Do we need an anti-Arbor Day?

We all love trees. They provide shade, they reduce erosion, they support many insects and birds and mammals. They have been the subject of poetry and art and contemplation for thousands of years. And nobody celebrates trees quite like Nebraska, for we are the Arbor Day state.

Nebraska boasts the first Arbor Day, in Nebraska City (a naturally treed area along the banks of the Missouri River). The city is now home to the Arbor Day Lodge, the Arbor Day Foundation, and plenty of spring and fall activities centered around trees. I happen to love Nebraska City and the Arbor Day Lodge (so much so that, before we were married, my wife and I would make our annual vacation to the town for a wonderful and budget friendly weekend).

However, the result of Arbor Day has been the oversimplified mentality of: "trees, good. No trees, bad." As a result of their planting as wind breaks and post-colonization fire suppression, eastern red cedars (Juniperus virginiana) have turned diverse prairies into thickets of monoculture trees. Other planted trees, such as Siberian elms and Norway Maples have escaped cultivation and have invaded into the prairies. Even our urban native meadows can get overtaken by trees.

While trees can be very good, there are plenty of benefits to areas without trees. In the absence of trees, grasses and wildflowers can support all of the animals that prefer these habitats. While I often focus on insects on this site (because they are often overlooked), it is important to note the value of open treeless spaces for birds. Many prairie birds will not breed if there are trees in the sightline, and Nebraska is important breeding grounds for many of these prairie birds. Without the hard work of landowners and conservationists, these prairies would be overtaken by trees and lose their value to prairie specialists. Indeed, the native peoples of the United States knew the value of open prairies, and they were largely responsible for burns that prevented tree encroachment for centuries.

Grasshopper sparrow singing on top of a penstemon perch. Grasshopper sparrow populations have declined dramatically in the last several decades, largely due to loss of open prairie habitat.

Upland Sandpipers are related to shore birds, but their breeding habitat is wide open treeless prairies. This individual had a nest in a section of our family ranch on the edge of the Nebraska Sandhills.

Our family has put in countless hours to clear cedar tree overgrowth from our ranch on the edge of the Nebraska Sandhills. My parents have even recruited their friends to spend vacations cutting cedars. Now, there are entire sections without a single cedar tree. The result of this effort has been an exceptional increase in prairie bird populations the last several years (anecdotally, although I wish I had more empirical data). We now see many grasshopper sparrows, lark sparrows, upland sandpipers, greater prairie chickens, and even long-billed curlews.

Eggs concealed within the prairie grasses are protected from predators. Adjacency to trees can decrease their survival.

Even in our cities, where habitat spaces are rarely large enough to support prairie specialist birds, tree removal can improve habitat. By preventing tree encroachment into small meadows, we give room for flowering forbs and grasses. These plants are critical for the life cycles of pollinators and other beneficial insects.

So while we should continue to celebrate the value of trees on Arbor Day, perhaps we need a day where we band together to remove trees from areas where they are unwanted--an anti-Arbor Day? The marketing folks might need to work on a better title for that one. Until then, thank you to everyone putting in the hard work to keep the prairies open.

Nebraska's state bird, the meadowlark, nests on the ground and prefers prairies for breeding. Tree removal opens up breeding space for these iconic birds.

Horned larks were uncommon on our family ranch. As a result of the tree removal and opening up of prairies, I see them regularly along the fence rows.

Lark sparrows are more tolerant of scattered trees than some other prairie birds, but they do seem to benefit from clearing cedars.

Dickcissels nest on the ground and have greater breeding success with fewer trees in a prairie. Tree clearing could directly benefit this species.

A single cottonwood sticking up over a largely treeless prairie. The few cedars in this photo have been removed since this photo was taken (in 2018), but we don't remove cottonwoods (they don't form monoculture here).