Voles are like mice except they live underground. Once you know this, evidently, you have all relevant knowledge regarding voles and could probably figure out everything else on your own. To start with, this explains how they are killing our knock-out roses. They don't chew the roots, but just tunnel down amongst them to the extent the plant just dies.
Having determined you have voles - dead roses, holes in ground - the second step is to find out if the holes are still "active." You might expect that having a perfectly good tunnel, voles would stay put and continuing adding on, but this is not necessarily so; voles sometimes leave their current domiciles and start new holes elsewhere; "the knock-out roses," goes an old vole proverb, "are knock-outier on the other side of the hole." So what you do is put an apple slice on top of the hole, and cover it with an overturned plastic plant pot. The pot you cover with a rock to make sure it does not blow away. This is known in vole-extermination circles as "the apple test." When the vole leaves his little hole, he is perplexed, he is bemused. Things are not as he expected. He thought he'd find himself in the great outdoors, and instead he is inside an overturned flowerpot. But, he thinks, things are not all bad, because what have we here - a tasty apple slice! He nibbles the apple as he ponders the strange new configuration of his tunnel's exit. When you check the flowerpots later, if the apples are nibbled, you know - aha! Voles!
Step two, is killing the voles. I watched this on a You Tube video made by a man who seemed eerily enthusiastic about the process, but I have to admit it was kind of intriguing. What you do is take two ordinary mousetraps, which you secure to the ground with nails (this is to keep them from flipping up in the air when sprung and injuring rather than killing your vole) with the trigger mechanisms pointing toward the hole. One trap is on the left side and one on the right. Are you visualizing this? Now you form a sort of tunnel over these with a section of downspout that's had one side sawed off to make a sort of U-shape. This you also secure to the ground with spikes.
When the vole leaves his home this time, there is no apple slice, but nevertheless, things are not exactly as they were. Now he finds himself in a tunnel, but no matter, he is used to tunnels. Heck, he lives in tunnels. Moreover, this tunnel has two exits. Choosing one that looks convenient, he heads toward it and snap! Dead vole. Perhaps in the last nanoseconds of consciousness, the vole thinks he should have gone the other way, but he is only fooling himself. There was a trap waiting for him in that direction also.
Too bad for the vole, I guess, but he should have left my roses alone. Perhaps when I meet the vole in heaven he will be angry at the trick I played on him. But I will tell him his experience is nothing special; my life was much the same as his. Some mornings I woke up and my expected routine was altered. Sometimes in good ways, sometimes bad. Sometimes there was an unexpected apple slice. (The apple slice in this case is metaphorical; being a human, I can get an apple slice anytime I want and don't have to depend on finding one outside my hole.) Then one day, I died. Maybe as I expire I'll think about choices I made and regret some of them: I should've ordered the salad instead of the burger, I should've waited for the light to change before crossing. But it really doesn't matter. There was a trap waiting no matter which way I went.
