Mound of powdery dirt

Asked September 24, 2018, 7:38 PM EDT

One of our junipers has 5 different mounds of powdery dirt at its base and farther out from trunk. The mounds vary in size, with the largest one being about 3 feet long and 2 feet wide and 8-10 inches high. Please tell me what is causing these mounds and if and how I should get rid of them. The tree looks healthy to me otherwise, and I don't want to lose it. Thank you very much for your help!

Deschutes County Oregon

1 Response

Hi there,

These look like typical pocket gopher mounds. I don't think they will damage the tree at this stage of it's life, but they might mess up your landscaping. Whether you need to get rid of them depends on your tolerance for sharing your space with native critters.

There are ecological benefits to tunneling mammals, including pocket gophers.

According to Washington Department of Fish and Wildlife, the process of building tunnels, pantries, nests, and toilets, which eventually become abandoned, provides important nutrient cycling. These processes improve soil fertility, water transport, and and aeration for plants and microbes alike. Also, pocket gophers are important prey species for many predators, including raptors, owls, and coyotes.

You can learn more about pocket gopher ecology here: https://wdfw.wa.gov/living/gophers.html

If you decide these critters are more nuisance than benefit, there are several strategies for preventing, harassing, or removing them. I recommend "Meadow Voles and Pocket Gophers: Management in Lawns, Gardens, and Cropland" You can find that publication here: http://www.cals.uidaho.edu/edComm/pdf/PNW/PNW0627.pdf

Best,