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Lea diagrammee suivants illustrent la mithoda. 1 2 3 1 2 3 4 5 6 Miaoc c rr mouniON tbt cmait (ANSI and ISO Tf ST CHART No. 3) I.I Ui U2S MTS m ^^ ^^" lit |3J ■ 2.2 111 |» ■^ HI |4£ 12.0 |i.?' iiu 1.6 A /APPLIED IIVMGE Inc 165J Ent Uoin Street RochMtcr, Nm York 14609 USA (7t6) ♦82 - 0300 - Phon* <716) 2M-S9a9-Fo> Dominion o. Canada DEPARTMENT OF AGRICULTURE Dominion Expbrimrntal Farms DIVISION OF BOTANY THE BLACK OR STEM RUST OF WHEAT A POPULAR ACCOUNT OF THE NATURE. CAUSE AND PREVENTION OF GRAIN RUST BULLETIN No 33 SECOND SERIES MARCH. 1917 fi,n li °' *•"' "°" MARTIN BURRELL, Minuter of Agricnlture "^•^•^ Ottawa. Ont. C212 Exp. Farm Service Bull, and ser. Dominion of Canada DEPARTMENT OF AGRICULTURE Dominion Experimkntal Farms DIVISION OF BOTANY THE BLACK OR STEM RUST OF WHEAT A POPULAR ACCOUNT OF THE NATURE, CAUSE AND PREVENTION OF GRAIN RUST BULLESTIN No. 33 SBOOND SBBIBS MA.ROH. 1917 PablUhed by the direction of the Hon. MARTIN BURRELL, Minirter of Agriculture. Otuwa, Ont. The Honourable, The Minuter of Agriculture, Ottawa. Ottawa, May 1, 1917. Sir:— I have the honour to sulirait herewith the manuscript of Hulletii, Xo. 33, of the Second Series, entitled "The Black or Stem Rust of Wheat", it being a popular account of the nature, cause and prevention of the disease. This is a very timely publication on the 8ub.iect of rust and is written in •uch a popular style that its appearance «t this time should be most useful to the farmera of the prairie province*. The bulletin affords a good idea of what rust is, and gives, in concise form, such information as is nt presint available on how to guard against its ravages. I would recommend, therefore, that the printing of this bulletin he f. 'o- ceeded with as soon as possible*. I have the honour to be. Sir. Your obedient servant. J. H. GRISDALE. Director, Dominion Experimental Farma. BLACK OR STEM RUST OF WHEAT IHTMIIUUTIOII TbU •ccount hu betn prap»r*.I. partly to amplify the 51lu«tr«t#d colourwi porter on the ume lubject belnf iMued by the Deptrtmf . , and partly to meet the many Inqulriee received in thia laboratory, relating to the nature and caoai. of grain rtwt, about which there exiit among farmeri and o»heri not alwaye correct theoriet. It is thought deairable to deal with the lubject in thia preliminary ••■count, in a manner easily underatood by the practical farmer w' -^e time "d faci .- tiea do not permit him to enter deeply into a mibject of-»fter all-«> higniy technical a nature. The term "mat" ia familiar to the tanner, but oar exper- ience ha. .hown that there are a large number of farmer- who only know the term and not really the dieeaie; thin ia demomitrated every year by the many ■ample, and inquiriea relating to ru.t which are received, l.ut which on examination bear no resemblance to the dieeaae. unrsEAZi DisTF.* nxxMi or van It it an e«tabli.hed fact that there exiat .everal kind, of groin ru.t. juat a. different from each other aa wheat differ, from oat. or barley. Moreover, the peculiar mode of development of our commoneat grain ru.t-the blacl or .tem ru.t-dnring certain perioda in which it may differ in appearance to » remark- able degree, haa given ri.e to the popular belief that there are two kind, of ru.t-the Red Ruat and the Black Ruat^of which two the latter alone i. popuarly regarded aa aeriou«ly injuriou.. The truth, however, U that both the .o-called red and black ru«t are merely .tage. of the aame fungua causing this destructive diseaae. The disease commonly known as rust is causod by extremely minute parasitic plants which live upon the gram plant ana the resourcf f Jod manufactured by this plant for its own sustenance. Th« utiluatic f food by the small but very vigoroua parasite often causes sen. us inju , to the plant upon which it lives, or which acts however invc.uutyu.v aa it. host; hence the term "host plant" which is uow commonly ue.-' m referring to similar exi.ting relations. . ._ . ccoio^t The ru.t-causing plant, are so small that a ... d len. « barely sufficient to make out the most prominent characters. By means of the powerful lenses of a microscope, the characters of the various kinds of rust become so prom,- Dent that the differences between them are more or less readily distinguished, and these small plant, may then be seen clearly to be as different as wheat, oats and barley are seen to differ with the naked eye. When wheat, oats or barley is affected by rust, the first symptoms that mav be recognized are small yellow, orange, red, brown or black circular or linear spots covering leaves, stem, and ears of the host plant. The more severe the attack is. the more numerous are the spoU; a few spots are present every year on growing plants, the disease being rarely absent. These spots are most characteristic ; they do not consist of dead areas of the portions attacked, they are not thinner than the normal thickness of