Morbid Curiosity

My beloved American elm tree has Dutch elm disease. It is just a baby, but it is a clone of the big elm that grew behind the old farmhouse. Of course I am sad, but I also have a morbid curiosity about what is going to happen to this tree. Because there is so much more to the story…  (play ripple-sounding music in your head, going back in time…)

Some of you know that I spent my career with the USDA Forest Service as a forest pathologist. I spent my days (and some nights!) trying to figure out why trees were dying and teaching land managers how to keep forests healthy. One of the subject areas that I focused on was Dutch elm disease (DED) and American elms. I compiled a 28 page publication to pull together the best current recommendations about DED, “How to Identify and Manage Dutch Elm Disease”. I worked alongside the Northern Research Station scientists and a myriad of other partners to set up studies to test and develop elms that might be resistant to DED. One of the projects I worked on was capturing clones of American elms that had survived on the landscape long enough to become big old trees, even when they were surrounded by DED. We wanted to test these “survivor elms” for resistance to DED and eventually set up seed orchards of resistant elms to produce seed for reforestation. By the time I retired, I had helped acquire clones of about 30 trees each from two different populations of American elms… a northern “cold-hardy” elm population and an Upper Mississippi elm population. That work is still in progress. But again, there is more to the story… (play sciency music in your head… whatever that might sound like…)

There was a big old American elm tree that grew in the back yard behind my parent’s farmhouse (the farmhouse where Iowisota is now). The orioles nested in the droopy branches of that tree every year. The morels popped up under it occasionally. One year when I was visiting home, I saw that the leaves were wilting and yellowing and the tree didn’t look so good… it probably had Dutch elm disease. I knew it was doomed. But the next year it was still alive. Hmmm. For some reason, it had not died. When the Forest Service was looking for survivor elms, the tree I had dubbed the “Stabe elm” fit the size criteria, so we collected young shoots from this tree to propagate into a clone. A clone of the Stabe elm is in the collection that is being tested for resistance. When we were ready to build the new house, the old elm had some structural issues and was too close to our building site, so it needed to be removed. But some of its wood lives on as a wall in the new house, and its clone lives on as one of the selections to be tested for DED resistance. And one of the clonal propagates from that tree was planted in the yard of the new house. This is the young tree that has wilt symptoms now.

So my morbid curiosity kicked in when I saw the tree wilting at the end of July. I didn’t just grieve… I went out and took a closer look. I found a tiny tell-tale hole in one of the twig crotches where elm bark beetles had fed, introducing spores of the DED fungus. Hard telling how many bark beetles fed on that tree, but I know at least one did. I cut off a wilting branch and peeled back the bark, revealing the brownish discoloration of the tree reacting to infection. Now I am watching and waiting. I see some branches with symptoms progressing, but I also still see some green healthy leaves. I wonder whether the tree will recover, or whether it will die. It is a sample size of one in an uncontrolled “experiment”, so life or death won’t really tell me anything. I hope it recovers and lives. I hope it really is resistant. But even more important, I hope that several of the many elms that we cloned turn out to be resistant to DED and will become a seed orchard passing their resistance on to progeny, so that eventually there will be more big elms that persist on the landscape!

If you ever wondered what happens to old pathologists when they retire, I can tell you they never lose their morbid curiosity, and that this one is still wandering through the woods looking at sick trees and assessing what is wrong with them! But I am also enjoying all the “wild” of the woods and planning ways to share information and the resource with others. Dennis is in charge for a private family retreat this weekend, while I head up north to paddle in the Boundary Waters Canoe Area. On August 30^th, I will teach a 2-hour workshop to make-your-own stoneware charcuterie board.  On September 10^th, we will be welcoming foraging author Bo Brown to Iowisota to lead a foraging walk and a wild food feast. And I welcome others to join me every month for a “women’s walk in the woods” – I have September and October dates on the calendar. I’ll keep making nature-themed pottery for the upcoming Northeast Iowa Artist’s Studio Tour in October. Life is busy, but we can often fit in spontaneous things, like private walks and retreats; reach out to Linda at Iowisota@gmail.com if you want to schedule something.