a) transplanted trees of any species can take several years to start growing, and the bigger they are at transplanting, the longer it seems to take. Be patient. The fact that they've survived thus far is a good sign. Also, white pines can be very slow growers in anything other than "perfect" conditions. They're adapted to survive a wide range of soils, light conditions, and microclimates. I have one at the back of my lot that is now about ten years old, and it's barely doubled in height since it was planted. Mind you, it's growing on a rock pile... :-)
b) pines like acid soil, so test the soil, and give them some acid fertiliser if needed.
HTH
How do I test the soil? I use Hollytone on other acid-loving plants. I guess I can use that on the white pines too.
With a soil test kit. They are do-it-yourself kits sold at nurseries, home centers and hardware stores. Also, most extension agents have soil test kits where you send the soil in for analysis. This is a more thorough test.
They test for N, P, K and pH. (sodium, phosphorus, potassium, and acidity)
Your local garden supply store should have soil testing kits.
Get your soil tested by the local extension. its worth the $10. Pinching new growth helps the tree out as well. Pines are slow vertical growers. Also, if you are getting pine weevils killing the main leader, use some merit. It can cause spider mites, but will help kill the weevils.
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