Tree Talk: It's raining leaves and seeds, oh my!

We've needed moisture here in the Great Plains. We've prayed and hoped for rain, and now we're getting it – in some places, more than enough. But during the last couple of weeks, what's dropping from the sky is more than rain.

At first glance, you might think the green vegetative debris in the streets is grass clippings from lawn mowers. A closer look reveals the green along the curbs is not grass, but it is leaves – leaves from green ash trees, the most abundant tree along city streets in nearly every North Dakota community. The cool, wet spring has provided perfect conditions for ash anthracnose, a fungal disease on green ash. While early defoliation is not ideal for a tree, a tree in relatively good health can sustain loss of up to 25 percent of its leaves. Leaf drop might continue until weather conditions become drier or developing leaf tissue hardens off for the summer. Fungicides will be of little help, as they work as protectants only before the disease manifests itself. Don't bother with "revenge spraying"; most ash trees will get through this with little stress on the trees. A light dressing of nitrogen fertilizer at one to two pounds per 1,000 square feet can boost trees into growing new leaves to replace those lost. Sanitation is important to keep the disease from spreading, so rake up the leaves and dispose of them to reduce the spread of fungal spores.

Next on the list of "Things Falling from the 2022 Sky" is seeds. Brown, papery, flat-round seeds from prolific elm trees. The heavy seed production might be triggered from drought stress, which we experienced in 2021, but it might also be a result of a sufficiently "wet" winter. The current moisture levels prompt the trees to produce more seeds because conditions are favorable for seedling survival. Siberian elm trees (aka "Chinese" elms) are more likely to produce a large seed crop than American elm. There is no practical way to stop the trees from producing seeds, so we trade the nuisance for valuable ecosystem services provided by mature elms: cleaner air, reduced stormwater run-off, shade, homes for wildlife, and beautification of our yards and the entire community. And yes, many of these seeds will take root and sprout, mostly in places where a tree is not desired. The best solution is to plan some quality time in the garden, flower beds or wherever else the seeds have made a home, and gently pull them from the soil.

Keep in mind as we delve into outdoor tasks: "We might think we are nurturing our garden, but of course it is our garden that is really nurturing us." -Jenny Uglow