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carried by air currents to certain distances in the air, in order to get some line on the distances.

As a check on effectiveness of rust control and an aid to directing control activities, information is obtained concerning movement in air currents of rust spores from both rusted grains and barberries. During the early and late spring, Weather Bureau observers at some twenty selected stations in the Mississippi Valley and at other strategic points daily expose spore traps on roofs in the course of their regular work. These spore collections have been supplemented by occasional upper air collections made in the lower Mississippi Valley from Army airplanes on short hops from local flying fields, at Great Lakes, Ill., in Navy training seaplanes, and along the Atlantic seaboard on routine training flights by Navy training ships and on Coast Guard airplanes. Only five such flights were made in the past season. Similar work is being done in Russia, Germany, and Canada.

Mr. BUCHANAN. You mean you have an instrument on the airplane that will catch the currents of the air and enable you to ascertain whether there are any spores in it?

Doctor TAYLOR. Yes, at different elevations and at different seasons when the fungi are shedding spores.

Mr. BUCHANAN. So far, what is your determination?

Doctor KELLERMAN. They do move for considerable distances in the upper air at certain times.

Mr. BUCHANAN. You know, Doctor, what one man might call & considerable distance another man might not so consider it.

Doctor KELLERMAN. Of course, that is very difficult to ascertain. It is impossible to ascertain it with any exactness because you can not tell where that particular bunch of spores started from, but you do find them moving.

Mr. BUCHANAN. Well, if you catch them so many miles from any known infestation of barberry bush, why you would know then, would you not?

Doctor KELLERMAN. Well, it would be a fair guess at it.

The consolidated information, the consolidated evidence, is pretty largely indicative that the serious infestation and the serious spread of the disease, when the weather conditions are favorable for its epidemic spread, is limited to a relatively few miles, that is to 15 or 20 miles, and that as you near the barberry, that is the wheat fields nearest the barberry bushes are the worst damaged by the disease. Of course, there it was a question of the number of spores. The nearer the bushes you get a very much larger number of spores resting upon an individual wheat plant in a given field.

Mr. BUCHANAN. Well, if the 15 or 20 mile carry of it, going through the air, is substantiated, of course, then there would be no danger of it coming up from the South, from Texas for instance.

Doctor KELLERMAN. Theoretically, there is some risk in certain years from spores carried by the wind from the Southern States where the red or repeating stage lives over the winter. Actually, the evidence that we have does not indicate that that is an important factor of early infection and spread in the average year.

Mr. Buchanan. If it should be developed that through the air currents it would come up from the South then this campaign is of no use.

Doctor KELLERMAN. Not necessarily. Studies made since the beginning of the barberry-eradication campaign in 1918 have shown that in the Northern States the early development of stem rust and the most damaging epidemics of the disease are associated with the remaining common barberry bushes. However, during certain seasons when an abundance of rust is present in the South and wind, moisture, and temperature conditions favor the northward movement of spores, stem rust may develop in the spring-wheat area as the result of wind-blown inoculum. Rust from this source usually appears later in the growing season and is characterized by a scattered distribution over extensive areas. Unless crops are abnormally slow maturing, serious rust damage ordinarily does not occur.

Mr. BUCHANAN. On the other hand, if it did come, it would be apt to come in small quantities and there being no barberry bushes up here for a host why, a reinfection next year would depend upon another air current to bring some more of the fungus up.

Doctor KELLERMAN. The fungus spores.



Mr. BUCHANAN. I am asking this question generally because I just thought of it. I just met a member of the economy committee. Of course it is a very critical committee, and he claimed, which I denied, that the Bureau of Plant Industry was dealing with the eradication or control of insects and that of course that was duplication between it and the Bureau of Entomology. I contradicted it and told him that the trouble in his mind was that he had not drawn a distinction between damages done by fungus growth and fungus infection and insects. Is that correct?

Doctor TAYLOR. You are right.

Mr. BUCHANAN. You do not undertake the eradication or control of any insects in your bureau?

