Truck Crop and Garden Insects.
AN EXERCISE LED BY PROF. WM. MOORE, ENTOMOLOGICAL DEPARTMENT, UNIVERSITY FARM, ST. PAUL.
There is one insect that probably all those who are in the market garden business are very much interested in, and that is the cabbage maggot. As you all know, in the spring of the year, after cabbages are put out, frequently you will find the cabbages slowly dying, one dying one day and two or three the next day, and so on until sometimes fifty per cent or more of the cabbages die. At first it is not exactly apparent what is killing the cabbages, but when one is pulled up it will be noticed that a little maggot is working in the root of the cabbage. This insect is commonly known as the cabbage maggot.
For a number of years work has been carried on with the cabbage maggot, and all sorts of treatments have been tried, many without any great success. The unfortunate part is that usually the market gardener don't take much thought of this maggot until it is actually doing the injury, and at that time they are mighty difficult to handle.
There have been several different treatments advised, one of which is fresh hellebore, about two ounces steeped in a quart of boiling water and then diluted to a gallon and poured upon the base of the plant. It will destroy the maggots, but hellebore is very expensive and, as probably most of you know, there isn't a great amount of profit in cabbage; so any treatment will have to be a cheap treatment, or you will use up your profit.
During the last two years I have been working along a line which is entirely different from the treatment of the maggot, and that is based upon the fact that the fly which lays the egg which produces the maggot in the cabbage comes out early in the spring and flies about the field for probably a week or ten days or two weeks before it lays its eggs, and during that period it eats any sweet material which happens to be on hand. With this as a basis we thought we might be able to poison the flies and thus prevent injury from the maggots, and we have tried several different spray mixtures along that line. One mixture which we use is a mixture which is normally used against the fruit flies which are oftentimes injurious to fruit, particularly in the east and in tropical countries. This contains three ounces of arsenate of lead, two and half pounds of brown sugar and four gallons of water. The idea is to spray this in the field, spraying it on the plants as soon as the plants are put out in the field. We have more or less definite dates for the appearance of the flies in the field and for their disappearance again. But, as you know, the season varies, and the result is somewhat uncertain. So probably the best method is to base it upon the time you plant out your cabbage. In the early seasons you will plant your cabbages early, and in the late seasons later. So plant out your cabbage and then spray them every week until the 10th of May.
You should spray them, not to cover the leaves with the poison, but merely sufficient so that there are a few drops of this poisoned material on the leaves so that the flies can eat it. Flies will come there and feed upon this mixture and die.
It is rather peculiar that we started work here about the same time on the cabbage maggot that they started work on the onion maggot along similar lines in Wisconsin. I don't think that either knew that the other was working towards that end. They used a different mixture, one-fifth ounce of sodium arsenite, one-half pint of New Orleans molasses and one gallon of water. This was sprayed over the onions and was very successful in controlling the onion maggot.
I tried their mixture this last year. They published some of their results last year, so it gave me an opportunity to watch their mixture in comparison with the lead arsenate. They claimed the lead arsenate did not act as quickly as the sodium arsenite. That is true, but when you have a ten-day period to kill the fly it don't make much difference whether it dies in ten hours or twenty-four. The flies are not doing any injury. If you take the lead arsenate and sugar and water and put it in a jar, the arsenate always sinks to the bottom, and if you were to test it that way, the fly would feed on the top and you might not get a quick result. But if you spray it on, the lead arsenate will kill as quickly as the sodium arsenite.
There is an objection to the use of arsenite in that sodium arsenite is a soluble poison and will burn the leaves of the cabbage. Of course, that is not particularly serious as those are the first leaves the cabbages have and the cabbage soon gets over any slight injury, but many truck gardeners probably would object to that. In the onion you have a different shaped leaf, and the injury is not so apparent. Last summer I found that New Orleans molasses would give you a little bit better result than the sugar, and it is cheaper. The objection to the New Orleans molasses is the sticky nature of the material in handling.
I might mention in regard to opening cans of New Orleans molasses. If you never opened one and try this treatment, be careful about opening the can. The lid is pushed down tight and under warm conditions, or if the molasses has been in a warm room there is a certain amount of fermentation and gas under pressure, and if you pry it open quickly you find the lid flies up in the air and you will probably be smeared over with molasses.
I employed my spray, that is, one ounce of lead arsenate, one-half pint of New Orleans molasses and one gallon of water last season. The check plots had cabbages attacked by the maggots, probably 10 or 15 per cent of the plants dying from the attack. Last year was a very good season, that is, many of the plants seriously attacked put out roots again, and those were able to grow again in the sprayed plots. The infestation of the sprayed plots was probably about 30 to 40 per cent. of the plants, but they only contained probably one maggot each, which is very slight and not sufficient to do any damage.