the leaf. For instance, they do not resemble pin pricks similar in nature to injuries due to sucking insects, but they are at an early age slightly raised minute blisters or longish narrow wales, as if "something" within the interior of the leaf or other parts attacked were making an effort to push through the skin (technically the epidermis of cuticle) of the leaf. Indeed, this is exactly what occurs. Before the yellow, red, orange, brown or black wales become visible, they have already been present in the leaf or other tissues, slowly gathering and pushing against the leaf surface with an ever increasing force, until the skin is burst and what was formerly covered and hidden by it appears on the surface in the form of various coloured spots. This process can be easily watched by an interested observer in possession of a fairly strong hand or pocket lens. * The colour of the spots is due to what may be described as a fine powder — in reality the seeds of the rust plant. Technically, one speaks of plants of this kind as "fungi" and of their seeds as "spores." The colour is to some extent a guide either to the stage of development reached by any one species of rust, or to the peculiar kind of rusts present. Thus pale yellow orange cushions are nearly always associated with yellow rust, brownish spots with brown rust, black spots or stripes with black rust. These are very popular distinctions ; there are other features visible under the microscope which clearly separate one fungus from the other. THE 0ATT8B OF B08T Ain> THB INFEOnOK OF THE WHEAT PLANT We shall now consider how the fungus originally entered the interior of the leaf or stem of the host plant, what took place while within it and what will further happen when it has broken through the skin. The most common and injurious of all rusts is undoubtedly the so-called "Black or Stem Rust" which is caused by the minute parasitic fungus technically known as Puccinia graminis, Pers. This rust is found on wheat, oats, barley, rye, and a large number of wild and cultivated grasses. The symptoms may be observed on any part of the plant with the exception of the root. Black Rust is responsible for nearly all the losses to grain in Western Canada. Oc jasioually epidemics such as that of 1916 occur, which cause a loss of hundreds of millions of dollars to the national wealth. Its life history is there- fore fully discussed in the following pages. Farmers are most concerned with this rust, as it is so destructive to grain, though it does not actually commence its life cycle on grain, but for a better understanding we shall start our con- sideration with this plant. • The poRsemlon of ■ porket lens la a great asset to the fanner: with it he can often recotrntxe Terjr minute enemleH. which are so dangerous because so minute, and not risible to the nakad aye. A yery excellent lens for use Is the "iO dlamater Coddlngton." niniiufai'tured by Mcasn. B«aaeh amd Lomb, Rochester, N.Y.. and sold In Canada for about fl.BO. In using such a leni, hold tkc object to be examined In the left band, allowtng the light to fall npnn It. then hold the lens with jour right hand flush on the object, keeping the eye about 4— « Inches distant then begin rery slowly to raise the lens away from the object, keeping your eye steadily fixed •n the centre of the lens until the object to be examined appears rery prominent and s« roui-b enlarged that In the case of rust, all the details described above become clear and conspicuous. It Is well to try this proceeding on the print of a book or newspaper. THE BED 0» nnCMEB STAGE OF STEM BU»T We have already described in a general manner, the process o^''*' i).'* of the fungus until the spores appear through the ruptures in the skin. The spore-raasses that appear at first are rusty red in colour, hence the popular lerm • ReTRust" (see coloured poster on Black or Stem Rust of Wheat, which is reproduced in black and white in this issue, left panel centre stem and left bottom stem showing red rusty spots). The rust spots may be so numerous that when a leaf is drawn between finger and thumb they will become covered with reddish brown dust. At the time of threshing last year's crop, the amount of "^^^''n '''"f. wnrn in the air wai so enormous that quantities could be scraped off the coats worn by the men serving the machine. This red form of spores is generally referred to as summer spores, because when they are first noticed it generally is during summer, but some of them may be found in fall on late maturing wheat, indeed instances arc known of some having passed through the winter. These spores are seeds inasmuch as they have the capacity to germinate only they do not germinate in the soil and grow there, but do so instead right on the surface of the leaf or stem of the same plant, or of °"f »i^°""°f P^"*^ or plants some conaiderable distance away, for it is easily understood that the spore dust must be blown