Q: I’m interested in your thoughts regarding porcupine damage. We live on 80 acres of wooded land in Minnesota. Porcupines like the young, healthy, straight-trunked maples and oaks, and cause severe damage as shown in the photo. We’ve counted more than a dozen trees injured within a 100-foot circle. We’re hesitant to kill the porcupines since they are surely a part of the ecosystem, but the damage is disheartening, to say the least. — Edward F.

A: The University of Minnesota reported increasing numbers of porcupine-damaged trees in 2020. The damage often starts at the top of the tree with the bark being stripped from the upper branches, progressing to the trunk. When bark is removed down to the white wood, the tree’s branches beyond that injury usually die, if the injury extends far enough around the branch or trunk.

A similar debate about affecting ecosystems occurs when beavers injure trees along the river corridor. Should humans interfere with the animals, or let nature take its course? Both sides have presented reasonable arguments. When beavers or porcupines are live-trapped and relocated, others often quickly take their place.

Repellents can provide brief benefits but aren’t a practical long-term solution. High-value trees can be protected with fencing or metal flashing, and trees in a localized wooded setting can be surrounded with a perimeter fence. Large acreages of woodland are difficult to protect.

A reader in Minnesota says porcupines have damaged more than a dozen trees within a 100-foot circle. Special to The Forum
A reader in Minnesota says porcupines have damaged more than a dozen trees within a 100-foot circle. Special to The Forum

Newsletter signup for email alerts

RELATED COLUMNS: This mystery vine should be considered toxic, assessing the risk of trees, and transplanting houseplants | A humongous mushroom, tomato start date, and a rose-eating rabbit | A Christmas cactus mystery, sauerkraut cabbage, and eggshells for plants | A peace lily problem, boulevard vs. berm, and tips for storing produce | Identifying a groundcover plant, crabapple that attracts ‘feeding frenzy’ of birds, and controlling buckthorn

Q: The skins on our potatoes were scabby this past fall. How do I prevent it from happening this next growing season? It was new, virgin soil that didn’t have a garden before. — Connie B.

A: Potato scab is a common disease caused by soil-borne bacteria, resulting in circular, raised, corky, brownish lesions on the potato skin. Although the disease makes the tubers unsightly, the scars can be peeled off along with the potato skin, and the tubers are safe to eat.

To avoid potato scab in the future, be sure to plant certified seed potato pieces. Some potato varieties are less susceptible to scab, including Norland, which is a great red-skinned potato for our region.

Scab can be diminished by keeping soil evenly moist for four to six weeks after flowers appear. Scab-causing bacteria are more prevalent where soil organic matter is high, so avoid adding fresh manure to your garden. Scab is often more prevalent on new gardens, where increased organic matter from decaying sod creates an increased presence of bacteria. If you’re able, rotate the area in which potatoes are planted.

RELATED COLUMNS: Want to garden in 2021? Plan ahead because the pandemic is still affecting supplies | New perennial flowers to consider for 2021 | What is your tree worth? | Award-winning new flowers and vegetables for 2021 | Predicting the new year's 2021 garden trends

Q: I will be looking for shrubs this spring, mainly red twig dogwood. Can you recommend a place to get them or where I would even look? I ordered some last year but were only the size of small twigs. I’m looking for some that are more established. — Robin W.

A: Red twig dogwood is a fast-growing shrub that thrives in either sun or shade. As its name implies, the branches are red-colored, which is especially attractive against a background of white winter snow, with some cultivars having even greater scarlet brilliancy. The species can reach a height of 8 feet or more, but shorter cultivars have also been introduced.

I’m a strong advocate for shopping at locally owned garden centers, because they provide material that is well-suited to individual growing regions. From personal experience, it’s even worth paying a little more, because well-adapted, well-grown stock is the best value. Trees, shrubs and perennials are long-term investments, and buying cheap, poorly grown stock can be a waste of both money and precious years of growing time.

Dogwoods are often sold in different sizes, and you can usually find potted stock that is already 2 to 3 feet in height. If you need a quantity and budget is a factor, check with garden centers that offer economical bare-root material in the spring. Your county’s soil conservation district might also sell dogwoods for windbreak plantings.

If you have a gardening or lawn care question, email Don Kinzler, NDSU Extension-Cass County, at donald.kinzler@ndsu.edu. Questions with broad appeal may be published, so please include your name, city and state for appropriate advice.