There is one market gardener whose cabbage patch we sprayed, I think, only a part of two rows, and we thought we would leave the rest of his patch as a control. Apparently the amount of material we put on there was sufficient to attract the flies from the whole field. Not a single cabbage died, and he was pleased with the result of the spray.
Mr. Miller: What do you do for root aphis?
Mr. Moore: Root aphis can very easily be controlled with tobacco extract. It is put upon the root of any plant that is affected, a tablespoonful to a gallon of water. There are a number of different tobacco extracts on the market. Some of them contain 15 per cent. of nicotine, some contain 20, some 25 and some 40, and I think there is one brand that contains 45 per cent. You will find that the brands that contain the most nicotine are the most expensive, but in proportion you use less material. Thus 20 per cent. tobacco extract would take two tablespoonfuls to the gallon, while 40 per cent. would take only one. It is the nicotine which is the working portion of it.
Mr. Miller: Then you can use the black leaf forty?
Mr. Moore: It is very good, it is 40 per cent. nicotine. There is another product put out by the same company, a black leaf, only 15 or 20 per cent. This is cheaper, but you have to use more of it. If anything probably the more expensive would be the cheaper in the long run.
Mr. Wintersteen: The maggots that attack the radishes and turnips are the same as the cabbage maggot?
Mr. Moore: Yes, sir.
Mr. Wintersteen: Why is it I have no trouble with the cabbages, and yet I can raise no radishes or turnips in the same ground?
Mr. Moore: The radishes and turnips are attacked and the cabbages are not?
Mr. Wintersteen: Yes, sir.
Mr. Moore: Which do you raise, early cabbages?
Mr. Wintersteen: Yes, sir.
Mr. Moore: What variety do you raise?
Mr. Wintersteen: The Wakefield, generally.
Mr. Moore: Some varieties of cabbages are not nearly so severely attacked as others. I think of the two that they would prefer radishes probably. Growing them side by side you find they infest the radishes. That was my experience last year. I grew the first generation of cabbages, and the second generation I took over into the radishes because I wanted to treat them there.
Mr. Rasmussen: Did you say the same fly attacks the onion and the cabbage?
Mr. Moore: The onion has two different flies, one which is black in color, with light colored bands across the wings, and that one passes the winter as a larva in the old onions left in the field. It is an injurious practice to leave old onions there to breed these maggots. If they were taken out and destroyed you could do away with that one. The cabbage fly is different. When you use the spray it would probably be all right to use the sodium arsenite for the onion and the lead arsenate for the cabbage. The type of leaf is entirely different, and on the cabbage you are apt to burn them with the sodium arsenite while the lead arsenate will give you practically the same result.
Mr. Goudy: The cabbage butterfly, does that come from the same maggot?
Mr. Moore: No; this maggot is on the root, the cabbage butterfly lays its eggs on the leaf. You get the cabbage worm from the cabbage butterfly.
Mr. Goudy: What do you do for that?
Mr. Moore: Paris green is used to a great extent, but many people have a horror of using Paris green. Last year, I think it was, I was called up on the phone by some one and I advised him to use Paris green. He said that he was afraid it might poison everybody. I explained to him there was no danger from it, as you know the cabbage leaves grow from the inside, not from the outside, and the spray would be on the outside leaves. Besides that, we usually spray early for the cabbage worm while the heads come on later.
Mr. Goudy: Did you ever try capsicum, sprinkling that on the heads?
Mr. Moore: No, sir.
Mr. Goudy: I saved my cabbages one year by using that.
Mr. Moore: Some people claim salt is good. One of the students mentioned it to me. One applied it by putting a spoonful around over the head, another dissolved a tablespoonful in about ten quarts of water and sprayed it on. Salt is rather injurious to vegetation as a rule. Of course, they only put it on the leaves, and the cabbage is a hardy plant. Air slaked lime is also good, but would have to be applied several times. With the arsenate you apply it once and kill all the brood.
Mr. Ludlow: We took them all off of mine one year by using boiling hot water.
Mr. Moore: Yes, sir; water is very good. The objection is, on a large scale it is not feasible.
Mr. Miller: Slug shot is very good.
Mr. Moore: Yes, sir; it doesn't contain very much poison, but it is sufficient to kill the cabbage worm.
Mr. Cadoo: I used just simply wood ashes.
Mr. Moore: The cabbage worm is one that is very easy to handle.
A Member: I have always used salt. I think it makes a more firm and solid head, that is my theory, I don't know whether I am right or not. I have been doing that for years.
Mr. Moore: I don't know. I never heard of the treatment with salt until two or three days ago when several students mentioned that they used salt. Some people won't use Paris green. There was one case a man said his wife wouldn't let him do it even if she knew it wasn't poison; she didn't like the idea of Paris green on cabbage.