about by the wind, which in fact does occur and is one of the means of the spread of the disease. Rust sporei are produced in these spots by millions (compare coloured poster right hand, upper half "Red Stage of Stem Rust" The uppermost square shows a smaU piece of leaf tissue with two rust spots enlarged twenty times. Here, the rupture of the cuticle is easily seen, as well as the red dust bursting through the ruptures composed of the red or summer spores referred to. Immediately below this square, these spores are shown enlarged five hundred times. As will be seen, they are attached to short co ourless stalks and are of oval shape with golden yellow contents and a thin-walled membrane, covered with very minute prickles). Every spore produced is capable of germination under suitable conditions. Nature is so lavish and generous in the production of seeds and spores that, if every seed or spore would develop into a plant, in the course of a very few years there would be left only the most persistent plant that had succeeded in crowding out all the others. It is, therefore, safe to say that most of the seeds or spores produced do not find the necessary conditions to start into life. Seeds do not grow on rocks, do not germinate without moisture. It is just the same with fungus spores. They are far less securely protected from drought than seeds, and milUons dry up and die. Moisture is indispensable for their germination, though it be only what we term the humidity of the atmosphere. During dry, windy weather, rust epidemics do not develop, but we know that a few still, humid days miraculously favour the spread of rust Now during the summer under favourable conditions, the spores germinate and produce a very fine "rootiet" which penetrates into the interior of the plant. In the tissues and celU composing the host plant, the rootlet finds ready-made food in plenty, rimilsr to what ocean when a leed is pla-ted in fertile eoil. The original "rootlet" now branchea and ramifies in all directions, permeating the cella of the hoat plant, which during this process does not appear to be injured. When finally the ftinguB plant has existed in this condition long enough, it produces from its mass of cells a number of primary spore-cushions, within the interior of the host plant. These grow in size and struggle for an exit, which is only through the skin or cuticle of the plant. This cuticle at first bulges out and finally bursts or ruptures, when a mature crop of spores appears on the outside. This process takes from eight to ten days, i.e., from germination to spore production, and continues throughout the summer as long aa there are to be found green leaves of cereals or grasses to afford a suitable medium for their growth and development. Thus far, we have been dealing with the summer stage, or what is termed "Red Rust," and erroneously con- sidered to be a disease different from the later stage. THE VLKOK OB WISTBB 8TAOE OF 8TBM BUST The summer stage is soon followed by another and that on the same host plant and in close association with the spots produced by the summer stage. This new form is termed winter stage, but is popularly referred to as "Black Rupt." The term winter stage is not quite correct either, since this stage may appear as early as August, but, generally speaking, the term winter stage is used in view of the fact that this new type of spore does not germinate until the following spring. When the red rust stage changes into the black rust stage the spots be- come decidedly more linear in shape and appear as long black sooty stripes. (Compare coloured poster left panel the affected part bearing an undeveloped ear and the culm to the extreme right of panel showing black stripes). When this stage is reached, the greatest damage has been done and the fungus is aware that the life of the host plant is doomed, hence, according to nature's law, the fungus must now look after its own perpetuation which it does by the production of specially thick-walled winter spores, which are so protected as to withstand even very severe winters. (Compare coloured poster right panel, two lower squares, of which the upper shows the change in colour that has taken place. Note no dispersal of spores in this condition, but compact crusts composed of winter spores. Below, the square shows winter spores enlarged five hundred times. In shape they will be seen to differ very considerably from the summer spores, as well as in colour). BED STAGE AM) BLACK STAGE OP STEM BUST BELONG TO THE HAitra rUKGUS It is again stated here that while to the layman the red stage appears to be so absolutely different from the black stage, which as far as structure is concerned, is quite correct, yet the former is merely an earlier stage in the life history of Stem Rust, while the latter is the final or mature stage. This is no and spores from those of the winter forms; some indeed, produce still more