NEWS for North Dakotans
Agriculture Communication, North Dakota
State University
7 Morrill Hall, Fargo, ND 58105-5665
October 8, 1998
Hortiscope
Ron Smith, Extension Horticulturist
North Dakota State University
Q: Can you tell me what kind of beetle this is? I found it when I was cleaning up the fallen apples in my yard. It is a small gray and red beetle with black spots. Are they harmful and what should I do to get rid of them? (Aberdeen, S.D.)
A: You had one of many species ladybird beetles. These unique insects are beneficial to us in both stages of their lives—the larval and adult. In the larval stage, it is a voracious feeder on aphids, and the adult continues that habit, expanding the eating palate to other plant-destructive insects.
Most likely this adult has laid some eggs that will hatch next year and help control aphid and other plant-destructive insect populations.
Q: Can you tell me what is wrong with my sunflower and squash leaves? They seem to have a grayish discoloration. I also bought what I thought was a kobold blue liatris, but it looks like a garden weed. Is this what it should look like? (Moorhead, Minn.)
A: Both plants have a bad case of downy mildew, and the weed is giant foxtail. Spray plants with Daconil in the spring to prevent onset of the disease, and repeat monthly. Control the weed with a preemergent herbicide.
Q: Can you tell me what is growing on my silver maple leaves? I have been told it is harmless, but I'm still not sure. (Devils Lake, N.D.)
A: You received the correct advice. It is the harmless erineum gall. These are caused by mites in early spring. They come and go; there is no need to spray.
Q: Can you tell me the best way to control weeds in my asparagus? (Fargo, N.D.)
A: The asparagus plants should now be dormant. I'd suggest cutting the ferns back to ground level and carefully spraying the weeds with Roundup.
If there is no quackgrass present, I would suggest a shallow tilling next spring before the spears emerge, then apply a herbicide like Princep 80W or Sencor 50W. Follow the label directions.
Q: Our raspberries produce in the spring and fall but never get big enough in the fall or in July to amount to much. Can you tell me what is wrong with our raspberries and whether we should dig them out? (Huron, S.D.)
A: Raspberries are either summer or autumn bearing. From what you said in your letter, it sounds as if yours do neither. Raspberries, like strawberries, are subject to virus infections, which among other problems, cause a decline in fruit quality and quantity.
My suggestion would be to get everything dug out and burned, and start over. Information about raspberry cultivars and culture is in the publication "Refreshing Raspberries for Home-Grown Goodness" (H-38).
Q: I received 150 tulip bulbs from Amsterdam this week and have no idea how to plant them. I would like to plant them in my garden as a large group and don't want to replant them every year. Can you help? (Fargo, N.D., e-mail)
A: If you can, check into our web site, http://www.ag.ndsu.nodak.edu. There you should find the guide for planting bulbs. To be on the safe side, I am sending a bulb planting guide for your reference, "Flowering Bulbs for North Dakota" (H-992). In the meantime here is what I would suggest: Excavate the area to be planted down to about 6 inches to 8 inches. Try to get the base as level as reasonably possible. Then set the bulbs into this area, spacing them about 4 inches to 6 inches apart, depending on the size of the bulbs. Try to keep the top perpendicular to the soil surface. This will make for a dramatic show next spring. Now carefully cover the bulbs, making sure you don't knock any off center, and water in completely.
Word to the wise: Squirrels love tulips! Get some repellent or some wire covering to keep the little bounders out.
Q: What is keeping my lilac bush from growing and blossoming? About five years ago, I planted a lilac bush, it was about 2 feet tall but not many branches on it. Today it is filled out and greens up nicely, is about 3 feet tall, but does not blossom. I also have a peony planted in the same area that isn't blooming. They are planted by a low-lying city-owned lot where there is usually water standing all summer. Could this be the problem? (Fargo, N.D., e-mail)
A: The lilac needs full sunlight and relatively dry soil, as does the peony. Take that away from them, and no flowers! Move them if you can first thing next spring to a sunnier, drier location.
Q: I am wondering if it is too late to seed a lawn. What happens to the seed if it would freeze? (Clarissa, Minn., e-mail)
A: You are now in what is known as the "cusp of dormant seeding." This means that for the most part, you are applying seed now that will complete germination next spring. The seed applied now goes through the pregermination process. That is, it imbibes water, oxygen, etc. and begins the slow process of germination, which in the case of bluegrass, takes three to four weeks of ideal conditions. This is not likely to happen in October.
The seed that does germinate is usually OK, provided a snow cover takes place through the worst part of the winter. The ungerminated seed takes off like a rocket in spring when the weather warms, giving the weeds a run for their money!
Q: The leaves on my phlox are turning yellow and drying up all the way to the stem. What is wrong with it, and how do I treat it? (McLaughlin, S.D.)
A: Phlox are subject to a number of what I call "high humidity" diseases—powdery and downy mildew, leaf spots and stem blights.
Control these diseases by cutting back the frosted stems this fall and removing them. As new growth emerges next spring, keep a wary eye out for any development of the mildew and dust with sulfur or other appropriate fungicide. Sometimes increasing the spacing between the plants helps cut down on the spread of the disease, along with a reduction in overhead watering.
Q: Can you please identify the enclosed weed for me? (Valley City, N.D.)
A: Your weed is prostrate knotweed, an annual that develops and thrives where the soil is compacted. Your best bet is to hit it with a broadleaf herbicide next spring as you see it coming up. Refer to the publication "Weed Control in North Dakota Turfgrasses" (H-1009).
Q: Can you tell me how to get the birds to stop eating half of the apples off of my trees? (McVille, N.D.)
A: A couple of suggestions: try "scare balloons," that are available where most garden supplies are sold or try netting the trees before the apples ripen.
Q: I am looking for information on Corylus avellana `Contorta,' sometimes called `Contorted Weeping Filbert' and `Harry Lauder's Unique Walking Stick.' The catalog that I saw it in did not have any growing zone information but did say that it was subzero hardy. I was wondering if this shrub would survive in North Dakota. (Minot, N.D., e-mail)
A: The `Contorta' is an interesting landscape specimen, and when I lived in Ohio, it was a favorite of landscape designers and architectsto work one into the setting in some way as a focal plant. Unfortunately, they are not hardy in North Dakotaat least not dependably so. This plant was discovered in England in the last century and was at first grafted onto the species rootstock which created maintenance miseries from all the suckering that took place from the roots. Nowadays, most material sold in nurseries is cloned and does not have the problem. So, if you ever move to a warmer zone, 4 or 5, look this one up, but be sure that it is a clone and not a grafted specimen.
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Source: Ron Smith (701) 231-8161 ronsmith@ndsuext.nodak.edu
Editor: Dean Hulse (701) 231-6136