Increasingly, the other techniques are used, such that probably no one technique dominates for meteorite dating.
Rb-Sr is a good example for explaining the process, however.
After the second half-life has elapsed, yet another 50% of the remaining parent isotope will decay into daughter isotopes, and so on.
For all practical purposes, the original isotope is considered extinct after 6 half-life intervals. A small portion of a meteorite is vaporized in the device forming ions.
Trees undergo spurts in growth in the spring and summer months while becoming somewhat dormant in the fall and winter months.