rare occurrence in fungi, many of which have quite different summer forms kinds of ■pons, all of which are merely itages in their development towudi maturity. In insect life of course, everybody is quite familiar with the re- markably different forms and shapes and indeed modes of life through whieh many of them pass in the course of their life cycle. Every schoolboy is nowa- days familiar with the life history of an ordinary butterfly or moth. The caterpillar, chrysalis and adult insect are merely stages of the same individual insect. This example may serve as an illustration explaining the close rela- tionship existing between the various stages of the rust fungus. Aonov or the funoub on the host pzjutt It should be fully understood that the damage done to the grain crop is the result of the strictly parasitic mode of life of the fungus as previously indicated. A sound wheat plant consists of a large number of cells and sap- conducting vessels, all of which are required to perform their individual func- tion in storing, supplying and making available food supplies to the plant, to bring it to maturity, that is, to enable it to ripen its seeds which are the "grain" of commerce. A slight rust attack involves only comparatively few individual cells of the host plant and the damage is slight. But when the attack is 1 3ver« the plant suffers much more and may be killed before any grain is produced. This process might be described as follows. The grain, during its de- velopment, gradually becomes filled with food reserves which it takes from the growing plant. If a fungus uses part of this supply, the grain suffers pro- portionally. The result is a more or less shrivelled, small and immature grain. In bad rust years, an acre may yield a small quantity of grain, but this is generally as useless for seed purposes as it is for milling. Thus, it will be seen that the loss from a rust epidemic is not only an immediate one, owing to loss of yield, but there is, as a further consequence, a lack of plump, vigorous seed grain. THE BBLATION OF STEM KXTBT TO THE P^UBEEBT It was stated in the beginning that the subject of grain rust is one of a highly technical nature. The life history of this fungus is certainly a most complicated one as far as our present knowledge goes, indeed there are some phases wUch, though familiar to the close observer, are nevertheless not thoroughly understood. In the foregoing sections we have discussed the life of the rust fungn^i as it is passed on the wheat. We must now consider another phase of the life history of the Stem Rust, whieh occurs on quite a different host plant, vii., the Barberry. In passing, let us recall the reference already made to the re- markable but different modes of life found in the life cycle of one and the same insect, giving as a further example here, the common dragon fly, which passes one stage in water and another in the air. Before discussing the importance of Canadian conditions in relation to this change of host plants on the part of the fungus, we shall briefly relate how it occurs. 10 The winter apores of nut germmate in spring, but even though they may be Mwn thickly on the surface of growing grain plants, they have not been known at any time to push a 'rootlet' through the pores of the epidermis like the summer spores. They cannot, under any circumstances, directly infect any of the coltiTated or wild plants generally subject to rust. What could be aceompliahed easily with the summer spores on wheat plants could not be raeceaafully carried out with these winter spores, although they were tested as to their germinative power. What became of these winter apores and what purposes they fulfilled was long a matter for speculation. It may, at this stage, be of general interest to mention the popular belief regarding the common barberry in Europe. Practical farmers aa early aa the middle of the 17th century, regarded the barberry aa having a cloae rela- tion to the rust of grain. Thia common ahrub waa looked on aa having a mysteriously injurious influence on grain. Since that time, this belief has been reiterated again and again, and indeed aa early aa the year 1660, the munici- pality of Rouen (France) issued a decree ordering the destruction of thia shrub. Nearly one hundred years later the State of Massachusetts promul- gated an order demanding the deatruction of all barberry buahes. In 1776 Withering, a well known naturalist in England, recommended "That thia ahrub should never be permitted to grow in "com" (grain) lands, for the ears of wheat that grow near it never filled." And so, owing to what appears as a somewhat popular superstition, the barberry was regarded aa a menace to grain culture. It waa not until the latter half of the 19th century, i.e. in 1865, that Anton de Bary, a famoua Oerman botaniat, determined by scientific experiments that the life cycle of thia mat waa continued on the barberry. He found