I planted two dozen tulip bulbs today. It was tough digging in the clay soil, and I don't think I got them the 8 inches deep that you need to prevent squirrels from digging them up again (apparently squirrels get tired around 6 inches or so and give up, and go look for easier prey). One year in New Jersey I planted several in the front yard, and they were so easy to dig in! I stuck my trowel down and twisted it and just rolled those bulbs down into the dark. It turned out later that I had been following a vole tunnel, though, digging into it every few inches or so.
Now picture Mr. Vole sitting, reading his paper by a glowworm lamp, when BLAM! The Mother of All Acorns lands in his dining room. Needless to say very few of those tulip bulbs ever came up.