Doctor TAYLOR. No; the only relationship that our work has to insect studies is in cases where insects are suspected of being the carriers of a particular fungus or bacterial disease, in which cases there is needed a determination of the relationship of the insects to the fungus in its spread, and in such cases we arrange a cooperative attack upon it with the Bureau of Entomology, so that you can assure any one that there is no duplication between the work of the Bureau of Plant Industry and the Bureau of Entomology.



Mr. Hart. How much of this appropriation of $180,722 goes for the employment of labor in the destruction of the barberry bushes?

Doctor KELLERMAN. There are 67 laborers on the roll and 79 temporary appointees. That represents a considerable increase in labor over the previous year and that same change will probably occur in somewhat the same percentage for next year. That is assuming the same appropriation would be still large enough in proportion for the labor expenditure and the reduction of the number of agents employed.

Mr. Hart. Are these temporary?

Doctor KELLERMAN. All of the labor is carried as temporary. All of this work is done during the spring and summer season. There is a maximum period of work on that ranging from about two to five months, depending upon weather conditions.

Mr. Hart. What proportion of the $180,722 is paid out for this labor for actual eradication and how much for scientific or regulartrained men?

Doctor TAYLOR. The supervising personnel?
Mr. Hart. Yes, the ones you carry the year around.

Doctor KELLERMAN. I think the figures here will show that. On page 112 you will find the detailed figures. Counting in both clerical and technical work the total expenditure shown there is $32,048, and with the salaries and wages of temporary employees in the field it is $93,046.

Mr. Hart. With the decrease in wages of common labor we ought to be able to maintain the activities even with the decreased appropriation. Do you not think so?

Doctor KELLERMAN. Perhaps, although the wage scale has been reduced during the current year. Whether it will go much lower than it has been during the current year we can not very well predict at this time.

Mr. JUMP. There has been a big drop in this item. In 1932 they had $93,000 for the temporary employees and, with the cut in appropriations it went down to $33,000 for this year and it is allocated $29,000 for next year. That is a reduction of more than 60 per cent.


Mr. BUCHANAN. Well, I guess you are destroying the bushes & little faster than they are increasing.

Doctor KELLERMAN. Very decidedly. I think it is fair to say, Mr. Buchanan, that the most troublesome phase of the work is over. The detailed visiting from farm to farm with detailed location of bushes on farms has just about gone into history. I think we can take care of that work from now on through the cooperation of the schools, the 4-H clubs, and the extension agencies. That is not going to be of material expense except in these areas where we find local epidemics. That is our method now of determining where we need to put some special field work.

If there is an epidemic, for example, in one of the northern counties of North Dakota, where there was a little epidemic this year that seemed to be just around that county, next year we will have men around that county to make a more thorough survey.

That is just about as good an indication as a thermometer is to a physician, that the bushes are being overlooked in that region somewhere, so some men will be sent in to work with the local people but, generally speaking, the farm areas can be handled by cooperative work with the schools and other agencies of the State.

Mr. BUCHANAN. And, you can concentrate on the rough lands? Doctor KELLERMAN. Yes, sir.


Mr. BUCHANAN. One other question on this. I assume that the infection or the damage done to wheat is more marked and to a greater extent where there are barberry bushes in the field or along near the field.

Doctor KELLERMAN. That is true.

Mr. BUCHANAN. So that, if you destroyed them in the wheat fields, and surrounding the wheat fields, the appropriation from your standpoint has been justified in decreasing the amount of damage even though they continue to exist in the wild or upper area. Doctor KELLERMAN. I think that is true.

Mr. BUCHANAN. If your figures are correct, you have made a marked, a real showing on the amount of damage that has been done to the wheat, judging from these 5-year periods marked out on that map.

Doctor KELLERMAN. Yes, I think there can be not much doubt on

that now.

Mr. BUCHANAN. And as long as we keep the barberry bush in the status it now occupies we would not expect another high peak damage like we had in 1916?