that the winter spores of Stem Rust on wheat produced, on germinating in spring, an- other form of spores, which in their time germinated on and entered into the leaf tissues of the barberry. The infection produces very prominent, bright red-coloured apots on the leaves of the barberry, the apots often showing a pronounced yellow margin. (Compare coloured poster top panel, showing the shrab barberry in flower and fruit and four leaves bearing the bright coloured spots resulting from an infection with winter spores from stem rust of wheat). In greenhouse experi- ments conducted at the Central Experimental Farm, infections of barberry leaves were produced from over-wintered wheat rust-spores in some 12 days. The spots soon assumed a very bright red colour, though only of the size of a pin prick at first. They began increasing in size, until after some four weeks from infection there was produced a crop of spores in minute cluster-cups pushing through the lower surface of the barberry leaves. Under favour- able conditions, however, the time required for thia atage might be much leaa. Reference should be made here alao to the production on the upper leaf aurfacea (corresponding to the spots) of small droplets of a sugary, gummy substance, which contain very minute sporelike bodies, technically known as spermatia — about the function or purpose of which, up to date, nothing is known. The spores produced in the cluster-cups of the barberry again differ in shape and size from any described before. These spores refuse to germinate on the bar- II berry, but when Bown on the leaves of a grain crop, the result is the production of the firit crop of summer spores of stem rust already described in detail. Lim HUTOBT or ITEM RUST OF WHEAT IK SHOXT This is to recapitulate briefly the life history of grain rust. On the leaves of barberry are produced early in the year "spring spores." These do not infect the barberry, but go on to the grain pro.hicing "summer spores" followed later on by "winter spores" on the same host. The winter spores hibernate on the stems of cereals and other grasses; they cannot cause a direct infection of the growing grain plant, but infect the barberry, and thus the life cycle is completed. THB BOLB or THE BABBBRBT IK OAKAOA The barberry (Berberis vulgaris, L.) is not a native shrub in the Dominion of Canada. It has been introduced from Europe, because of its hardiness and somewhat ornamental value. It is by no means even a common ornamental shrub, such as lilac for instance, but occurs in private grounds and may have escaped from cultivation, at any rate in the Eastern section of the country. The position of the barberry in the life cycle of the grain rust cannot be disputed. This shrub certainly serves as an intermediary host plant, but although the discovery is primarily of scientific value and no doubt of economic importance in countries where the barberry grows wild, it does not solve or even bring nearer solution the great problem of wheat rust in Canada. Yet it is a fact that the barberry occurs in Canada, and moreover, it is infected every year that we have been able to observe personally. In Manitoba we observed infections of barberries to such an extent that the shrubs appeared to be of a pronounced golden yellow colour from spore-cushions. It is, however, a fact deserving attention that in Manitoba and the other important grain growing provinces, Saskatchewan and Alberta, the barberry, while not entirely absent, is an apparently negligible factor, only very few bushes occurring in these regions. The question confronting the scientific advisors on such subjects, particu- larly under conditions similar to those prevailing in Canada— which are known to exist in India, Australia and elsewhere— is : If the barberry alone is res- ponsible for the perpetuation of grain rust, and if, without the barberry, grain rust, that is, stem rust, will go out of existence, would it not be the easiest matter in the world to save the immense losses from grain rust by the destruction of this comparatively worthless shrub T This is just the point which has been the subject of controversy all over the world and on which only very few reliable and conclusive data exist, if any. The complete eradication of barberries has not so far been carriod out in any country and not until this has been done and the effect of such action on grain rust has been recorded for at least a decade, can this question be regarded as satisfactorily answered. In the report of the Dominion Botanist of Canada for 1911, p. 239, the present status of our knowledge pf rusts was briefly summarized, and it was 13 letter in whieh he refera to thu statement, explaining that: ''Paccinia gramini. i. quite perceptibly di«appearing in Denmark year by year to the ume degree a. we get rid of the Berberii, and we are veiy well satisfied with the results of the Berberis Act." ehi.r!?t!!',?r°'^"''"°°/?!