The status of Jeffrey pine has been a subject of controversy among taxonomists since its discovery by boatanist John Jeffrey in 1852. Plant taxonomists come in two groups- lumpers and splitters. For all practical purposes Pinus jeffreyi and Pinus ponderosa are the same species. For those who insist on making a distinction between the two, ponderosa has yellow-green to grey-green needles. Jeffrey has more blue-green needles. Ponderosa cones are mostly less than 4 inches long, Jeffrey cones are up to 9 inches long. Ponderosa buds have exterior resin droplets, Jeffrey do not. Ponderosa cones have prominent prickles, Jeffrey have incurved prickles.
Rick D was definitely on the right track. Using scent to distinguish species however can always get you into trouble especially if the weather is not warm and dry.
Ponderosa is one of the most widespread and important conifers in North America with a range from British Columbia to Central Mexico, California to the Rocky Mountains and the Black Hils, SD. Jeffrey's range is confined to California except for extreme southern Oregon, and extreme northern Baja del Norte.
Ponderosas can attain a height of 180 feet with a diameter of 3 to 4 feet. Jeffreys can attain a height of 100 feet and a diameter of 4 feet.
Edited by ppine (11/02/11 05:29 PM)