Q: Hi Don, thought you might be interested in seeing this ash tree growing in a silo west of St. Hilaire, Minn. - Lee Johnson
A: We've all seen tourist photos staged to look as though you're holding up the Leaning Tower of Pisa with an outstretched arm, and I suppose a photo could be staged with a tree growing behind a silo to make it appear it was growing out of the silo. But when I was young I saw trees growing inside the old silo on my grandparents' farm, probably started from windblown seed from the adjacent tree belt, and I watched them get larger each year, so I can vouch for the reality of silo trees.
Thanks for a fascinating photo. Glad to see after years of growing hidden inside the silo the tree obviously found its place in the sun.
Q: I wrote you last year about our 3-year-old aspens and your advice about adding iron did wonders. This year a couple of the trees have some mottled leaves with dry patches. Is this related to the iron condition or something else? - Grant Richardson, Fargo
A: Yes, by the photo you sent it does look like the symptoms are related to iron deficiency. When the veins of leaves remain green, and the areas between veins turn yellow, iron deficiency chlorosis is commonly the cause. As the disorder progresses, leaves can develop brown, crisp areas.
Continued iron applications both on the leaves and to the soil are the best remedies. I hope the aspens will eventually work themselves out of the condition so applying iron isn't a constant necessity. Heavy clay or alkaline soils often make it difficult for trees to access soil iron. The 'chelated' iron products available from garden centers provide iron that is more easily absorbed by plants.
Q: I have two beautiful young 20-foot tall maple trees outside our condo, which provides the mowing. Although I've maintained a circle of soil around the trees, the big mowing machines have damaged the bark at the bottoms of the trees. It's not severe yet, but when I read your recent Forum article, I became more concerned. Is there any kind of restoration that can band-aid the damaged bark? - Clem Sorgaard, Fargo.
A: Unfortunately, there isn't much that can be done after bark is damaged. Often the injury begins with a little of the outer bark scarred, revealing tannish-brown material under the gray bark. If the interior white wood is visible, the damage is even more serious.
Although injuries often begin mildly, once a mower or trimmer develops the habit of nicking trees, it seems the habit continues. Trunk wounding is cumulative, and eventually the damage works its way deeper into the trunk, which can easily lead to tree decline and death. The best prevention is keeping lawngrass away from tree trunks with mulch circles 5 feet in diameter, with mulch kept five inches away from the trunk. Thanks for reminding all of us to be vigilant with our trees.
If you have a gardening or lawn care question, email Don Kinzler at ForumGrowingTogether@hotmail.com. All questions will be answered, and those with broad appeal may be published, so please include your name, city and state for appropriate advice.