South Fork Cottonwood Forest

The cottonwood forest along the South Fork of the Snake River is to wildlife what Everest is to mountains. But this national treasure may one day blink out because of efforts to constrain it.

A national natural wonder is beginning to yawn and stretch in our backyard, waking slowly to begin yet another season. The narrowleaf cottonwood forests along the South Fork of the Snake River are 66 miles of some of the most unique and biodiverse habitat in the West and the largest cottonwood forest in the United States.

This giant forest has been loved to death, carved up, subdivided, robbed of water, constrained and treated like an enemy of progress, yet it has survived. Conservation easements have protected many acres from further development and engaged landowners are learning how to treat the forest and associated river banks with respect.

Despite the good work that has been done to safeguard the forest home of 126 species of birds and dozens of species of mammals, the South Fork is still shackled to the wall of Palisades Dam, and that may control the fate of the cottonwood forests.

Cottonwoods are short-lived species—ancient specimens are less than two hundred years old. What sustains the forest is the perpetual establishment of new seedlings that can grow into a forest with mature trees, brand new saplings and a host of age classes in-between. To accomplish this, they produce copious amounts of tiny seeds wrapped in wispy “cotton”. The seeds float around on the breeze hoping to land in favorable ground before their life force fails them.

And that is the rub. Because of the stringent control of the river imposed by the dam, seeds rarely encounter conditions where they can take root and prosper.  Cottonwood seeds need bare mineral soil in order to germinate and thrive and bare mineral soil is a rare commodity anywhere in a post dam river. Result: the forest ages without replenishing itself.

Two things constrain the creation of bare soil in the form of new sandbars, points and islands. First, the dam captures all the sediment from up river, allowing it to settle out before water passes through the turbines. That is the raw material the river would use to create the bare earth cottonwood seeds need.

The second constraint is water volume in the river. In 1996 a study concluded that in order to have sufficient energy to move existing gravels to create bare soil and consequently establish a new cohort of cottonwood seedlings, sustained river flows of 35,000 cubic feet per second are needed once every 15 years. Ironically, this occurred the year following the study. In 1997, flows on the South Fork reached 48,000 cfs—a boon for cottonwoods and a nightmare for humans.

Since then, the closest flows have come to the magical 35,000 cfs was 2011 when flows reached about 32,000 cfs.

The Law of Unintended Consequences started working overtime when the gates to Palisades Dam first closed in November 1956. And it has put us in a quandary—floods are bad for landowners who have built within the floodplain, but essential for the long-term health of a national treasure. Can there be a win-win here or will the forest ultimately lose to progress?

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Wildlife License Plates

Great news! as of 2024, there are three NEW designs for license plates. They still are bluebird, cutthroat trout and elk, but they are beautiful.

Idaho Wildlife license plates provide essential funding that benefits the great diversity of native plants and wildlife that are not hunted, fished or trapped—over 10,000 species or 98% of Idaho’s species diversity. Game species that share the same habitats (such as elk, deer, antelope, sage-grouse, salmon, trout) also benefit from these specialty plates.

No state tax dollars are provided for wildlife diversity, conservation education and recreation programs. Neither are any revenues from the sale of hunting or fishing licenses spent on nongame species. Instead, these species depend on direct donations, federal grants, fundraising initiatives—and the Idaho Wildlife license plates.

Both my vehicles have Bluebird Plates. I prefer the bluebird because the nongame program gets 70 percent of the money from bluebird plates, but only 60 percent of the money from elk and trout plates - 10 percent of the money from elk plates supports wildlife disease monitoring and testing programs (to benefit the livestock industry) and 10 percent from cutthroat plates supports non-motorized boat access.

Incidentally, in 2014, the Idaho Legislature denied the Department of Fish and Game the ability to add new plates or even to change the name of the elk and cutthroat plates (very specific) to wildlife and fish plates, a move that would have allowed for changing images occasionally and generating more revenue. It would seem that they believe that we Idahoans don't want a well funded wildlife program.

I think it is time we let the Legislature know that Idahoan support wildlife funding and that we would like to see these generic plates come to fruition.