Crowdsource gardening

What the crap is this critter? What does it want?

Please help, Interwebz frenz — what on earth is this, and what should I do about it? (It might be a little tough to make out in the photo, but it’s mostly black with a little light brown and white speckling on the back, about a centimetre long. And yes, I Googled “apple tree” and “beetle” already, but didn’t see anything that really matched.)

I’ve had my garden out on the deck of my condo for three years now – strawberry plants, blueberry bushes, some mint, and a dwarf apple tree, and as I chronicled for CityFood at the time, I don’t mind that other children of nature come to visit me there (flip through to page 15 if you want to check the piece out.)

However, my hospitality stops at these bugs!

Some background: as mentioned above, I’ve never had any real pest problems since setting the garden up in 2008; even an aphid infestation was dealt with fairly quickly and easily. I mulched over the winter with some maple leaves, and bought some soil (from Home Depot I think?) to top the planters up. The only new plants in the garden were two yellow Kalanchoe in 4″ pots, that I put in metal planters on the railing near the apple tree.

When I went to move the apple tree a few weeks ago, in order to get it into a sunnier spot, I grabbed the planter without a second thought and put my hand right into a cluster of about eight or ten bugs. I was DISGUSTED, because they’re, um, … crunchy.

I found a few more on the trunk of the apple tree and in the dirt at the base of it, and dispatched them quickly, but none anywhere else in the garden. A few days later I found some more, took care of them too, and figured I was done with it, until I found this one in the house today. I’m not really a squeamish person, but YUCK. I really hate these bugs! Where did they come from, and why is this the first time I’ve ever seen them?

Anyone know what these are? Will they harm the apple tree, or are they beneficial? Should I go Stompy McSmasherson on them, leave them alone, or eradicate them in another way?

Any help in the comments below would be uber-helpful from this still rookie gardener.