These pictures were taken by me at "the bowl" in the Guadalupe Mountains National Park in West Texas. Sometimes this species is described as a variety of flexilis. Sometimes it is referred to as p. strobiformis. Whatever the name, this is the southwestern white pine in Texas.
P. strobiformis not quite exactly the same thing. P. flexilis var. reflexa (P. reflexa) is common in local gardens, probably represented mostly by the 'Vanderwolf's Pyramid' cultivar. A 'Glenmore Silver' in the Seattle arboretum was 66' high last year (2006).