Late Winter Rains and Army Cutworms

Southwest Idaho's Winter of Ice Fog ended when snow fell in early February. The ridge of high pressure that had smothered us under a season-long inversion broke up. This allowed a procession of rainstorms to wash in from the Pacific.

The Treasure Valley smelled of damp, warm soil. Ranchers, farmers, and water managers cheered the promise of ample irrigation water and plentiful grass. An artist used every shade from Absinthe to Wintergreen to paint the Boise Green Belt in living, photosynthesizing color.

The rains couldn't save this year’s crop of cheatgrass in the dry areas along the Snake River south of Boise. Last fall, a prodigious storm germinated a flush of the winter annual grass, along with its annual mustard cousins. Sadly for the plants, their good luck didn't last. Happily for me, their subsequent misfortune confirmed an accusation I made 11 years earlier.

Clouds of miller moths returned from their summer in the mountains shortly after the rain storm. The moths laid eggs that hatched into army cutworms a month or so later. The larvae soon got down to business eating the tiny green cheatgrass and mustard plants.

The dry winter that followed was ideal for the cutworms, which are thought to develop fungal diseases in damp weather. But the cheatgrass and mustards struggled in the dry weather. The annual plants died from drought or were consumed by army cutworms. Perennial grasses, with their deeper roots, survived on the hills above areas where the annuals had died.

Hungry army cutworms roamed the bare areas looking for food...

...or hid under cowpies, during the day...

...where hungry centipedes stalked.

After the larvae consumed the annual plants, they went arboreal and climbed sagebrush...

...and fourwinged saltbush and kept eating.

Army cutworms also climbed the hills to munch on perennial Sandberg bluegrass, which seemed able to outgrow the larvae's feeding.

When they ran out of plants to eat, the cutworms dined on their fallen comrades.

This spring I caught army cutworms in the act of consuming cheatgrass and creating cheatgrass die-offs. Eleven years had passed since a rancher told me army cutworms were responsible for die-offs I saw near Winnemucca, NV in 2003, and an entomologist later described to me the conditions that allowed the larvae to explode.

Ranchers Helping Salmon in Idaho's Lemhi Valley

Salmon and ranchers both need water. Salmon swim up rivers and streams to spawn; ranchers irrigate hay fields to provide winter feed for their livestock. Eastern Idaho rancher Merrill Beyeler believes that these uses can coexist.

He is increasing salmon habitat in Idaho’s Lemhi Valley while improving his ranching operation.

Beyeler is working with other ranchers, The Nature Conservancy, Idaho Fish and Game, and other groups, to remove barriers to fish, reconnect tributaries to the main Lemhi River, return the river to its previous, winding channel, and increase flow at the mouth of the Lemhi. Often, these changes mean less work for him and other ranchers.

I wrote about Merrill Beyeler’s stewardship work in the current Intermountain Farm & Ranch.

Trash the Fat

I heard a splash when I tossed my filthy Tevas into the empty bathtub. I pulled back the shower curtain and saw gray Idaho silt from my sandals mixing with dishwater, spaghetti, and tomato paste. A ring of meatball grease circled the tub. The neighbors’ kitchen sink had backed up while I was in the field for a week.

Our 1940s-era apartments had nooks for phones, built-in folding ironing boards, and Murphy beds, but no garbage disposals. I was most dismayed by the food I found floating with my Tevas, but I learned recently that the meatball grease probably caused more problems for the city.

Meridian, Idaho’s Go with the Flow Tour on June 6, 2013 followed the path water takes from the city’s wells to its wastewater treatment plant.

We filled bottles at one of the wells, were subjected to wet pranks at the water tower, and drove up Meridian Road, where the city is laying new water lines while the road is being widened.

At our final stop we saw how gravity and bacteria do the heavy lifting at the treatment plant. Gravity settles out solids into sludge and various kinds of bacteria break down dissolved impurities. The city's short film about water's outbound journey from our homes premiered at the tour. You can watch it here.

We learned that the unattractive foam on wastewater is produced by a bacterium that feeds on grease.

Microthrix parvicella forms hair-like filaments less than 1/100th the width of a human hair. The bacteria produce foam that creates problem at the treatment plant and requires special techniques to control.

The City of Meridian's Trash the Fat program reduces the amount of cooking grease reaching the wastewater facility. The Environmental Division gives away plastic scrapers and lids. Just scrape grease into a can, cover with the lid, and put in the fridge. The grease will solidify when it cools. Then put the can in the trash--but keep the lid for next time.

If you’re wondering what happens to grease that gets into the sewer, find out here. Don’t watch it while you’re eating.

If I'd known then what I know now, the almost-20-year olds living next door would have received a house-warming gift of a plastic scraper and lid.