*'°"* important information of a more definite eharacter than any we had been able to secure previously. We thought it oommunicated with Dr. P. Kolpin Ravn of the Pathological Museum of Kopen nagen. He very courteously writes us : h«. hl^ '''"'' ^'"*'' ^u°" ^*"" *° """"^ ^*"'* "y P*"*""*! experience has been concerning the extermination of barberry bushes in this coun- ty. I have been able very often to observe early outbreaks of Pnccinia grammis on lye and oats; in all such cases-without any exception-we have been able to find some barberry bushes near by; and some years dSappeare""""" ^''^^^' *^^'"' "'"'^ ""t^reaks of rust had Several of the Local Advisers in Plant Culture carried on a system- atic fight against the barberry bushes, as required under the Act. And at present the early-and only dangerous-outbreaks of black rust are rarely reporteo. I may add that the farmers have practised for some recent years sowing spring grain earlier than before, which further helps in the fight against the rust. I think, therefore, that the present very slight infections by Puccinia graminis are the results of the two named factors taken together." «.»,•n^.^,.?^^'■^?' ^"^""T^ '° ^'''"'^'' "^ ^ '^°<'^° contributory factor to grain rust. In this attitude we are supported by practically every scientific observer on this continent and we, therefore, would strongly recommend the complete extermination of this shrub at any rate throughout the regions of the ^oZ^Z ^TT "^ '^'^°'''* *° ^"^ ^°^^°«- T'^^" "« other factors contnbutory to the seventy of grain rust over which we have no control- weather conditions for one-hut the .uestion of the barberry is one that might Zm h 7r°"'\" " ''"^ °* '^' ^"""P''^ precautionary measures tLt should be taken in the interest of tho grain-producing regions throughout the continent of America. One of the most ornamental shrubs of the genus Berberis is the very small leaved Japanese barberry (Berberis Thunbergii, D.C.) which is not attacked by rust and may be safely planted. POSMBLE PBBOAUnONB TO EBDUOB LOSSES FBOM OEAIN BUST No specific remedy is known at present that will control grain rust Seed treatment as practised successfully for smut diseases of grain has not IS •hown any redacUon of loues from nut. The reuon mnit be apparent to thoie who hare followed the deecription of the life hiitory aa given in the preceeding chaptera. Even though the aeed grain may exhibit winter aporet, theae cannot infect the wheat plant, and whether they are alive or have been kiUed by special treatment doea not much matter. The question as to whether the seed grain acU as a carrier for rust is one that has been .liscussed for iBtny yean ; while this possibility is not totally out of the question, it U certain that no treatment that has been tried gave any satisfactory results. The above statement should not convey a wrong idea, viz.— that it is useless to attempt the control of rust. HappUy, careful field studies, labora- tory inveatigationa and confirmation of resulta thus obtained by experiments under field condition*, have placed at our disposal the knowledge of a number of ''\ctor8 greatly encouraging the severity of the disease or rendering the crop more liable to attack or destruction. The careful elimination of suck factors, which are within the control of the farmer, will naturally securv beneficial results. Indeed, the last great epidemic in Canada once more confirmed the oorreetness of certain precautionary measures that can be suggested. On examining the area of wheat most seriously affected by the rust, it was found «iat single fields surrounded on aU sidea by fields badly smitten by the rust, stood out erect and affected to a considerably leaser degree than those close by. While the latter fields were not considered worth cutting because of the severe attack by mat, the others yielded often as high as 21 bushels per acre, some less and some even more. This was one of the most striking lessons of the rust epidemic and had all farmers known the reason and taken the necessary precautions, the losses from grain rust might have been very considerably reduced. In brief, the reasons for the escape from rust of some of the fields men- tioned were: Early sowing, which waa by far the most satisfactory; the use of early maturing varietiea which had in some caaes matured the grain before the fungus had done its destructive work; and sowing on high or sandy lands, or a combination of these three points together. From observations made in the Dominion of Canada, which are supported by the recommendations made in almost every wheat-growing country in the world, we would strongly urge all grain growers to follow the precautionary measures set forth below, when they can be assured that, even in the years of aerious epidemics, the losses fWm rust may be considerably reduced. Moreover it is wise to be prepared for the recurrence of rust epidemics at any time. 1. The ehdoe