Mr. Ingersoll: Is there anything you can suggest to control the yellows in asters?
Mr. Moore: The yellows in asters has been a problem which has been very amusing there at the farm. A man sends in an aster to the entomological department, we examine it and can't find anything that belongs to our department, and we send it to the plant pathological department, and they send it back to us. Last year we made a point in every case of yellows in asters to send some one to investigate and find out what was going on to produce it. In some cases it seemed to be a fungous disease. One case I know turned out to be a fungous disease, the very next one was due to plant lice on the roots of the asters. In that case I don't think you get quite the distinct yellows of the asters, but rather the plants wilt and become weak and finally die. That can very easily be controlled with tobacco extract, pouring it upon the buds of the plants. We do not know definitely about the yellows. We think it is more or less of a physiological disease of the plant, not due to an insect. This last year we have not found any what we would call the true yellows. There is an insect that produces similar trouble on other plants, a plant bug, which is hard to secure because it flies away. That is the reason we have been sending out to see exactly what is going on in the field, and we didn't see any evidence of their work this year. Another thing, it seems to be a year in which the asters did fairly well, and there was very little yellows.
Mr. Ingersoll: You think that irregular watering might make any difference or very solid rooting?
Mr. Moore: It might do something of the sort. The most we heard of the yellows was the year before last, and we were held up at the time with other work and could not investigate properly. Any one here that has yellows in asters next year, we would be very glad to hear from him and send some one out to find the cause. It wouldn't surprise me that it was something in the treatment of the aster.
Mr. Cadoo: Do angleworms hurt house plants?
Mr. Moore: Not as a rule. They do eat a small amount of vegetation, but ordinarily in a house plant, if you have, say, a worm in a pot, I think it is rather beneficial than injurious, because it keeps the soil stirred up.
Mr. Rasmussen: What is the spray for the cabbage and onion maggot?
Mr. Moore: Unfortunately I am a very poor person to remember figures, and I carry this around with me. One spray is three ounces of lead arsenate, two and a half pounds of brown sugar to four gallons of water, but we found that probably a little better spray was to use the New Orleans molasses instead of the sugar and the formula is: One ounce of lead arsenate, one-half pint of New Orleans molasses and one gallon of water. The spray that was used for the onion maggot and was devised over in Wisconsin is: One-fifth ounce of sodium arsenite, one-half pint of New Orleans molasses and one gallon of water.
Mr. Rasmussen: The Wisconsin spray is what I used to spray my place several years, and I was wondering if it was the same.
Mr. Moore: It was peculiar that they started to work on the onion maggot in Wisconsin at the same time we started on the cabbage maggot here.
Mr. Rasmussen: We have controlled the onion maggots almost entirely, but the cabbage maggots are very difficult.
Mr. Moore: In our control plots it controlled it very well. Our plants were infested only with a few maggots, but not sufficient to do any injury.
The Wealthy Apple.
F. H. BALLOU.
(THE OPINION OF AN OHIO APPLE GROWER—FROM A BULLETIN ISSUED BY OHIO STATE HORTICULTURAL SOCIETY.)
The value of a variety of apple commercially usually decides its place in the estimation of growers. Naturally the later maturing, longer keeping or winter varieties are generally accorded this preference. Orchardists in the southern part of Ohio doubtless would elect Rome Beauty queen of money makers, were the question put to a vote. Apple producers of northern Ohio or western New York would as surely vote for Baldwin. But what variety would you—Mr. Lover-of-apples-and-apple products—vote for and plant if but a single variety and space for but a single tree were available? After twenty years observation and enjoyment of apple precocity, apple dependability and all-around apple excellence throughout a long season, the writer continues annually to cast his ballot for Wealthy.
Mr. Rolla Sfubbs, of Bederwood, Lake Minnetonka, under his favorite tree, the Wealthy.
True the Wealthy has its faults—so have all the other varieties of apples of individual choice—and so have we—the growers; but for early fruitage, prolificacy, excellence for culinary use, extended period of usefulness, richness and delicacy of flavor when ripened in a cool cellar and good keeping qualities when under proper conditions it is placed in cold storage, there are few if any varieties other than this that combine so many splendid and desirable characteristics. From mid-July to mid-September of the present year we have been using Wealthy for culinary purposes with steadily increasing enjoyment as their quality has gradually become finer and finer. At this writing, September 18, we have in the cellar attractively colored, well ripened, pink-and-white-fleshed Wealthy delightful for dessert use; and there are yet Wealthy—firm and crisp—on the trees for later autumn use if kept in the cellar, or early winter and holiday use if placed in cold storage.
If we could have but one apple tree that tree would be a Wealthy. This statement is made with full knowledge and appreciation of the many other excellent varieties of various seasons, including Grimes, Jonathan, Stayman and Delicious.