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Ron Smith answers reader's questions about the world of plants and animals.

By Ron Smith, Horticulturist

NDSU Extension Service

Q: What is your opinion of the larch tree? Is it a good ornamental tree? Would it do fine in sandy, loam soil? (e-mail reference)

A: This deciduous conifer is a beauty right now with nice, yellow fall color. It is underused in our region, but I don't know why. It is hardy and has few problems, at least with the few I have seen in our area. It easily transplants when it is dormant and always looks nice and fresh with new spring growth. In a nutshell, it gets high marks from me!

Q: My neighbor gave me permission to cut some dead wood out of his apple trees. While doing the cutting, I noticed a lot of small holes in the dead wood and the live main trunks. The holes run by the thousands in a consistent pattern around the main trunks. These trees are very old, but still produce. Is the insect damage enough that the trees can’t be salvaged? (e-mail reference)

A: The holes in the bark you describe are from sapsucker bird activity. They usually do this in the spring as the sap is beginning to flow. The sap attracts insects to feed upon the syrupy concoction, which makes for a good sapsucker lunch. A more randomized collection of holes would indicate that bark beetles are feeding. When sapsuckers get carried away, they can cause girdling of the branch or stem they are working on, which kills the branch. The same holds true for bark beetle or borer activity. The larvae feed in such a manner that girdles the branch and ends up killing the branch. Only an on-site visit by an arborist can determine the viability of each tree.

Q: Can you suggest any blueberry, blackberry or seedless grape varieties that will grow in our climate? Is it best to plant these fruits in the spring? (e-mail reference)

A: You almost asked a strikeout question. There are no blueberry or seedless grapes that can be grown dependably in North Dakota that I am aware of. Black Hawk is the only blackberry variety that should do OK in our climate. Your best bet is to plant in the spring.

Q: We like squash that has a dryer texture when cooked. What is the best variety to plant? (e-mail reference)

A: The acorn-type winter squash is one of the best tasting for me. You can mix it with butter or margarine, add maple syrup to it if you wish or simply enjoy it sliced as is!

Q: I pulled up about 60 tomato plants out of my garden. Should I rake up the little tomatoes? Will it cause the soil to be acidic next year or doesn’t it matter? I also will plant other seeds at the same location. (e-mail reference)

A: They will sprout and grow as weeds next year, but will not change the soil in any significant way.

Q: I was reading information on your Web site about silver maples. I live in a historic town that is full of very old, majestic silver maples lining the streets. The two that are located on the front of our property have extensive and exposed root systems that have made our front property difficult to manage. Our dog has sprained her leg on the roots and we are somewhat worried about our toddler playing on the front lawn or what used to be a lawn. We were advised to have the trees cut down, but hate to destroy them. Is it possible to use topsoil to cover the exposed roots and then seeding or using sod to cover the area? Will this harm the tree or do you have other suggestions? (Long Island, N.Y.)

A: Removing the trees should be the last option. It often is the easiest and fastest, but many people regret the results when trees of this stature and maturity are gone. Try to locate an International Society of Arboriculture certified arborist for advice. I hope you can have some of the roots surgically removed without compromising the safety of the tree. This is something that only an on-site visitation can determine. Then a light covering of soil could be applied over the area and seeded with a shade-tolerant grass species, such as strong creeping red fescue. Also, you might want to contact someone at the Extension Service office in your county to see if it has an urban forester or horticulturist who could help you make the right decision.

Q: How do you save seeds from zinnias? Can you pick the flower and let it dry in the house or do you have to let it dry down on the plant? Also, I'd like to make sweet potato seed plants from the sweet potatoes we had grown in our garden this year. Any advise on how to do this? Thank you for your time! (e-mail reference)

A: The mature flower can be picked and dried by shaking off the seeds. If they are hybrids, keep in mind that you will not get the same thing, if you get anything at all. Removing slips from the tuberous roots propagates sweet potatoes. If you are talking about sweet potato seeds, I don't know how to advise you.

