NEWS for North Dakotans
Agriculture Communication, North Dakota State University
7 Morrill Hall, Fargo, ND 58105-5665
May 21, 1998
Ron Smith, Extension Horticulturist
North Dakota State University
Q: For the last two or three years, appearing in the spring, we have had large circles in the lawn (and the circles are almost perfectly round) where the grass is thick and green. Sometimes the circles are intertwined but more likely are single. This year we have nine circles and I'm really curious to know if we have an underground rodent that I should be concerned about or if it's an animal marking its territory or what. I should tell you that the only part of the circle that is nice and green is the circumference. The center is just plain grass and the diameter of the circles is usually about five feet at the minimum.
A: Your lawn problem sounds like classic Fairy Ring disease. This is caused by decaying organic matter such as dead tree stumps and roots. It is progressive, with the circles enlarging each year. The only thing you can do is mask it with fertilization and core aeration. Eventually, the fungus will outgrow itself.
Q: My forsythia just blossoms on the short bottom branches. It grows about 4 feet a year. The upper branches either leaf out or are just dry.
A: The forysthia is showing marginal hardiness for your area. The flower buds above the snowline are killed, while those below it survive. The fact that the vegetative parttree leavesget killed off indicates to me the need to replace it with a hardier cultivar. Try `Meadowlark,' an introduction from NDSU. It is the hardiest on the market.
Q: I hope you have some ideas about what I can do with a row of Golden Currant shrubs that we planted along our front yard (250 feet) three years ago.
We didn't know anything about this shrub when it was planted, but now I'm afraid it's going to be too "high maintenance" to keep looking nice.
Unfortunately, we did not have landscaping fabric put down when the shrubs were planted, and now it is impossible to keep them weed- and quack-grass-free. I weeded each plant this spring, but the quack grass is still coming. Also, there are so many small branches to weed around.
Could we spray Roundup or Spectracide around the base of these shrubs after the first killing frost this fall? Would it help much to put landscaping fabric between each shrub now? We also thought about putting tree mulch or grass clippings at the base of each shrub, in an attempt to choke out the weeds and quack grass.
Do you have any advice on when and how to trim/prune these shrubs?
We're considering replacing all these shrubs with a more manageable planting of cottoneaster, especially because of the location in our yard.
A: Bad news! Quack grass is tough to keep in check. It would likely grow through or around the landscape fabric.
If you are unhappy with your currants, get them out as soon as possible and spray the entire area with Roundup to kill off the quack. Replant this fall with the cotoneaster.
Q: I am in need of some advice on how to get rid of a flower that is spreading in my lawn. This had originally been planted in a flower bed and then removed by digging it up. But now it has reoccurred in the flower bed and also in the lawn and is continuing to spread. I have tried to kill it with Roundup but it then comes up in another area of the lawn and also continues to come up in the flower bed in other areas. It appears to be spreading by fine tubers and seed.
I have been told that it might be a purple bell flower.
A: You might try the selective herbicide known as Confront. This effectively kills most broadleaved herbaceous plants systemically. You would probably have to apply it in the spring and again in late August for effective control.
Q: Do you know where one can purchase pasque flower plants so that they can be grown in a perennial flower garden? I have never seen them in flower/vegetable catalogs such as Guerney-Jungs-Michigan Bulb Park. If you have any help or suggestions other than trying to find them in the prairie, I would appreciate it.
A: You would probably have better luck getting the pasque flower from a bulb speciality company. They are known botanically as Anemone pulsatilla. This may help you locate them better. I found some in an old Van Dyek's flower catalogcontact them at P.O. Box 430, Brightwaters, NY 11718-0430. Thanks for writing.
Q: I'm a neighbor from South Dakota and have read your article many times in the Farm Forum. I'm very interested in weed control for winter onions and asparagus patches. I would like to know what to use on these two vegies and also where you can get "Poast." I've asked about it at different places and they don't seem to know anything about it.
A: Hi neighbor! Glad to help out! Here is an abbreviated list of herbicides to use on your two crops: Devrinol, Karmex, Poast, Roundup, Sinbar, Treflan, and 2,4-D can be used on asparagus. On onions, Buctril, Dacthal, Fusilade, Goal and Roundup are cleared. Always be sure to follow label instructions in using these herbicides. As far as being able to find Poast goes, I checked with Tessman Seed here in Fargo and they do carry it. They are wholesale distributors for the Upper Great Plains region and could likely give a source for purchasing. Contact them at (701) 232-7238 and ask for Doug or Liz.
Source: Ron Smith (701) 231-8161
Editor: Barry Brissman (701) 231-7866