with a Hard clay subsoil, the third growth withered up during the period of drought and the plants remained dormant until the following spring. EFFECT OF PRICKLY COMFREY ON THE SOIL. The soil in an <>ld eomfrey field is usually left in mdition, owing i" frequent cultivations and to the top-dressings of barnyard manure. The large, fleshy roots of the eomfrey also penetrate to a considerable depth and add humus to the subsoil, where it is usually wanting. Analyses of the materials removed from the soil,0 however, show that were n not for the constant application of fertilizing material the growing of eomfrey would be decidedly injurious to the soil. Assuming 20 tons of green material to the acre as an average crop of eomfrey, there would be removed from the soil 165 pounds of nitrogen, 65 pounds of phosphoric acid, and 74 pounds of potash. From the present knowledge of prickly eomfrey, it is advisable to experiment with it only on a small scale as a soiling crop. There seems little to justify its extended use in a region where alfalfa or red clover will succeed. Large yields have nol been obtained without heavy applications of fertilizer, and a comparison of prickh eomfrey with the forage crops already in use has usually resulted unfavorably to the eomfrey. Approved : James Wilson, S\ cretary of Agricultun . W vshington, I). ('.. Dea mbi r 10, 1909. port, Canada Experimental Fair p. 201 = 7| Digitized by the Internet Archive in 2013 http://archive.org/details/freyasOOunit UNIVERSITY OF FLORIDA 3 1262 08928 9879