NEWS for North Dakotans
Agriculture Communication, North Dakota
State University
7 Morrill Hall, Fargo, ND 58105-5665
September 24, 1998
Hortiscope
Ron Smith, Extension Horticulturist
North Dakota State University
(I'd like to request that those of you who send me letters through the U.S. Postal Service remember to include your complete mailing address; otherwise, I have no way to personally answer your questions or send you NDSU Extension Service publications. Thanks!)
Q: Can you tell me what causes scabby potatoes and what to do to solve the problem? (Lehr, N.D.)
A: This is a soilborne disease organism that develops from perpetual cropping of potatoes. I suggest a three-year rotation, and planting with resistant cultivars like Russet Norkotah, Red Pontiac, Norland or Superior.
Q: I have had this tree for four years. This year it bloomed and now has these little pears on it. Is this an ornamental or a pear tree? (Sykeston, N.D.)
A: It is both—an ornamental pear tree—Usurrion pear. Enjoy!
Q: I am having trouble with my peppers getting a soft spot on one side. It looks kind of like blossom end rot that sometimes is seen on tomatoes. Is this possible and what should I do to stop this problem? (Hannaford, N.D.)
A: Peppers do indeed get a blossom-end-rot malady like tomatoes. Basically, the same treatment: mulching at time of planting, steady water supply, and cultivar selections that are not prone to the problem.
Q: Can you tell me whether the enclosed berries are edible? (New Rockford, N.D.)
A: Your tree is a crabapple, and the fruit makes excellent jellies and applesauce.
Q: I have three cyclamen and two have quit blooming. I am wondering how to redo them. (Devils Lake, N.D.)
A: You are a brave person to tackle the perpetual care of a cyclamen!
After blooming, they need a drying period in a cool location (50 to 60 F). This should go on for about 90 days. Then begin watering and fertilizing once again. Keep the plants in bright, but indirect, light.
Other than this, I don't know what else to tell you. You are attempting something I would never undertake!
Q: Can you tell me what is causing the apples to fall off of our tree too early? The core of the apple is outlined with red streaks, which gradually spread through the apple causing it to lose its crispness. Also, will it spread to the other apple trees we have? (Conde, S.D.)
A: It sounds like you are having a problem with the great tunneler of apples, the apple maggot. Good sanitation, meaning fallen apple cleanup this autumn, will help control this pest.
Also, spray the tree twice: once in early spring to sanitize it before leaves open, with lime-sulfur, and again at flower petal drop to control the insect, with Sevin insecticide.
Q: We are planning a flower garden for our yard and would like to include native flowers and plants. Can you please provide us with a list of appropriate flowers and plants? (Bismarck, N.D.)
A: Enclosed is a flower NDSU Extension publication that Barb Laschkewitsch and I put together which should be helpful to you: "Annual and Perennial Flower Selections for North Dakota" (H322).
Q: Can you tell me what kind of chemical I should use to get rid of this weed I have enclosed? (Fargo, N.D.)
A: You have an excellent crop of ground ivy or creeping charlie (Glechoma hederacea). This is a tough perennial that will require repeat applications of a product like Trimecand. Now is a good time to start.
Q: Can you tell me why my crabapple tree appears to be dying? (York, N.D.)
A: The tree is showing symptoms of apple scab, an especially bad fungal disease this year because of the humid, rainy weather we experienced at the start of the season.
This can be controlled with one of the broad-spectrum fungicides in the spring when the buds are showing green at the tip, then again after full leaf expansion. Materials like Captan, Ferbam, or Mancozeb will do the task.
Q: Enclosed is a branch from my May Day tree. Can you tell me what disease or infestation is affecting it and what I can do to stop it? I have been trying to prune many of the branches. Also, can you identify this vine that is growing among some wild grapes? (Walhalla, N.D.)
A: Your May Day tree is loaded with cankers—fungal diseases which eventually kill off branches, as you have discovered. Sanitation, such as what you are doing, removing the infected limbs is the best approach. You may also try spraying with Bordeaux mixture to help control it.
I am not sure of your vine. It smells like a member of the Nightshade family, but I cannot get it to key out for me. To be on the safe side, don't eat the fruit!
Q: Can you tell me what is wrong with my tree? I think it is a cottonwood. I also would like to know why my Larime strawberries are not bearing fruit? (Binford, N.D.)
A: Poplars or cottonwoods are prone to a plethora of diseases. In your case, the problem is Septoria leaf spot, a fungus brought on by rainsplash, humid weather, and poor air circulation.
Best control is sanitation—removal of all fallen leaves this autumn. You may want to try a fungicide next spring after the leaves open to protect the tree. Something like Daconil, Maneb, or Mancozeb would be good selections.