of land. The selection of good wheat land on the prairie is not generally a difficult matter or one which requires special care, since, generally speaking, the available land is very similar in nature and usually •oitable for wheat-growing. In some localities of rolling prairie, or prairie with sloughs and ravines, attention must be paid to the selection of wheat l*nd. It is moat important to avoid the use of wet land unless such is carefully •nd correctly drained. Wet land usually forms a cold bottom for wheat and 14 In muy e«M eumot b« work«>d very early. Thla delays aowing. be.idea. owiaf to cold tnd wet, the fermination of the grain ia delayed. Wet soiN •IM are generally Ueking in air; aeration of the aoil ia a great aid to the dOTelopment of a profnse root ayatem and a atrong, vigoroua plant in con- M^uenee. ♦1. *' .1?*^'!^ "^ Provided good land ia available, if the preparation of the •eed-bed ia not attended to with care and patience, the benefits aerived from .uitable land alone will be greatly reduced. The preparation of the teed bed should aim at that degree of mellowneu of texture in which the •eed may find most encouragement from aeration, warmth and moisture Therefore, any cultural practice by which an even, smooth surface is obtained is strongly recommended. 8. BoUtion. Continuous wheat cropping wastes soil fertility, increaxes the growth of weeds and is most injurious to the vigorous growth of wheat Slow growth delays maturity and late maturity is disastrous in years of rust and also exposes the crop to frost injury. i, Wowia. Weeds impoverish soil besides using up soil moisture that should be retained for the wheat. Thorough weed eradication is essential to the success of any crop. It u useless to expect a full crop of wheat from a weedy field, and besides, the yield of sound grain is contaminated by weed seeds. 8. Seed-Orain. A matter of much greater importance than the variety of wheat most suitable in any one particular region is that the seed grain be composed of the heaviest, plumpest kernels possible. All seed must be treated for smut every year, but this treatment is well-known to have no effect on the grain rust. In yearn following severe rust epidemics or where the grain was much injured by frost it is necessary to exercise particular precautions to remove all shrivelled and light seeds. To sow grain containing a larjre percentage of these inferior seeds, is really to invite loss since the weak plants resulting from such seed show an increased predisposition towards disease^ Needless to say, old seed grain of low germination or frosted gram should not be sown for the same reasons. The seed to use should be of strong and even germination. A small sample of wheat is easily tested by the farmer himself. For this purpose, use two Hup plates and place a small number of grains between folds of moist blotting paper or pieces of uncoloured flannel and cover same with another plate. If this primitive germinating apparatus is kept in a warm place, the seeds will have sprouted in four or five days. A sample showing 70 and more seeds sprouted in this time, out of 100 is considered to be of strong germination. To sprout all seeds may take a week or more. A sample showing, after four or five days, only a germination of 20 or less, cannot be considered of strong germination, although all grain may eventually have sprouted after a week or so. The more rapid the energy of the grain, the more suited it is for sowing and producing even, strong plants ti Matif Mvwtag. Etlj aowing of the Mcd ia on* of tht moat important taeton to praT«ot Mriona loaae* from niit. The crop often eeeapei nut injnrjr altogether, but when attaeked, the development of the kernel will hare io advanced that the loai will not be lerioui. 7. larly VariatlM. An early maturing variety of equal value and yield to the Red Fife and Marquis wheat ia yet to be diaeovered. The uae of early varietiea ia recommended, if they are aatiafactory aa regarda yield and quality. Prelude wheat ripening aome 10 — 15 daya earlier than Marquia, haa almoat en- tirely eacaped aerioua mat injury, but cannot be generally recommended where Marquia and Bed Fife can be grown and yet in 1916 it aaved many farmera from incurring conaiderably greater loasei. Marquia wheat matnrea earlier than Red Fife and from the atandpoint of rust-eacaping ia much to be preferred. It yielded much better laat year than Red Fife on account of ita more early maturity, thua in a meaaure eacaping the mat. It will b« aeen that earlier maturity may save the crop, therefore early aowing and the uae of early varieties or any cultural operation hastening maturity, are moat atrongly recommended. 8. Tba Barbarry. Thia ahmb haa no place near grain fielda or in grain- growing regiona, and ahould, therefore, be exterminated, aince it is just as much a contributory factor to grain rust, as late sowing and others over which we can exercise control.