Q: My wife and I have a ficus that seems to have some sort of illness. Some of the leaves are dying and falling off. The leaves start out with a small, yellowing patch at the center of the leaf. The yellowing then grows outward, turns brown and the leaf dies. This is occurring randomly on various branches throughout the tree, but more to one side of the tree than the other. The tree also has a lot of healthy, new leaf growth. I am not able to see any evidence of any pest being the issue. Thanks in advance for any help you can offer! (e-mail reference)

A: This sounds like it could be anthracnose or botrytis fungal diseases getting started. I would suggest that you contact the Texas Extension Service in your county to see if it can line you up with a plant pathologist to help you with an accurate diagnosis and possible control solution.

Q: I was searching the Web for some information on the spacing of emerald greens and found your informative list of arborvitae questions. I live in southeastern Pennsylvania and purchased a few emerald greens to create a privacy hedge. The tag on my shrubs recommends spacing between plants of 3 to 5 feet at maturity. I spoke to three local nurseries, including the one I purchased the plants from. Two of the nurseries said that a spacing of 3 to 4 feet would be adequate. The third encouraged much wider spacing because evergreens need more space to allow for enhanced air circulation, which lessens the chances of fungus or disease problems. I want to ensure the longevity of these beautiful shrubs, but am not sure what the best advice is. My second question concerns fertilization. After planting, should I fertilize with Miracle-Gro or Hollytone, or have the shrubs received adequate fertilization while in the nursery? I would like to plant the shrubs as soon as possible, so a prompt reply would be greatly appreciated. (e-mail reference)

A: If diseases are a big problem with arborvitae in your part of the state, then heed the advice of the last nursery you talked to. My parents live just north of Philadelphia. While the relative humidity and temperature are very high whenever I visit in the summer, there doesn't appear to be a big problem with evergreen diseases because their community is almost entirely covered with deciduous trees and evergreens of almost every species. They all seemed to be doing well despite the drought-type weather they suffered through this summer. I guess it is your call. Do a little survey in your neighborhood to see if the arborvitaes are thriving where they are planted with little or no evidence of disease. If so, you probably can plant them closer than recommended by the first two nurseries you contacted. Many times the disease susceptibility of plants is in the hands of the property owners because of the maintenance they give the plants. Don’t fertilize is the answer to your last question. They shouldn’t need it and your soil will have more than enough nutrient value in it for the plants to get established. It usually is overwatering and overfertilization that lead to plant material becoming prone to disease problems. Next spring, as the plants begin new growth, you could give them a shot of Miracle-Gro and let it go at that.

Q: I had a guy stop by the office with a rose question. He said the roses grow in clusters and the bush is full of roses. The bush gets tall and slender, but needs support to grow. This year he has all kinds of seeds. Can he plant the seeds? The seeds look to be inside of a seed ball. The rose bush is very hardy, so that is the reason why he wants to plant the seeds. (e-mail reference)

A: Rose seeds are contained in what are known as "hips." Remove the seeds from the hips and rinse them in a solution of pure water (bottled) and 5 percent bleach. Follow up with a rinse in pure water again, but pouring it through a strainer. Then soak the seeds in an over-the-counter solution of peroxide for 24 hours. At this time, remove any seeds that are floating because these typically are not viable. Run the seed in a blender with pure water to remove any pulp that might be remaining. Plant in pasteurized soil and place the seeds somewhere where they can be stratified for six to nine weeks at about 35 to 40 degrees. Old salad trays from fast-food eateries are ideal for this because the trays have covers that will keep the seeds moist. After that, plant the seeds in a plant tray under plant lights for them to germinate. All of this will work if the seeds were mature enough. If they are not, nothing will happen. Rose hips often are not harvested until the plant is defoliated, which is when they positively are mature enough to germinate. Don't expect overwhelming success. If it were easy, everybody would be able to do it and we'd have a world full of amateur rose hybridizers!

NDSU Agriculture Communication

Source:Ron Smith, (701) 231-8161,
Editor:Rich Mattern, (701) 231-6136,
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