Noun
slender medium-sized two-needled pine of eastern North America; with yellow-green needles and scaly grey to red-brown fissured bark
Source: WordNetAll species of pine, including lodgepole, jack pine, scotch pine and ponderosa pine are vulnerable. Source: Internet
For example, in explaining to us the strengths and weaknesses, uses and drawbacks of a type of tree known as the jack pine, one expects Saunders to introduce us to Jack, a member of the jack pine family. Source: Internet