Your Larime strawberries should have set fruit by now. Perhaps you've fertilized too much or the soil is too high in nutrients. If they don't fruit next year, replace them (assuming you want the fruit and not the ground cover)!
Q: Is there something we can spray on our ash tree to slow down the production of seeds? They make a mess in our yard year round. (Drake, N.D.)
A: In the "old days" there was, but not any more. Sorry!
The seedlings are easily controlled with a dilute solution of any broad-leaved herbicide. Just be careful where the spray is directed.
Also, simple shallow cultivation will take care of the emerging seedlings—stopping them dead in their spot.
Q: Can you tell me what is wrong with my silver maple tree? (Napoleon, N.D.)
A: Your maple is suffering from a number of maladies: iron chlorosis (severe), tar spot, anthracnose and mite damage. At this stage, I'm afraid there isn't much you can do. You may want to attempt the following: core aeration starting at the dripline (canopy edge) and going concentrically out 10 to 15 inches, spreading of sulfur over area aerated, and watering in completely. Apply sulfur at a rate of 35 pounds per 1,000 square feet. This will help lower the pH and may improve the health of the tree by making more true elements (like iron) available.
Q: Can you tell me where I can purchase some Israeli tomato seeds. It says in this ad that they are powerful in fighting cancer, and I would like to try them. (Rugby, N.D.)
A: Sorry I don't know where you can get the Israeli lycopene-enriched tomato. But, shame on whoever wrote the advertisement promotion! "...Farmers in Israel have come up with a hybrid tomato that contains between 4 and 10 times the lycopene content of regular varieties!" Now, just what is a "regular variety"? The ones that all the other seed companies have hybridized? I don't think they'd agree!
Be confident that all ripe, fresh tomatoes are rich in lycopene and will have the same anti-cancer benefits of the Israeli tomatoes. I would simply like to try them to see if they taste any better!
As a member of the Garden Writer's Association of America, I should be among the first to know when (or if) this product becomes available. When I do, I'll let everyone know through this column.
Q: Can you identify the leaves enclosed from this tree (bush) for me? It turns beautiful red at the first frost. (New Delhi, India)
A: The tree is the beautiful Amur maple—Acer giunala. It ranges from hardiness zone 2 (southern Canada) to zone 8 (central TX, GA, AL), although it does better in the more northern zones.
Q: Can you let me know how to control the enclosed "weed"? It's growing like crazy in my flower bed and I don't want it to harm the plants and shrubs that are growing there. (Ashley, N.D.)
A: Why, you have a virulent, vile violet that needs to be vilified until it is vanquished! You may begin doing that with Trimec or Confront, whichever you can obtain without too much trouble. Expect to do repeat applications, as it is very persistent!
Q: We have an 80-year-old box elder tree that has a large crack in it. We cut away the damaged wood, but we are wondering if there is something we can paint on the trunk to preserve the rest of the tree? (Tappen, N.D.)
A: Basically, you don't need to do a thing to the cut surface. If the tree is healthy, the wound will heal naturally; if the tree is unhealthy, there is nothing you can spray on it that will facilitate healing.
I suggest you have the tree checked by a forester for internal soundness. Although the photo shows sound wood where the cut was made, the old box elder is close to the end of its typical lifespan and may have some internal rot that is not evident from the outside. Such a condition could pose a danger to your family.
Q: Can you please tell me how to control night crawlers? They are ruining my lawn and I want to get rid of them. (Napoleon, N.D.)
A: Use Sevin at the label rate for grub control. Be sure to water in well, with about 1/3 inch to ½ inch of irrigation. Repeat again in the spring when they are again active. These two treatments should give about 70 percent control.
Q: Can you please tell me what these knobs are that are growing on our Northwest poplar, and what we can do to stop the spread of it? (Garrison, N.D.)
A: Your poplar has a stem gall which is caused by various creatures: aphids, mites, midges, flies etc. The damage is local, and other than premature leaf drop or stem breakage on affected branches is usually not a problem to the survival of the tree.
In your particular case, the gall is caused by the feeding activities of an as-yet-undescribed species of eviophyid mite. If you can, prune out affected branches prior to leaf-out next spring.
Q: Can you please tell me what disease is attacking my Alpine currant? (Richville, M.N.)
A: The currant has symptoms of anthracnose, a fungal disease of the foliage mostly, that gets started in early spring. To control, follow good sanitation procedures by cleaning up all leaves this fall. Next spring after leaves have unfolded spray with Bordeaux mixture. Repeat in three weeks. Be sure to cover both leaf surfaces, using a good spreader.
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Source: Ron Smith (701) 231-8161 ronsmith@ndsuext.nodak.edu
Editor: Dean Hulse (701) 231-6136