What kind of bet?
Bonemeal is basic (not caustic) and a source of calcium. I guess enough of it could kill a plant, but not burn roots. At least, I've never burned roots with it despite overapplication at first.
Hot amendments like blood meal, manure, etc. I have burned things with.
Too much Ca in the soil/plant can cause imbalances of P, K, Boron etc. in the plant. At least that is true of grapes & tomatoes.
Fatal? Depends I guess. Never done it.
Here:
http://www.spectrumanalytic.com/support/library/ff/Ca_Basics.htm
It says:
"Toxicity
Calcium, for all practical purposes, is not considered to have a directly toxic effect on plants. Most of the problems caused by excess soil Ca are the result of secondary effects of high soil pH. Another problem from excess Ca may be the reduced uptake of other cation nutrients. Before toxic levels are approached in the plant, crops will often suffer deficiencies of other nutrients, such as phosphorus, potassium, magnesium, boron, copper, iron, or zinc."