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Gardening Answers Knowledgebase

Plant Answer Line Question

Keywords: Insect pests--Control, Wildlife pests, Moles

I live in Seattle and have, for the first time this fall, noticed dirt mounds on my property. These mounds tend to be located near patios/driveways, and are not in the sod. They are loamy, with no apparent holes, and are about three to five inches high. I wouldn't call them conical. There are no mole tunnels, and, as far as I can see, no bugs. The mounds are bigger than the little fine-grain mounds I have noticed in years past with small black ants crawling in them. Is there someone I can ask about what is causing these mounds, and if it is something to be concerned about? Could it be ants or mice?


From your description of the dirt mounds, it sounds as though the critter in your yard may be either a mole or a gopher. The easiest way to tell the difference is by the type of mound you have. Here is information on moles and pocket gophers from Washington Department of Fish and Wildlife's Living with Wildlife website.

Below is additional information from "Of Bugs and Blights" (in Balls and Burlaps, February 1988, pp. 4 and 14):

A gopher mound fans out from a hole near one edge of the mound. This hole remains plugged while the gopher is on the runway system. The gopher mound is relatively flat compared to the mole mound. Gopher mounds vary from 1 to 3 feet in diameter...several mounds often will be found together. They are not regularly found in a line as are mole mounds. The mole mound is somewhat conical and not much over a foot in diameter. The hole is not evident when you look at the mound. Push the soil aside and you will find it under the center of the mound. Each mound is connected with the other in a line by the moles' runway system.

According to the article quoted above, moles are more likely to be found in gardens in Western Washington than are gophers. We have the journal Balls and Burlaps in the Miller Library. The article discusses the problems and benefits of moles, as well as control methods.

I also consulted the Western Garden Problem Solver (Sunset Books, 1998) to see if I could identify your mound-maker. Ground squirrels leave their burrows open, so if your mounds show no opening, you probably don't have squirrels. Mole mounds appear volcano-like, with signs of soil excavation.

Here is a link to information on ants and their nests which you might look at to see if the images resemble the mounds of soil you are seeing.

Date 2017-05-17
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Plant Answer Line Question

Keywords: Squirrels, Wildlife pests, Bulbs

I am trying to plant some bulbs but they are being disturbed and eaten by the squirrels. Do you have any tips and tricks to protect my bulbs from being snacked on?


Here is a 2009 article by Sally Ferguson in the online archive of BC Living magazine on preventing squirrel snacking:

Q. How do I keep squirrels from digging up bulbs?
A. Squirrels can be terrible pests! They won't bother daffodils and other narcissi bulbs (which taste terrible to them!), but they find tulips and crocus in particular to be worth the effort to sniff out and dig up.
The only sure-fire way to protect tulips and crocuses and other tasty bulb treats from squirrels is to lay wire mesh such as chicken wire on top of the bed. The squirrels can't dig through the mesh and the flowers will grow neatly through the holes.
Bulbs are most vulnerable in fall immediately after planting when the soil is still soft and worked up. Digging then is easy! Squirrels often "chance" upon bulbs when burying their nuts in soft ground. Or they are attracted by "planting debris" such as bits of papery bulb tunics and other bulb-scented bits from the bulb bags. Don't advertise your plantings: clean up and keep those squirrels guessing!

Here's one neat trick that garden writer Judy Glattstein has found to work: after planting new areas, lay old window screens in frames on the ground, covering the newly-worked up soil. The screen weighs enough to foil the squirrel, but allows for air circulation and rainfall. Once the ground has settled, remove the screens and store for future use.

Another remedy that some find successful is to feed the squirrels during the fall and winter. The theory is that the local squirrel population, when offered a handy plate of peanuts or other easy-to-get treats will leave your bulbs alone. At the White House, the gardeners put up six peanut-filled feeding boxes to satiate the furry denizens there -- and reduced squirrel damage on bulb beds by 95 percent! Many gardeners claim success with commercial repellents, but these are often sticky and unpleasant to deal with, or wash away in the rain.

Home remedies include sowing cayenne pepper into the soil or on the bulbs before planting and scattering moth ball flakes on the ground. You will find advocates and detractors of both methods. A favorite Dutch remedy is to interplant Fritillaria imperialis. This tall dramatic plant gives off an odor that squirrels (and deer too, reportedly) find repellent. There is a book on the subject, Outwitting Squirrels, by Bill Adler, Jr. (1988 Chicago Review Press, Chicago, IL). It's aimed at owners of bird feeders, but you may find some helpful hints.

Date 2017-05-24
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Garden Tip

Keywords: Wildlife pests, Deer

Leave it to gardeners to transform innocent seeming Bambi into a plant eating, garden destroying monster! Outwitting Deer by Bill Adler Jr. (Lyons Press, 1999)uses humor to reveal the truth about the largest pest in the garden. The long lists of plants that deer prefer and dislike (no plant is 100% deer-proof) are most helpful, along with an honest examination of the myriad of strategies and home remedies used to repel marauding deer.

Date: 2007-07-13
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May 31 2018 13:14:08