Doctor KELLERMAN. No, I do not think we would ever get such a high peak, but if we happened to have a succession of weather conditions that were just exactly right for rust, and starting in with the rough land in Wisconsin, for example, and moving gradually westward through the big grain areas, we could have.

Mr. BUCHANAN. You could have air currents at the right time and everything and have a considerable increase in the amount of damage done in one year, or more than one year as far as that is concerned, but still, with the same conditions existing that year that existed in 1916, you would probably have less damage than you had in 1916. Doctor KELLERMAN. If we can keep the farms and nearby regions clear we are never likely to have such a bad time as we had in 1916.


Mr. Hart. I can give you an illustration of another plant disease which worked a good deal the same as this and yet nothing was done to eradicate it and climatic conditions eradicated it. Take the anthracnose on beans. I forget the date, but I think it was around 1908 or 1907, around there, up in Michigan, in which certain sections of the state had a damage from very little of it, under 5 per cent of the actual seed bean and running up to as high as 50 per cent of the entire seed plant, and we got all excited over it and shipped beans all over to get disease resistant beans, and did a lot of things of that description, and then along came a period of dry years, during the succulent stage of the pod, and we have not had any attack since that time, notwithstanding we changed seed in some instances. Doctor KELLERMAN. You have been changing seed, too. Mr. Hart. Yes, we have. Doctor KELLERMAN. And, without your getting seed from the west, which comes from a region where it is dry enough so that there is no trouble with anthracnose, that is if you had been using your own seed steadily in that area up there you would hot have gotten out of the woods.

Mr. Hart. I am not so sure about that, Doctor. I will tell you what I did. I took the infected seed, that is a bean with spots on it and planted that and got a very good crop.

Doctor KELLERMAN. You may in a dry year and of course in the last years we have had some pretty dry years.

Mr. Hart. This, of course, goes back quite a period and yet thousands of farmers there did not change their seeds. Of course, there was a lot of new seed I admit came in, still I think we would have come out of the woods anyhow. I think the other probably helped.

Doctor Taylor. Was not the difference between the bean anthracnose and the wheat rust this, Mr. Hart, that with the bean anthracnose you are dealing with an annual crop which had no intermediate host upon which the anthracnose could winter over and get its start in the spring, as we have with the rust in the barberry. If you had dry weather, what anthracnose was left was on the straw and the rubbish that was scattered around, or on the seed that was planted, and if the seasonal conditions, the climatic conditions of the season, were adverse to anthracnose that year, it would not get a start at all.

Mr. Hart. That is right, we spread it by cultivation.

Doctor TAYLOR. Yes. Now, with barberry, on the other hand, if you have got your infection on the barberry every spring, regardless of how the weather is, it is just ready to leap forward if the weather comes right. You have to carry over an infection which, while there is some carry-over with anthracnose on the rubbish, it is not exactly parallel

It is primarily carried in the rubbish which is always more or less there on the ground.

You get somewhat the same situation with a disease like the fungus brown rot on peaches and plums of which there is always enough carried along on the rotten peaches of the year before, which drop to the ground, so that there is enough there for a start but if the weather does not come showery and warm in the early season's growth your fungus does not get the start which destroys the crop.

Mr. BUCHANAN. Your point is that when you have abundant barberry bushes, they always will do material damage.

Doctor TAYLOR. They are ready with a chance for the fungus to jump when conditions are favorable.

Adverting to your question, Mr. Buchanan, with respect to whether the disease would remain in check in so far as its economic effect upon the wheat crop is concerned.

Mr. BUCHANAN. I mean a degree of check.

Doctor TAYLOR. Yes; we must not forget that the birds are working right along and if we have an acreage of rough land with barberries the seeds are being carried and you are restocking again.

Mr. BUCHANAN. That involves a follow-up with ultimate extermination in your rough lands if possible.


Doctor Taylor. That is the thing which we feel we should do.

In this appropriation, as in previous years, it is specified that $75,000 of this amount shall not be expended until cooperating agencies have provided that much, which they have done this year, notwithstanding the heavy reduction in the Federal appropriation for this

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